# Group Project:  Dividing Head - Organization and Design



## Shotgun (Mar 8, 2021)

A thread discussing the actual build is included below.  This thread has been dedicated to the design and organizational phase of the project.   Read this thread to understand what we are discussing in the follow on thread here:









						Group Project: Dividing Head - The Build
					

This will be the build thread for the group built Dividing head we will all be posting notes, pics, vids? of our progress, there can also be discussion about setups or how to do some things, order of operations or anything else that comes up pertaining to making the parts. The original thread...




					www.hobby-machinist.com
				





This is a follow on thread to the one started by GunOfNavarone.  Join this thread if you would like to join in on the construction of a dividing head.

One of the HM members, Mark_f, shared the process of building his dividing head.  Please read the thread so that we're all have a basic understanding of what will be involved, what the end product will look like, and share a common nomenclature.

To begin with, I already have a 40:1 worm gear, and the material and tooling to make several more from 7071 alloy aluminum.  This piece is 1.000" inch thick, 3.185" diameter.

The worm is a piece of 1" acme rod that is 1" long.  I drilled and tapped the set I have for a 3/8 bolt, but that can be modified.  I have material for 9 more pieces.

My shaft is 1.5" CRS, 4.5" long, threaded at 8tpi.  I have the material for 2 more pieces.  Mark_f bored his out for 3C collets.  I have MT3 on my lathe and mill.  Would this feature be best left to the final owner?

I'd like to start with Mark_f's design but improve/simplify it with hindsight.  For instance:

- the trunnion cap and disk mount arm can be one piece?
- the trunnion can be shortened to eliminate the need for the base extension?
- a pin can be incorporated into the second support to allow the trunnion to be locked into multiple positions?
- the worm can be internal threaded to eliminate the need for the nut on the crank arm?


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## Shotgun (Mar 8, 2021)

I'm barely competent at it, but I can do a 3D drawing.  I have SolidWorks.  This would definitely be a job that someone who knows drafting would do a better job at, though.


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## Braeden P (Mar 8, 2021)

Shotgun said:


> I have MT3 on my lathe and mill. Would this feature be best left to the final owner?


my lathe has a 5c spindle it is a common size and I could pick it up with my "new" tenths indicator and bore it out but the ways are worn so it wont be too accurate


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## Shotgun (Mar 8, 2021)

As a starting point for discussion, I'm making an initial division of the work/parts:

1) Drawing (Ernest, but would prefer someone more qualified)
2) Worm, Gear, and Spindle Shaft (Ernest)
3) Trunnion and Bearing with End Plates
4) Base
5) Crank with Sector Arms, Index Plates
6) Chuck/Front Index/Backing Plate, Spindle Lock with Indexing Pin

Some volunteers will have material or tools on hand that would change the design or work division.  Everything is up for compromise.  But, is it looking like a 5 person group is about right?


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## Shotgun (Mar 8, 2021)

Braeden P said:


> my lathe has a 5c spindle it is a common size and I could pick it up with my "new" tenths indicator and bore it out but the ways are worn so it wont be too accurate


The shaft for 5C collets is 1.25".   With the 1.5" stock I have, that will leave a .125 wall thickness on the spindle before it starts the taper.  Even less if there is to be any clearance for the drawbar.  Once the taper and then the threads for a backing plate are added, will there be anything left?

Should the shaft nose be left as an exercise for each member to adapt to their unique situation?


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## ttabbal (Mar 8, 2021)

I don't think 5c would fit with the thread on the OD. 3c would likely be fine, or just leave it up to the members.


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## Braeden P (Mar 9, 2021)

but 3c is uncommon 5c is more common or we could ad a er ? collet chuck on it


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## Shotgun (Mar 9, 2021)

ttabbal said:


> I don't think 5c would fit with the thread on the OD. 3c would likely be fine, or just leave it up to the members.


So that begs the question of whether the spindle should be threaded at all.  If left raw, how would the front indexing plate (or, should we call it the Quick Indexing Plate) be attached?

I'm starting to think that the 1.5" CRS that I made the spindle I have from is not appropriate for this project.  While I could drill it for a roll pin to indicate the rotary position of a Quick Indexing Plate, there would be no shoulder for it to indicate against.  If I switched to a 2" round, then I could make it match the spindle on my Atlas, including the MT3 taper on the inside.  That would give me the flexibility to use all my tooling, since my mill is also MT3.  For other members, I'd leave it raw to do that part as they see fit, but there still wouldn't be room for a 5C draw bar would there?


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## Braeden P (Mar 9, 2021)

threaded would be a good idea if we have a chuck that stays with it.


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## rwm (Mar 9, 2021)

In a perfect design, the gear and the worm would be brass? Mark's base proved to be inadequate and he added a support. The base should be redesigned. Do you think a horizontal/vertical rotary table would be an easier project? 
Robert


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## ttabbal (Mar 9, 2021)

Shotgun said:


> So that begs the question of whether the spindle should be threaded at all.  If left raw, how would the front indexing plate (or, should we call it the Quick Indexing Plate) be attached?
> 
> I'm starting to think that the 1.5" CRS that I made the spindle I have from is not appropriate for this project.  While I could drill it for a roll pin to indicate the rotary position of a Quick Indexing Plate, there would be no shoulder for it to indicate against.  If I switched to a 2" round, then I could make it match the spindle on my Atlas, including the MT3 taper on the inside.  That would give me the flexibility to use all my tooling, since my mill is also MT3.  For other members, I'd leave it raw to do that part as they see fit, but there still wouldn't be room for a 5C draw bar would there?




I would thread it. Find a common thread for this size chuck. But I also wouldn't mind if the part came to me with just a mount for the indexing plate. It's not a big deal to chuck it up and make it match whatever I want it to. Swearing at the 4-jaw and blaming the indicator is part of the experience. 

The only MT3 tooling I have is for the lathe tailstock, so I'm not sure how useful it would be for me, but I know there are collets and such. If you use a 2" round, I would probably cut an R8 taper in there for the same reason you mention MT3, my mill has R8 tooling that might be useful in there. All of them would need a draw bar, so it would need some space on the other end to mount one if you want to go that way.


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## erikmannie (Mar 9, 2021)

You can add me to the list of people who will manufacture one (or two) of the parts. I just need a drawing with tolerances on it.


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## Shotgun (Mar 9, 2021)

rwm said:


> In a perfect design, the gear and the worm would be brass?


First, we'd need to define "perfect", then recognize that it is the enemy of "good enough".  
IMHO, "perfect" should include the question, "Do I have any on the shelf?"
After that, the brass/bronze does have a lower coefficient of friction, but this gear should never be used at high speed or under load.  Otherwise you're doing it in what many call "The Wrong Way".  
Brass/bronze may be stronger that some Al alloys, but what I've got is 7071.  Stronger than some steels, and again don't do it "The Wrong Way" and the materials strength will be moot.
Brass/bronze is more corrosion resistant.  If a member planning to use this on a ship, I think that would be important.  I could possibly set up an anodizing station again?
There could be another design consideration that I have not taken into account, but "What I've got" is a pretty hard hurdle to jump.



rwm said:


> Mark's base proved to be inadequate and he added a support. The base should be redesigned. Do you think a horizontal/vertical rotary table would be an easier project?
> Robert



Agreed.  The second point in my first post of this thread was a suggestion to reduce the length of the trunnion so that the base extension would not be necessary.  The 1/4" thick plate that is the second support could be bolted directly to the main plate instead.


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## Shotgun (Mar 9, 2021)

No one is volunteering to do the drawing, and people are understandably unwilling to commit to an unknown, so I'm going to start work on a drawing this evening.  It will be in SolidWorks ('cause that's what I'm used to) and serve as a starting point/discussion aid.


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## Shotgun (Mar 9, 2021)

Woohoo!  Just checked the last haul I got from my uncle's house.  He has a yard that would set all your hearts a-flutter.  Chunks of steel everywhere.  Almost all of it is exclusively A36, of course.  He was a crane operator that was a magnet for scraps.

Anyway, I've got a 3ft length of 2" round.  I'll probably need to take 1/8" off the diameter to clean it up and have it run true, but that should leave plenty for our purposes.


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## Shotgun (Mar 9, 2021)

This is as far as I got this evening.  Lot's of features of SolidWorks that I've never even looked at, so while I have prints, I haven't figured out how to add the dimensions to them.

Comments / suggestions / feature requests / snarky jabs?


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## ErichKeane (Mar 9, 2021)

Interesting so far!  You might consider making the left "L" material out of 2 flats so that it can better flat-pack in a shipping box though.  Still having a hard time envisioning how that is going to work though.


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## Shotgun (Mar 9, 2021)

I guess I wasn't as sleepy as I thought.

I see where you're going there, @ErichKeane, but I would think the stiffness would be severely compromised if both the supports were bolted on.  I have a piece of 6"x6"x3/4" angle from my uncle that is about 10" long.  He had another 20ft of the beam.  Cut it down to the size that we need, and it still fits in one of the USPS flat rate boxes.   But, weight and size was a concern I was thinking about, so how about this instead?

All screws so far are 3/4" long, 1/4-28 socket head.  I think with a 3/4" base, it might be possible to go up to 3/8" hardware.
The main base is 3/4".  It needs mounting slots. The trunnion can possibly be lowered .25 to .5 inches, for more stiffness and less weight.
The spindle has a 1.75" nose, and a 1.5" body.  It needs threading on the tail.  Not sure about the nose. And I haven't even started on the nut.
The trunnion cap and crank are 1/4".
I need to work in a spindle lock.  Can it mount directly to the trunnion?

The trunnion crank needs a pin that indicates on the auxiliary support so the head can be locked horizontal, vertical, or in between at 5 degree increments?


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## ErichKeane (Mar 9, 2021)

I guess I don't have a good idea of scale either then   As far as screw size: 1/4-20 is a bit cheaper/easier/more common typically, so it might be worth doing that.

As far as the base: What do you mean by mounting slots?  What sort of thing were you thinking?  I have a shaper that can do interesting shapes (was just watching someone do T slots!), so I could perhaps help.

I still can't envision how this works, so sorry if these are dumb questions/suggestions...


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## Shotgun (Mar 9, 2021)

Maybe this will help.  A faceplate or chuck is mounted on the big yellow knob stick up in this picture.  I added mounting slots to the bottom.





The round bar coming in from the side is a worm, driving the gear that holds the spindle (which is vertical in this shot).  The round hole in the bottom is just to remove weight.

Now, in this picture, the trunnion has been rotated so that the worm is on top, and the spindle will be horizontal.  This is the back side, and the chuck would be mounted on the far side.





Make sure you read the thread where Mark_f, the inspiration for this one, documented his build.


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## Shotgun (Mar 9, 2021)

As to weight, SolidWorks is telling me that the Main Base would weight 9.11 pounds as drawn here.


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## Ianagos (Mar 10, 2021)

Well if you guys need my help I’d like to be in on this project. 

I can do solidworks design but also have cnc machines at my disposal. I don’t really have a need for the finished product but I’d think it would be cool to do.


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## ErichKeane (Mar 11, 2021)

I just saw this on reddit: 




__
		https://www.reddit.com/r/Machinists/comments/m2nf79

Perhaps we could ask that guy for his Solidworks drawing and see if he's interested in seeing us make it


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## Shotgun (Mar 11, 2021)

I'm game, but is this design practical?  I'm looking for some seriously experienced input on this question, because:
-How does that Selector Arm work being so thin?
-Is the handle at the highest point supposed to lock the spindle by locking the worm?  How much play would that allow in the spindle?
-I'd assume that the "chuck" could be changed out for something more pratical.
-What is holding the mechanism off the base?


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## ErichKeane (Mar 11, 2021)

I'd noticed the selector arm... that was definitely something I'd probably consider redesigning.  Same with the top handle.

Presumably just subbing out the chuck for a common chuck-thread would be easy enough.

As far as 'what is holding the mechanism off the base'... I got no idea   I invited him to join this conversation, so perhaps we can get answers/help make reasonable modifications.


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## Shotgun (Mar 11, 2021)

Ianagos said:


> Well if you guys need my help I’d like to be in on this project.
> 
> I can do solidworks design but also have cnc machines at my disposal. I don’t really have a need for the finished product but I’d think it would be cool to do.



@Ianagos , I think we have a volunteer to head up the drawing.  With the CNC capability, how would you feel about making the indexing plates?

That would have to be the most tedious job to do manually.


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## Shotgun (Mar 11, 2021)

rwm said:


> In a perfect design, the gear and the worm would be brass? Mark's base proved to be inadequate and he added a support. The base should be redesigned. Do you think a horizontal/vertical rotary table would be an easier project?
> Robert


@rwm, would you like to volunteer for a part of this project?  I could get the steel for the base from my uncle, and you're close enough that we could run it down there.  He's in Greensboro.  The stuff is 6"x6"x3/4" A36.


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## Shotgun (Mar 11, 2021)

erikmannie said:


> You can add me to the list of people who will manufacture one (or two) of the parts. I just need a drawing with tolerances on it.


@erikmannie , did you read the thread on Mark_f's build?  Which part(s?) would you find yourself being partial to building?


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## erikmannie (Mar 12, 2021)

Shotgun said:


> @erikmannie , did you read the thread on Mark_f's build?  Which part(s?) would you find yourself being partial to building?



I need some time to catch up on Mark_f’s thread.

I would have chosen the spindle, but it looks like Ernest (presumably Shotgun) has already claimed this group of parts. I don’t think I could have made a gear. If needed, I am willing to knock out just a spindle; I see nothing on the spindle that worries me. Hobbing gears, not so much.

If not the spindle, hopefully something on the lathe. I have a large precision lathe, but my mill is a PM-25MV. 

I am up for anything. What group of parts is still up for grabs?

I will get caught up on the Mark_f thread in the next 24 hours or so.


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## Ianagos (Mar 12, 2021)

Shotgun said:


> @Ianagos , I think we have a volunteer to head up the drawing. With the CNC capability, how would you feel about making the indexing plates?
> 
> That would have to be the most tedious job to do manually.



That would be good. I think the lathe is only good to .0001 degree indexing is that gonna be accurate enough ?(sarcasm)

Although I may do that on the mill I’m not sure it’s really just whatever is available at the moment.

I know my lathe has the capability to hob gears aswell but I do not know how to make it do those things but if we need something like that I can try to learn.


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## Shotgun (Mar 12, 2021)

erikmannie said:


> I need some time to catch up on Mark_f’s thread.
> 
> I would have chosen the spindle, but it looks like Ernest (presumably Shotgun) has already claimed this group of parts. I don’t think I could have made a gear. If needed, I am willing to knock out just a spindle; I see nothing on the spindle that worries me. Hobbing gears, not so much.
> 
> ...



I can let you have the spindle, @erikmannie.  The stock I have to make spindles out of is marginal anyway.

Dealer's choice, but the worm gear crank, along with it's bearing,  is another part that is going to need some tight tolerance lathe work.  I've bought a 12" length of 1" acme rod a while back that I was using for the worm.  So far, I've used 1" of it to make a hob for gear making, and 1" for the worm of the gear set that I have made.  I could cut the rest to 1" sections, then drill and tap them.  Mark_f used a nut to secure the worm section, but I don't see why we couldn't just screw it onto the worm shaft directly.

So far what we have for assignments is:

1) Drawing (@Shotgun /someone is considering but not yet committed)
2) Worm, Gear (@Shotgun )
3) Spindle Shaft (@Shotgun /@erikmannie)
4) Trunnion and Bearing with End Plates
5) Base
6) Worm Crank with Sector Arms
7) Index Plates (@Ianagos)
8) Chuck/Front Index/Backing Plate, Spindle Lock with Indexing Pin


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## Shotgun (Mar 12, 2021)

A couple points of order.  

First, @GunsOfNavarone got this all started with the inspiration of YouTube stars making videos of a group project.  Would y'all be opposed to making a short video of putting your part together?  Send them all to me and I'll do my best to put them together in an interesting manner.

Second, making a bunch of tight tolerance parts then mailing them all over the country expecting them to fit is kind of risky.  How about we commit to making the first part and shipping to the draftsman?  The draftsman would be responsible for assembling the prototype parts and sending out any change orders that might be required.


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## erikmannie (Mar 12, 2021)

Shotgun said:


> A couple points of order.
> 
> First, @GunsOfNavarone got this all started with the inspiration of YouTube stars making videos of a group project.  Would y'all be opposed to making a short video of putting your part together?  Send them all to me and I'll do my best to put them together in an interesting manner.
> 
> Second, making a bunch of tight tolerance parts then mailing them all over the country expecting them to fit is kind of risky.  How about we commit to making the first part and shipping to the draftsman?  The draftsman would be responsible for assembling the prototype parts and sending out any change orders that might be required.



I can make a video. 

What would be the ideal material for the spindle shaft? Maybe I will spring for it since you were so gracious in allowing me my first choice of part to fab, and only having to fab the one part.

Just to clarify: I’m making one spindle?


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## Shotgun (Mar 12, 2021)

erikmannie said:


> I can make a video.
> 
> What would be the ideal material for the spindle shaft? Maybe I will spring for it since you were so gracious in allowing me my first choice of part to fab, and only having to fab the one part.
> 
> Just to clarify: I’m making one spindle?



I think we agreed that you'd make a part for each participant.  The number required would be based on how many people joined. So far, that would be three:

1) Drawing (@Shotgun /someone is considering but not yet committed)
2) Worm, Gear (@Shotgun )
3) Spindle Shaft (@erikmannie)
4) Trunnion and Bearing with End Plates
5) Base
6) Worm Crank with Sector Arms
7) Index Plates (@Ianagos)
8) Chuck/Front Index/Backing Plate, Spindle Lock with Indexing Pin

As for the best material to use:  Dude, you got me.  I was going to use A36, and then try my hand at case hardening.  I'm starting my electric furnace build this weekend, which tells you exactly how much experience I have at case hardening.


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## ttabbal (Mar 12, 2021)

I have some 3" round suspected 4140 that could work for the trunnion. Depends a bit on the drawing. I don't think I have a way to put the graduations on it though. I guess I could do the lines with the rotary table on the mill. Mark's bearing looks like brass, or bronze, I can get that. 

Worm crank looks interesting. I'd need to see the drawing for it, but I could do that if the 3" material doesn't work for the trunnion. 

I like the idea of us all making one part and sending them to the draftsman for testing before making a bunch of them.


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## Shotgun (Mar 12, 2021)

ttabbal said:


> I have some 3" round suspected 4140 that could work for the trunnion. Depends a bit on the drawing. I don't think I have a way to put the graduations on it though. I guess I could do the lines with the rotary table on the mill. Mark's bearing looks like brass, or bronze, I can get that.
> 
> Worm crank looks interesting. I'd need to see the drawing for it, but I could do that if the 3" material doesn't work for the trunnion.
> 
> I like the idea of us all making one part and sending them to the draftsman for testing before making a bunch of them.



The drawing I made was 3" for the trunnion.  I'm putting your name on that, unless you object.

I think the markings would work better on the end caps.  The trunnion crank side specifically, because I want to be able to put a locator pin and lock on it anyway.  I want to reserve the space on the head side of the trunnion for the spindle lock.  We can make the End Plates a separate part, since it will require some elaborate marking (yes/no/maybe?).

1) Drawing (@Shotgun /someone is considering but not yet committed)
2) Worm, Gear (@Shotgun )
3) Spindle Shaft (@erikmannie)
4) Trunnion and Bearing (@ttabbal)
5) End Plates
5) Base
6) Worm Crank with Sector Arms
7) Index Plates (@Ianagos)
8) Chuck/Front Index/Backing Plate, Spindle Lock with Indexing Pin


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## ttabbal (Mar 12, 2021)

That should work. I'll need some room for cleanup on the diameter. But it looks like it will work.


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## Flyinfool (Mar 12, 2021)

I will do the drawing and set up the needed tolerances.
Some tolerances will seem to be tighter than necessary because normally it would be made to fit the mating piece, since the mating piece will not always be available, tolerance will need to be tight enough to be sure that it will fit and function correctly.

I will need to get additional info from each person about the part they are making so that I can be sure to design within their capabilities and use material they may have on hand. There is often many different ways to design a given part to use various manufacturing capabilities.

As in the one that @Mark_f did, everything will evolve from the gears. I will have to get with @Shotgun first to get the specifics nailed down. I will closely follow the build that Mark_f did to end up with something very similar.

I can also collect all the parts for inspection, at least as good as I can measure, I can also do some of the assembly and possibly some final fitting/adjusting if needed. I can also help people find sources material and/or tooling if they need to find something.
I am still recovering from some fairly major surgery, I have not been into my shop since before Thanksgiving and am not sure when I might be physically able to spend time standing at a machine to make any complicated parts.

Yes a horizontal / vertical would be easier and more rigid than a variable. Every moveable joint you add also adds some slop, no easy way around that.


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## Shotgun (Mar 12, 2021)

1) Drawing (@Flyinfool)
2) Worm, Gear (@Shotgun )
3) Spindle Shaft (@erikmannie)
4) Trunnion and Bearing (@ttabbal)
5) End Plates
5) Base
6) Worm Crank with Sector Arms
7) Index Plates (@Ianagos)
8) Chuck/Front Index/Backing Plate, Spindle Lock with Indexing Pin

I already may a few changes to Mark's design, because hindsight is one of my super powers!  
Like, attaching the auxiliary support plate directly to the main plate.
I think the trunnion can be shortened.  Its center only needs to be slightly longer than the gear.  That will save material and shipping weight in both the trunnion and base.  
I think it would make sense to have a flat on the trunnion next to the spindle nose that the spindle lock would bolt to.  Then the trunnion crank end cap doesn't need to be such thick material, and the lock is smaller.  I drew both end caps with 1/4" material.

If anybody else sees a reason to deviate from Mark's design, now is the time to speak up, before @Flyinfool gets to far along in the drawing.


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## Flyinfool (Mar 12, 2021)

Shotgun said:


> 1) Drawing (@Flyinfool)
> 2) Worm, Gear (@Shotgun )
> 3) Spindle Shaft (@erikmannie)
> 4) Trunnion and Bearing (@ttabbal)
> ...



I have always been known as a bit of a deviant......I tend to deviate from most things....


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## Brento (Mar 12, 2021)

Id love to join but i dont have my main machines running yet. All i have is a little watchmakers lathe. Is it possible to get the plans if this works out so i could make my own at some point?


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## Flyinfool (Mar 12, 2021)

Eventually there will be small knobs and handles that need to be made.


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## Brento (Mar 12, 2021)

I dont mind trying to do them when it comes down to it i wish i have the steady rest post bc i could then make some neat handles.


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## rwm (Mar 13, 2021)

Sorry I have been away from the thread. Busy week. I am a little under confident about jumping into this. I may watch this one from the sidelines and jump in later if that is OK. Sounds like you guys are planning multiple copies?
I was thinking about the base; whomever tackles this probably needs to own a boring head to make the holes for the trunion (I do not.) I suppose this could also be done on the lathe with a big 4 jaw. Also, I don't think it would hurt rigidity to have the base as 3 pieces. (2 sides and a base) Then you could stack the two sides and cut the trunion holes with perfect alignment. That also gives you some freedom in changing the mounting points for the base to fit specific table slots. You could just re-draw one flat part. Just some thoughts.
Do we have a more current drawing? Has anyone ever taken apart a standard BS1 dividing head for ideas?
Robert

Edit: I found this


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## ErichKeane (Mar 13, 2021)

I finally got around to reading through the original thread, though the names @Shotgun is using is a little different?  Anyway, I can make the base!

1 thing I have the ability to do thanks to a large shaper (if the bottom is thick enough!) is to cut some keyways in the bottom to put in T-slots, if we think that is valuable.

I also have both a boring head AND a large lathe, so I can do the end plates, but if they are the parts I'm thinking, isn't 1 end plate currently the same part as the base?


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## Shotgun (Mar 13, 2021)

ErichKeane said:


> I finally got around to reading through the original thread, though the names @Shotgun is using is a little different?  Anyway, I can make the base!
> 
> 1 thing I have the ability to do thanks to a large shaper (if the bottom is thick enough!) is to cut some keyways in the bottom to put in T-slots, if we think that is valuable.
> 
> I also have both a boring head AND a large lathe, so I can do the end plates, but if they are the parts I'm thinking, isn't 1 end plate currently the same part as the base?



Currently, yes one end plate is part of the base.  Made from a single piece of heavy angle iron.  The material I have is 6x6 angle that is3/4" thick.  The Auxiliary Base (and, yes, I did make up some of my own names, 'cause I didn't know that the proper ones should be), the Auxiliary Base could be bolted to the outside of the Main Base when the Trunnion holes are cut.  Also, I did draw slots for clamping, but I really don't know what the range of T-slot sizes could be, so they were very much a SWAG.

@Brento Would your watchmaker's lathe (I'm sorry that I don't know what that is) handle making the Worm Crank?  If you look at post #74 of Mark_f's thread, the worm crank and indexing pin look like small detailed parts.  Much of it could also be made from aluminum stock.  Now I'm going to go research what a watchmaker's lathe looks like.

1) Drawing (@Flyinfool)
2) Worm, Gear (@Shotgun )
3) Spindle Shaft (@erikmannie)
4) Trunnion and Bearing (@ttabbal)
5) End Plates
5) Base (@ErichKeane)
6) Worm Crank with Sector Arms
7) Index Plates (@Ianagos)
8) Chuck/Front Index/Backing Plate, Spindle Lock with Indexing Pin


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## ErichKeane (Mar 13, 2021)

Shotgun said:


> Currently, yes one end plate is part of the base.  Made from a single piece of heavy angle iron.  The material I have is 6x6 angle that is3/4" thick.  The Auxiliary Base (and, yes, I did make up some of my own names, 'cause I didn't know that the proper ones should be), the Auxiliary Base could be bolted to the outside of the Main Base when the Trunnion holes are cut.  Also, I did draw slots for clamping, but I really don't know what the range of T-slot sizes could be, so they were very much a SWAG.
> 
> @Brento Would your watchmaker's lathe (I'm sorry that I don't know what that is) handle making the Worm Crank?  If you look at post #74 of Mark_f's thread, the worm crank and indexing pin look like small detailed parts.  Much of it could also be made from aluminum stock.  Now I'm going to go research what a watchmaker's lathe looks like.
> 
> ...


Ok, let me know what we want, a 6x6 3/4" angle is likely a touch on the harder side to acquire, but I can see what is available locally.  

One thing we can do with the key is to choose a 'small' size, then use offset/adjust keys (I don't know what they are called, but they are bigger on the bottom than the top).  

Alternatively, I could do a 'made to order' based on what everyone wants.


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## erikmannie (Mar 13, 2021)

How many units are we fabricating?


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## Shotgun (Mar 13, 2021)

erikmannie said:


> How many units are we fabricating?


We're up to 6 participants so far.  The goal is for everyone to end with their own dividing head.

@ErichKeane If you can't find material that will work as the base, we can swap out.  I have material to make two bases sitting on the shelf, and I can get another 15ft if I want it.  Worst case is, I could ship you the acme rod, hob and fixture I made for making gears.  I'm good either way.

What the "keys" you are referring to?


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## Flyinfool (Mar 13, 2021)

This is why I mentioned that I will need to confer with each person about the part(s) they are making so I can taylor the design and drawings to work with their material and machines as well as fit up with everyone else's parts. There are many features that can be easily changed but may also affect other parts that can be easily changed to match.

The keys are removable tabs on the bottom of the unit to bump against the slots in the table for alignment.


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## ErichKeane (Mar 13, 2021)

Shotgun said:


> We're up to 6 participants so far.  The goal is for everyone to end with their own dividing head.
> 
> @ErichKeane If you can't find material that will work as the base, we can swap out.  I have material to make two bases sitting on the shelf, and I can get another 15ft if I want it.  Worst case is, I could ship you the acme rod, hob and fixture I made for making gears.  I'm good either way.
> 
> What the "keys" you are referring to?





Flyinfool said:


> This is why I mentioned that I will need to confer with each person about the part(s) they are making so I can taylor the design and drawings to work with their material and machines as well as fit up with everyone else's parts. There are many features that can be easily changed but may also affect other parts that can be easily changed to match.
> 
> The keys are removable tabs on the bottom of the unit to bump against the slots in the table for alignment.



Yep, those are the keys I mean!  I envision cutting a square '+' into the bottom.  You can then put a key into one of the directions to center it on you T-slots, similar to the older Kurt Vises.

I definitely think a few review cycles of customizing to the group manufacturing capabilities and and material availability (plus the group's needs) is a good idea.


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## erikmannie (Mar 13, 2021)

Shotgun said:


> We're up to 6 participants so far.  The goal is for everyone to end with their own dividing head.
> 
> @ErichKeane If you can't find material that will work as the base, we can swap out.  I have material to make two bases sitting on the shelf, and I can get another 15ft if I want it.  Worst case is, I could ship you the acme rod, hob and fixture I made for making gears.  I'm good either way.
> 
> What the "keys" you are referring to?



That is really great news that I have a chance of ending up with a dividing head, as that is on my list of future purchases.

I had thought that I was going to make one shaft, and the OP (or somebody else) was going to end up with the dividing head.

I am ready to do my part! If making X number of spindles is not enough of a contribution, I am willing to take on something else.


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## Brento (Mar 13, 2021)

@Shotgun My watch makers lathe can maybe swing up to 3/4 diameter. I can not do knurls at this point but what i can do is instead make indented ribs on the handles along the length. If someone is making up prints for it the i am sure i can make them. I can not thread on this little lathe but i can use a die to make them. Just let me know as it goes worst case i can back out of doing it
	

		
			
		

		
	



This is my watchmakers lathe.


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## ttabbal (Mar 13, 2021)

Looks like we're getting close to enough people. Any idea how wide the slot in the trunnion needs to be? I'm probably going to need to order a carbide rougher.


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## Brento (Mar 13, 2021)

Brento said:


> @Shotgun My watch makers lathe can maybe swing up to 3/4 diameter. I can not do knurls at this point but what i can do is instead make indented ribs on the handles along the length. If someone is making up prints for it the i am sure i can make them. I can not thread on this little lathe but i can use a die to make them. Just let me know as it goes worst case i can back out of doing it
> 
> 
> 
> ...


Edit that i can get away with an inch in my chuck and with the swing across the carrage.


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## Shotgun (Mar 13, 2021)

ttabbal said:


> Looks like we're getting close to enough people. Any idea how wide the slot in the trunnion needs to be? I'm probably going to need to order a carbide rougher.


I laid it out to be a 1" slot for the 1" thick gear, but that is definitely overkill.  Make the gear 3/4" or even 1/2" and it is probably still overkill.  What say ye'?


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## Shotgun (Mar 13, 2021)

Brento said:


> Edit that i can get away with an inch in my chuck and with the swing across the carrage.



Then you want to put your name in for the Worm Crank and include the Indexing pin/Handle?  I could do the crank arm, since you couldn't do that on that lathe?


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## rwm (Mar 13, 2021)

The slot could be cut with a band saw and then cleaned up with an end mill like Mark did. It may actually be harder to work with a smaller slot? This project is interesting. I could jump into the worm crank and associated hardware if Brento doesn't want to tackle it on the small lathe.
Robert


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## Brento (Mar 13, 2021)

What is the worm crank so i know exactly what part it is.

Edit: feel stupid asking that lol but its just another handle on the indexing plate side?


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## ttabbal (Mar 13, 2021)

Shotgun said:


> I laid it out to be a 1" slot for the 1" thick gear, but that is definitely overkill.  Make the gear 3/4" or even 1/2" and it is probably still overkill.  What say ye'?




If you're set up for a 1" thick gear, might as well go with it. I was thinking about using the bandsaw for the bulk of the slot, I just wanted to make sure any end mills I order would fit in the slot in case it was thinner. I can't go much bigger than 1" anyway.


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## erikmannie (Mar 13, 2021)

If we are sure that this is a go, can somebody let me know (1) how much of (2) what material is needed for the spindle shafts? Medium carbon steel (such as 1045), 4140 prehard?

I have all of my weekends to work on this. All my other fun time activities will be pushed back.


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## Brento (Mar 13, 2021)

I think 4140. Im not sure about hardness though. I know when i got to make my collet chuck at some point in the summer on my southbend it was going to be 4140 annealed


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## Shotgun (Mar 13, 2021)

Brento said:


> What is the worm crank so i know exactly what part it is.
> 
> Edit: feel stupid asking that lol but its just another handle on the indexing plate side?


The worm crank would be the shaft that holds the piece of acme rod that drives the gear.  Then there is the complicated, spring loaded pin that locks the arm into the index plate holes.


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## Brento (Mar 13, 2021)

I will try to tackle it. I will of course back out if i have trouble with anything once i get a print so i dont hold you guys up.


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## Shotgun (Mar 13, 2021)

erikmannie said:


> If we are sure that this is a go, can somebody let me know (1) how much of (2) what material is needed for the spindle shafts? Medium carbon steel (such as 1045), 4140 prehard?
> 
> I have all of my weekends to work on this. All my other fun time activities will be pushed back.


Unfortunately, we won't know exact dimensions until we finish with drawings, but the spindle should be 5" or so, I would think.  3" to pass through the trunnion, 1/2" on the rear for the nut, and 1.5" for the nose?



Brento said:


> I will try to tackle it. I will of course back out if i have trouble with anything once i get a print so i dont hold you guys up.



1) Drawing (@Flyinfool)
2) Worm, Gear, Selector Crank Arm, Spindle Lock with Indexing Pin (@Shotgun ) - - 7071 aluminum
3) Spindle Shaft (@erikmannie)  - - 4140?
4) Trunnion and Bearing (@ttabbal)
5) End Plates
5) Base (@ErichKeane) - - A35?
6) Worm Crank and Selector Pin (@Bento) - - 
7) Index Plates (@Ianagos)
8) Chuck/Front Index/Backing Plate, 

Currently, each participant will be responsible for 7 copies of the part they've agreed to make.  But, we still have a couple sections that no one has signed up for.  (I just signed on to making the spindle lock.)  None of this will be final until we've finished with the drawings, of course.

At this point I have two questions:  
First, what are y'all's expectations of timeline? (weeks?  months?  sometime before Jesus comes back?)
B) What do you envision making the part you signed up for out of?  I'd like @Flyinfool to have that guidance as early as possible.


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## ttabbal (Mar 13, 2021)

I'm thinking, keep scheduling loose, but have some requirements. Maybe 3 months? One part for inspection, once we have a go, the clock starts. It is a hobby, but we all need everyone to at least make a good effort not to be too long. So 6 parts in that time frame. Doesn't sound too bad. We can all give a better estimate when we've made one of them, of course. I'm not in any great hurry, but I'd like to enjoy the final product some before I pass on.  

I'm not 100% sure of the material I have. I'm 95% sure it's 4140PH.


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## Brento (Mar 13, 2021)

I have aluminum some brass and steel. I have stainless but i do not have much time using stainless let alone on the little lathe.

Timewise? I mean if this project was still going up into the summer i can tell you i could possibly do more bc then i will have power run to my bigger machines. With just getting back into the swing of things since its been almost 2 years since ive done machining i am going to take my time as expected everyone will be. I plan to document how i do everything just so i have notes for production time. I am in no rush as i dont have a full use for the indexer yet. This project will bring me (and my wife) joy as it will save money later on as i wont need to buy one. Also will be a great project to join.


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## Flyinfool (Mar 13, 2021)

At the moment I am the hold up, it is hard for anyone to proceed until I finish the drawings and the BOM.
It is hard for me to finish the drawings until I can get on the phone with each person as I get to their part to discuss how they plan to make it, what they have to make it from so that I can design it to work with them and their shop.
The trunion and the spindle can be almost any steel other than something like soft 1018. It does not need to be hardened. Since the spindle will be blank it would be best to not be hard so that everyone can put the end they need on it.
As for starting stock dimensions it is still to early to know for sure. 

I think there are a lot more parts than most are considering, There will be a lot of little things. There will be a number of off the shelf purchased parts. Rather than have someone buy all the purchased parts it MIGHT be best for each person to source their own purchased parts. If any of the purchased parts are of a special or expensive nature and come in packs of some quantity then it may want to be included somewhere for sharing.

Just being realistic, I would expect this whole thing to take until at least late summer.


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## Brento (Mar 13, 2021)

I know i will outsource the springs. With it being my part and i seem to have a smaller role i dont mind buying the springs for each one. As things progress we can talk more.


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## ErichKeane (Mar 13, 2021)

Brento said:


> I know i will outsource the springs. With it being my part and i seem to have a smaller role i dont mind buying the springs for each one. As things progress we can talk more.


I've made springs before, it is fun!  Works best on a bigger lathe though. I DO have a bunch of piano wire for making springs, so depending on the spring-thickness, I could possibly run off a couple of those.


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## Brento (Mar 13, 2021)

I would like to make them as well!  With this project going into late summer possibly. If i have power going i can also make em on the SB


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## ttabbal (Mar 14, 2021)

I don't mind contributing to the purchase of small commercial parts as needed. Perhaps buy a pack from McMaster or similar and send extras along with the parts that I'm making.

I forgot about material for the bearing. I don't have any brass or bronze etc.. Since I would be ordering some in, let me know what works best. 

As for time, I'm open minded. I've never tried to coordinate something like this, so I'm happy to defer to others there.. 



Flyinfool said:


> Just being realistic, I would expect this whole thing to take until at least late summer.


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## Brento (Mar 14, 2021)

As things go maybe i can save up a little money and pick up one of those steady rests and i can make the one handle custom to everyone.


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## erikmannie (Mar 14, 2021)

I won’t apply any pressure to anybody else because I would not have bought a dividing head for several years.

Having said that, I will bear down on my end when the ball is in my court (Weekend Warrior style!).


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## rwm (Mar 14, 2021)

What exactly are the end caps? Trunion ends? Does the chuck back plate require a lot index holes? Is this best a CNC or manual op?
Robert


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## Shotgun (Mar 14, 2021)

rwm said:


> What exactly are the end caps? Trunion ends? Does the chuck back plate require a lot index holes? Is this best a CNC or manual op?
> Robert


You guys are great.  Got me all excited.

Yes.  The End Caps would be the pieces bolted to each end of the Trunnion to hold it in the Base.  One is just a disk, and can be marked to indicate the Trunnion angle.  The other will hold the Worm Crank and Indexing Plates.  I took to calling that side the Trunnion Crank, since it would be used to turn the Trunnion.  One of the End Caps should have a pin that indicates on holes in the Base for quick angle sets.  

The Trunnion has a shoulder on each end that fits inside the Base holes.  I drew both End Caps with 4 bolts holes to connect to the Trunnion.  But, I think it might be better to have the round End Cap only have one hole in the center.  Then the process would be to loosen that bolt, turn the Trunnion to the desired angle, then tightening the bolt to lock it in.  The Trunnion shoulder would have to be a few thousandths shorter than the base thickness for this to work.

Mark_f bolted the Spindle Lock to the Trunnion Crank End Cap.  I think it would work better to have a flat on the side of the Trunnion that the Spindle Lock would bolt to.  That eliminates a need for the clearance on the Auxiliary Base.

I think the Chuck Plate should have indexing holes for quick indexing.  And the Spindle Lock would carry the pin for those holes.  I think this would be a good CNC job, especially if you consider the markings.

@Flyinfool I'll give you a call later today.


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## Ianagos (Mar 14, 2021)

Shotgun said:


> You guys are great. Got me all excited.
> 
> Yes. The End Caps would be the pieces bolted to each end of the Trunnion to hold it in the Base. One is just a disk, and can be marked to indicate the Trunnion angle. The other will hold the Worm Crank and Indexing Plates. I took to calling that side the Trunnion Crank, since it would be used to turn the Trunnion. One of the End Caps should have a pin that indicates on holes in the Base for quick angle sets.
> 
> ...



I can do any cnc work if need be.


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## Shotgun (Mar 15, 2021)

Here's a question.  Instead of attaching the End Cap for the Trunnion on the Main Base side with bolts, wouldn't it make more sense to use a cam-lock?   I hear that tool-less setup is what all the cool kids are doing these days.


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## ErichKeane (Mar 15, 2021)

Shotgun said:


> Here's a question.  Instead of attaching the End Cap for the Trunnion on the Main Base side with bolts, wouldn't it make more sense to use a cam-lock?   I hear that tool-less setup is what all the cool kids are doing these days.


I cannot for the life of me envision what you mean here...

That said, I suspect these endcaps are going to be bolted on 1x and stay attached forever after that.  Making them separate parts is to make it easier to ship/assemble, right?  I likely will be immediately loc-titing mine unless there is a good reason not to.


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## Shotgun (Mar 15, 2021)

The Trunnion has to rotate to move the index from horizontal to vertical.  

One End Cap holds the Worm that drives the Worm Gear to rotate the Spindle.  I called that side the Trunnion Crank.  It will be bolted to the Trunnion, and loc-tite would be appropriate.

As drawn, the other end of the Trunnion has a disk bolted to it.  You can't see it in the drawing, but the Trunnion diameter is reduced as it passes through the Main Base on that side.  The length of the reduction is slightly less than the thickness of the Main Base.  The Main Base is captured between the shoulder on the Trunnion left by that reduction and the End Cap. Tightening the bolts would lock the Trunnion to the selected angle by clamping the Main Base.

I'm suggesting here that we can replace the 4 bolts with a cam-lock, so I don't have to spend 20 minutes hunting down a wrench that I just sat beside me.


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## rwm (Mar 15, 2021)

Cam lock or just an adjustable lever?





Would either provide adequate clamping force?
Robert


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## Flyinfool (Mar 17, 2021)

Making progress on the design. Still have a lot of parts to design.


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## Brento (Mar 17, 2021)

Looking good. I am getting excited!


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## Shotgun (Mar 18, 2021)

Flyinfool said:


> Making progress on the design. Still have a lot of parts to design.


If you have time, maybe you could attach the parts you consider finished/ready for review?  Anyone who gets inspired can propose suggestions earlier.

OK.  I really just wanna look at it in 3d and spin it around and stuff.  A man's gotta have a hobby, doesn't he?


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## rwm (Mar 18, 2021)

Very nice. Will the spindle lock and the bearing for the worm crank mount on the same part? Where will you flat the trunnion? Perhaps you could just continue the flat for the spindle over further towards the base.
Also, one technical question about the trunion: when you cut the slot for the gear, I would be concerned that internal stresses would cause the "arms" to bend. Should this part be stress proof steel or stress relieved in an oven before this operation?
Robert


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## Shotgun (Mar 18, 2021)

Change in plans.  It was going to cost @ErichKeane hundreds to get the material for the base, 'cause he'd have to buy 20ft of some hefty angle.  I can get it for just a drive to see my uncle. So, I'm going to take on that part, and @ErichKeane is going to take on the gear.

1) Drawing (@Flyinfool)
2) Worm, Gear (@ErichKeane) - - 
3) Spindle Shaft (@erikmannie) - - 4140?
4) Trunnion and Bearing (@ttabbal)
5) End Plates
5) Base, Selector Crank Arm, Spindle Lock with Indexing Pin (@Shotgun )  - - A35
6) Worm Crank and Selector Pin (@Bento) - -
7) Index Plates (@Ianagos)
8) Chuck/Front Index/Backing Plate,


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## erikmannie (Mar 19, 2021)

Shotgun said:


> Change in plans.  It was going to cost @ErichKeane hundreds to get the material for the base, 'cause he'd have to buy 20ft of some hefty angle.  I can get it for just a drive to see my uncle. So, I'm going to take on that part, and @ErichKeane is going to take on the gear.
> 
> 1) Drawing (@Flyinfool)
> 2) Worm, Gear (@ErichKeane) - -
> ...



I am ready to buy the material once we are sure what we want. I just need a steel type, OD, & length. I am willing to buy & machine anything.


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## rwm (Mar 19, 2021)

delete please


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## Ianagos (Mar 19, 2021)

Let me know when you have the drawing for my part of it.


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## Brento (Mar 19, 2021)

Did you need me to call someone this weekend to talk on the phone? Ill set up a time to do so.


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## Shotgun (Mar 20, 2021)

Brento said:


> Did you need me to call someone this weekend to talk on the phone? Ill set up a time to do so.


@Flyinfool is setting up calls with individuals as he gets to that part of the drawing.  Also, I had your username wrong on the "make" list.  

Speaking of which, we still have a few spots open.  If no one wants to sign up, we'll need to recruit additional members, 

1) Drawing (@Flyinfool)
2) Worm, Gear (@ErichKeane) - -
3) Spindle Shaft (@erikmannie) - - 4140?
4) Trunnion and Bearing (@ttabbal)
5) End Plates
5) Base, Selector Crank Arm, Spindle Lock with Indexing Pin (@Shotgun ) - - A35
6) Worm Crank and Selector Pin (@Brento) - -
7) Index Plates (@Ianagos)
8) Chuck/Front Index Plate/Backing Plate,

Also, BTW, number 8 there is an either or.  We never really decided what we want to do with the business end of the device.

Quote Reply


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## erikmannie (Mar 20, 2021)

My cell number is Erik at (707)293-8973. I have no cell signal M-F during my long workdays, but weekends are wide open!


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## Flyinfool (Mar 20, 2021)

As @Shotgun said I will be calling people as I need info for their part. I want to have the part pretty much designed before we talk so we can both have an idea of what is needed and then we can decide on how to accomplish it within your capabilities. I would hate to design a part for someone that they are not capable of making.

Once I have all the parts designed then I can create a complete BOM (Bill of Material) this will list right down to every last screw, spring, washer, and anything else required whether made or purchased.

I was not going to actually create the drawing until I had most or all of the design done so that I retain the freedom to change anything to help work with someones machine capabilities. Changes to their part might require changes to other parts to match. This is the first time I am designing where each part is to made in a different shop with different and sometimes limited capability. This makes it harder but it is still a blast.

I had to take a few days off due to life getting in the way. I am feeling better now and back on it.

A few have mentioned they would like to see a 3D that they can look at, I am designing this in Solidworks, Even though I have been a Mechanical Design Engineer for the last 40+ years, I am new to Solidworks, so some things may be a bit slower that if I had access to Inventor that I used for the last 20 years. So there atr 2 options for posting files, I can post the native Solidworks files (IF the file size is uploadable) or this site will also allow uploading of STEP files which should be able to opened in almost all CAD software. 

Let me know what you would like to see.
O I can just keep posting occasional screen shot pics like the last one. Be honest, How many of you clicked on that picture and tried to rotate it, and then did it more than once.......  I know I do it all the time.

OK, I'll shut up now and get back to work.....


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## Brento (Mar 20, 2021)

I wish i could take another part but i dont have the capabilities right now to do it. I will be ready to talk any time.


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## ErichKeane (Mar 20, 2021)

I don't have a good idea how to make a scroll for a scroll chuck, but a 4-jaw style for this night be a good followup project  Perhaps a sketch of what we are considering can be helpful in deciding/finding a volunteer.


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## Brento (Mar 20, 2021)

For me i am not sure what type of attachment i will be using on the business end. I have a South Bend 9A but idk what threads the spindle is. I know i plan to get some 5c collets at some point so if that was possible to set up to hold them that would be great. Or like we once talked about leaving the spindle open for the owner to change how they want? A neat concept would be if you can set up the spindle to be interchanged in a way so you can go from 5c to a lathe chuck. Although if we set the spindle up to hold a lathe chuck with threads or which ever, i can always make my own adapter to hold 5c.


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## ttabbal (Mar 20, 2021)

Maybe include a blank mounting plate for the chuck? That way people could drill it to whatever pattern they need..


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## Shotgun (Mar 20, 2021)

ttabbal said:


> Maybe include a blank mounting plate for the chuck? That way people could drill it to whatever pattern they need..


Mike_f set his up with a quick indexing plate.  Could that double as a chuck mounting plate?


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## ttabbal (Mar 20, 2021)

Shotgun said:


> Mike_f set his up with a quick indexing plate.  Could that double as a chuck mounting plate?



I would think you could drill a few holes in it and mount a chuck to it.


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## Flyinfool (Mar 20, 2021)

The indexing plate as Mark did it would not hold the weight of a chuck. It was just for indexing, he had the nose of the spindle threaded to match his lathe chuck.

BUT it _might_ be possible for me to design the indexing plate to be strong enough to mount a chuck to.


----------



## ErichKeane (Mar 20, 2021)

Flyinfool said:


> The indexing plate as Mark did it would not hold the weight of a chuck. It was just for indexing, he had the nose of the spindle threaded to match his lathe chuck.
> 
> BUT it _might_ be possible for me to design the indexing plate to be strong enough to mount a chuck to.


Isn't an indexing plate just a plate with a bunch of holes in it that a pin goes through?  I don't really see a reason that couldn't just be a blank backing plate with a bunch of extra holes in it 

If we're doing something like that, I can volunteer for it.  Largeish rounds are cheap enough to buy, and my lathe takes material quickly, so getting them to shape isn't a problem.

The indexing holes are of course a pain, but the DRO + a stubby length drill (Removes the need for a center drill) could likely get me done with not much time investment.


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## Flyinfool (Mar 20, 2021)

The indexing plate is not normally mounted securely enough to support the weight and cutting loads of a chuck, it is just for locating the index points. But that does not mean that it could not be designed to carry those loads in this case.

I can do anything, the impossible just takes more time.


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## Brento (Mar 20, 2021)

I personally am more direct into everyone making their own backplate for the specified part and leave the indexing plates normal like the B and S style


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## Flyinfool (Mar 20, 2021)

OK, Here is the first STP file.
Remember, DO NOT start making any parts or acquiring any material based on this file, there are parts floating in air and things that WILL be getting changed.


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## rwm (Mar 21, 2021)

Impressive. 
Robert


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## Flyinfool (Mar 22, 2021)

A lot fewer parts floating in air.
Still DO NOT try to order material or make parts from these files.
I added a pic for those that do not have a CAD program to open the STEP file.

If you do see anything that may cause you issues with the parts you are making let me know so that I can work with you on it so that everyone will, or at least can be successful.


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## rwm (Mar 23, 2021)

What did you decide about the worm ratio? I confess I don't understand how to choose this. I see rotary tables using a 90:1 worm which is 4 deg per turn. That makes no sense to me? With a 72:1 worm you would have 5 deg per rotation which seems more useful. What am I missing about the 90:1 that would make it desirable?
Robert


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## DavidR8 (Mar 23, 2021)

Brento said:


> For me i am not sure what type of attachment i will be using on the business end. I have a South Bend 9A but idk what threads the spindle is. I know i plan to get some 5c collets at some point so if that was possible to set up to hold them that would be great. Or like we once talked about leaving the spindle open for the owner to change how they want? A neat concept would be if you can set up the spindle to be interchanged in a way so you can go from 5c to a lathe chuck. Although if we set the spindle up to hold a lathe chuck with threads or which ever, i can always make my own adapter to hold 5c.



Your 9A spindle has 1.5X8 TPI threads. 


Sent from my iPhone using Tapatalk


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## Shotgun (Mar 23, 2021)

rwm said:


> What did you decide about the worm ratio? I confess I don't understand how to choose this. I see rotary tables using a 90:1 worm which is 4 deg per turn. That makes no sense to me? With a 72:1 worm you would have 5 deg per rotation which seems more useful. What am I missing about the 90:1 that would make it desirable?
> Robert



We're using 40:1.  Nine degrees per turn.  The worm is going to be a short piece of acme threaded rod, which results in an approximately 3" gear.


----------



## rwm (Mar 23, 2021)

Shotgun said:


> We're using 40:1.  Nine degrees per turn.  The worm is going to be a short piece of acme threaded rod, which results in an approximately 3" gear.


Won't 9 deg per turn be cumbersome? For commonly used positioning like hexagons or octagons you will have non-integer handle rotations. I have a 4" rotab that is 72:1. I am not trying to sound critical, I just want to understand this better especially before I buy a 6" table. I guess for gear making with a dividing head you might not care about the integer synchronization? That is what the index plate is for?
Thanks
Robert


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## ttabbal (Mar 23, 2021)

It would divide evenly, which seems like about all that matters. From there you can calculate out all the hole locations for the dividing plates easily. For low count dividing like hex, you would generally use the quick dividing plate, not the worm. So long as the pin and plate have a snug fit, any error would be minimized. 

I could be missing something, as I don't do much dividing, but it doesn't seem unreasonable.


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## Shotgun (Mar 23, 2021)

My understanding is that 40:1 is the standard ratio typically used in dividing heads.  That is why I picked that particular size.  

The indexing plate is used for quick indexing when perfect accuracy isn't necessary, like for most hexa and octa gons.  A backing plate with degree marking would be sufficient.


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## Flyinfool (Mar 23, 2021)

A rotary table is a lot bigger than a dividing head, there is just not room for a bigger gear ratio. For a dividing head the ratio does not mater since it is the indexing plates doing the work. This 40 : 1 will easily do hex and oct and most other increments. The increments that are bigger prime numbers are the hard ones as each one will need a index plate for that specific division count. This happens regardless of the gear ratio.

In this case 40:1 just happens to work out with sizes that work well with the rest of the head. This is why earlier I kept saying I need the gear info as the first piece to get me started on the design.

On a rotary table the 4° per handle turn works out well with the size of the graduations and the vernier on the dial. 5° might be a little tight to get good readings. A bigger table could go with a bigger gear and maybe only 3° per turn. It just has to be a size that comes out to a whole number of degrees.


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## Shotgun (Mar 24, 2021)

@Flyinfool, Can we drop the height of the Trunnion about 1"?  Short and squat would be more rigid and lighter.  It looks like the nut end of the Spindle and the Indexing Plates would still have plenty of clearance.


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## Flyinfool (Mar 24, 2021)

Just looking at the moment it looks like it could drop about a half inch. till the spindle hits the base or about 3/4 till the indexing plate drops below t bottom of the base.
I don't yet know how much room I will need for the ideas I have for the speed indexing plate.

Once I get all the parts laid out then I can start optimizing the size and footprint


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## Flyinfool (Mar 25, 2021)

Even though it looks like a dividing head already there is still a lot of parts yet to do.

I have started on the BOM and it has 35 different parts so far, 30 of which are parts WE make, and it is not done.

There is a fair number of small fairly easy to do parts. There is something for EVERY skill and equipment level.


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## erikmannie (Mar 25, 2021)

It is still the case that I stand ready to order material and begin work on spindles.


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## Brento (Mar 25, 2021)

I am getting excited. All of this warm weather is getting my itch going on the garage. Sad part is the damn weather can change in a blink of an eye so its hard to justify pulling my garage apart to paint.


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## Flyinfool (Mar 25, 2021)

I think most of us are ready to go with making stuff, but must be patient.


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## Brento (Mar 25, 2021)

Yea i am going to be patient on making the parts too. I want to have them be best quality i can do


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## Flyinfool (Mar 25, 2021)

Another update.
I added the trunion locking and indexing features.

There are still a couple of areas that are just not right and I am still figuring out the best way to handle it


Welllllllll
It seems the step file has gotten to big for me to upload to this site. It is up to 15meg


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## ttabbal (Mar 25, 2021)

It's looking good! You could share it on Google drive, or one of the many free services out there. For now I'm happy with the images, but the full CAD will be great when I'm getting ready to machine parts.


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## Flyinfool (Mar 25, 2021)

Here is an attempt at file sharing.




__





						DividingHead.STEP
					






					drive.google.com


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## Flyinfool (Mar 25, 2021)

ttabbal said:


> It's looking good! You could share it on Google drive, or one of the many free services out there. For now I'm happy with the images, but the full CAD will be great when I'm getting ready to machine parts.


There are some including me that see a pic of a CAD screen and start trying to click on it to zoom and rotate and look at the internals but of course that don't work, BUT we still keep trying.....


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## Shotgun (Mar 26, 2021)

Do we need the extra parts for the trunnion lock?  Wouldn't clamping the Base between the Trunnion shoulder and the End Cap be enough?

I figured on keeping a T-handle hex wrench handy that would fit all the screws, and putting a cam-lock at the center of the End Cap.  The procedure would be to turn the Trunnion to where I wanted it to be, and squeeze the cam-lock to hold it in place.  Then, crank down on the four End Cap bolts to lock it solid.  It would work the same without the cam-lock, but there would be more chances to upset the setup between setting the Trunnion angle and getting the clamping screws tightened.

Manufacturing it this way would require either a low precision relief on the Trunnion side of the End Cap, or keeping the Trunnion shoulder just slightly shorter than the thickness of the base. It would eliminate three parts.

I do prefer a toolless design, but if we standardize on one size of hex head socket screw, then we can eliminate several of the t-handles.  But, some thought would need to go into where to store the wrench.


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## Shotgun (Mar 26, 2021)

Is there a reason to use countersunk vs button head screws?  I'm looking at the End Caps vs the Auxiliary Base.  Is it just a preference, or is it that the countersunk holds parts better at the expense of more precise machining?

I'm looking at this from an airplane builder's mantra of, "Simplicate and add lightness."


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## Flyinfool (Mar 26, 2021)

Yes we could make a lot less parts and give up the tool less operation. I have not looked into if all of the screws that need adjustment could use the same size wrench. I do not think it is necessary for assembly screws to use the same tool since you only do that once or for periodic maintenance.
I was trying to follow the too less operation like Mark_f did.

The only reason I changed those to flat head was to have a flat surface for the lock. Flat heads do locate things better than other screws due to the taper, in this case precise location is not needed. The 2 screws on the lock are the same as the screw for the worm gear lock.

The graduations for the angle on the trunion is not necessarily needed. There are indexing holes every 15 degrees and for other angles could rely on the user being able to measure the angle.  If you need a precise angle you would have to measure anyhow and not rely on eyeballing those graduations.

Since I posted that model I have figured out one of the areas that was bothering me. The whole mounting for the worm now works correctly.


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## Shotgun (Mar 26, 2021)

Flyinfool said:


> Yes we could make a lot less parts and give up the tool less operation. I have not looked into if all of the screws that need adjustment could use the same size wrench. I do not think it is necessary for assembly screws to use the same tool since you only do that once or for periodic maintenance.
> I was trying to follow the too less operation like Mark_f did.


How about a compromise?  Let the End Cap serve as the clamp, but use one of your t-handles in the center for locking?

I don't mind a tool so much, as  long as:

A) It is ONE tool
B) There is a secure place on the tool to store it when not in use.

A hole drilled in the base with a spring inserted would serve as a convenient and secure storage.


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## erikmannie (Mar 26, 2021)

I am okay if the design is toolless or otherwise.


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## Brento (Mar 26, 2021)

Yea same here i figure as long as it is simple to put together and work with im fine with anything.


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## Shotgun (Mar 26, 2021)

@Flyinfool , I'll leave it up to you, but if we can make all the screws the same size hex head, I will commit to machining a storage solution into the base.  It will involve drilling two holes, and using the spring from the apex seal of a rotary engine. 

Yes.  I have the parts on hand. (I just rebuilt a the rotary engine on the Dyke Delta I built.)
No. I don't think I could ever explain what the solution looks like in text.

But, I will try.

Drill a hole into a side of the base a few inches deep that is 1/8" or so larger in diameter than the hex.  Then drill a 1/8" hole at 90 degress into the first hole.  The bow shaped spring then slides into the first hole, until the trailing edge fo the spring falls into the second hole.  At this point, the spring is trapped.  Now, you can push the hex wrench in, and the spring will hold it.

The actual hex wrenches can be had for $1.50, but I'd also commit to making them from some hex rod, because. . . .reasons.


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## Flyinfool (Mar 27, 2021)

Got some pics of the spring?

SOme of this is small details that can go one way or the other. I am concentrating more on the big parts and then let the little stuff fall where it may. I work on the small easy stuff when I should be doing something but my brain is not up for critical thinking. I am averaging 4-5 hours a day 7 days a week on this project.


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## Brento (Mar 27, 2021)

With all of the assembly parts are we going to need more people? Or is each individual going to have a packet of parts to make? I am fine with a packet of parts to make. I am just curious after you saying how many parts were on the BOM.


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## Flyinfool (Mar 27, 2021)

It kind of depends on the parts, Some parts a super small and easy so it would make sense to have a group of a bunch of small easy parts, There are a couple of parts that are going to be complicated and time consuming to make along with possibly need custom fixtures needed to hold the parts for machining. Those parts it would be logical to be just the one part for a person. There may even be a part or 2 that will need work done in collaboration of 2 people to be able to accomplish everything needed. At this point it is hard to  figure the breakdown until we know the full scope of things to do. 

There are some parts that but be out of steel, Nothing at this point requires a specific grade of steel so can be made out of whatever a person has on hand or can aquire or just likes to work with. other parts can be made from Aluminum or almost any metal. And some parts can be made from almost any metal but need to be a bit stronger than AL. There may even be a couple of parts that can be made from metal or plastic and may even be candidates for 3D printing. There should be something for everyone's skill and capabilities in this project. Three are a few parts that will require very tight tolerances on some features. some will be ±.001 or even tighter if the person feels they can hold it.


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## Brento (Mar 28, 2021)

Im looking forward to my parts. I hope there are some good pieces to work on in the handles.


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## Shotgun (Mar 28, 2021)

Flyinfool said:


> Got some pics of the spring?
> 
> SOme of this is small details that can go one way or the other. I am concentrating more on the big parts and then let the little stuff fall where it may. I work on the small easy stuff when I should be doing something but my brain is not up for critical thinking. I am averaging 4-5 hours a day 7 days a week on this project.











						Mazda Rotary Engine 3MM 13-B 13B Apex Seal Spring Set   | eBay
					

Here you will be getting 1 new set of 3MM Apex Seal Springs for you r Mazda 13B engine. All engines 1986 To 2002 were 2MM Apex Seals From Mazda so in less your Engine rotors have been milled to take the 3MM stuff these will not work for you.



					www.ebay.com
				




Can you see how you could have a hole that is oversized for the hex, and then another cross-drilled to that one.  Slide the spring in, and it will get caught in the cross drilled hole.


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## DavidR8 (Mar 29, 2021)

I've been watching this thread but not participating as shipping parts to/from Canada would be stupid expensive.
But while looking for something else I ran across this:








						Versatile Dividing Head - 3 Piece Casting Set
					

To the best of our knowledge, the castings for this kit are not available elsewhere at this time. Complete instructions are in George Thomas' "Workshop Techniques" which is available at a discount when buying the castings from us - or if you built the Universal Pillar Tool you probably have the...



					www.martinmodel.com


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## ErichKeane (Mar 29, 2021)

DavidR8 said:


> I've been watching this thread but not participating as shipping parts to/from Canada would be stupid expensive.
> But while looking for something else I ran across this:
> 
> 
> ...


That guy is only a bit down the road from me   I thought about making his hand-shaper and a few of his other things a couple of times.


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## DavidR8 (Mar 29, 2021)

ErichKeane said:


> That guy is only a bit down the road from me   I thought about making his hand-shaper and a few of his other things a couple of times.


I wish he had a 5" vise casting.


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## Flyinfool (Mar 30, 2021)

Ok a question.
I am working on the indexing plate for the spindle.
What are the preferences for index spacing.
I can go as low as every 5°, but that will really be a pain to make with 72 precision slots and a lot of engraving and or stamping.
I could go every 10°, this cuts it down to 36 indexes and if someone really wanted 5° they could add another slot every other position, You would have an indexer to do this.
The other option is every 15° this would match the 15° indexing of the trunion and still hit all the common positions.

Lets discuss this so I know what you like best. Majority of responders wins. Design wise it does not make me much difference, It is just a number typed on the screen. The person making it and I together will cast the tie breaker. Capabilities can/may trump desires.
I am designing so that both index devices use the same cutting tool that is readily available.


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## ErichKeane (Mar 30, 2021)

It doesn't really matter to me, presumably I could re-make the plates any time I wanted something more.  We are doing 40-1, right?  So each full rotation represents 9 degrees.

72 holes means we can index to the .125 of a degree.
36 holes is 1/4 of a degree.
15 degrees is 24 holes, which means .375 of a degree.  The problem here is that we couldn't get even-degrees.

36 seems like a nice sweet spot, that if I had to have a preference I would be fine with.

However, if we're leaning toward 15 degrees, I'd likely prefer every 20 degrees (18 holes), as that at least gets us every 1/2 degree.


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## Brento (Mar 30, 2021)

I think a 1/2 degree is fine with me. I wouldnt need anything crazier. I doubt i would need anything more accurate.


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## rwm (Mar 31, 2021)

My understanding is that the index plate for the spindle does not involve the worm? It is for direct indexing?
I do not envy the person who will do the engraving and stamping...
R


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## Shotgun (Mar 31, 2021)

@Ianagos signed up for making the indexing plates, because he has the CNC, but I'm pretty sure that @Flyinfool is talking about the quick indexer/backing plate.

@Ianagos, would you be able to volunteer to make the Quick Index Plate with positions every 5 degrees?  I'd be happy if this part was not marked, or just "sparsely" marked (every 30 degrees?) Marking every 5 degrees would be really busy.


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## Flyinfool (Mar 31, 2021)

You are misunderstanding me.
I am not talking about the index plates that you use while making gears and such that feed thru the worm. I am talking about the quick index plate mounted to the spindle nose its self for quick common spacing's. 
The plates for actual use of uncommon spacing that feed thru the worm will cover most counts up to 100 positions.

This is the index plate I am referring to shown with 72 positions.


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## ttabbal (Mar 31, 2021)

Quick indexing is usually limited. IMO, it stops being "quick" if you have loads of positions. 72 seems like overkill. I would think you would usually use 4, 6, 8, 12, 16 maybe. After that it seems like you start getting into areas where you need to precision of the worm and plates. 

I could be wrong, I don't own one, so feel free to correct me.  

The CAD model is looking good! Thanks for all the work you're putting into it.


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## Shotgun (Mar 31, 2021)

I like your thinking, @ttabbal.  Being off by 0.1 degree doesn't mean much over 60, when you're just trying to cut a hex head on a bolt.  But, it is a big error if you're trying to hit every 1 degree to make a gear.

It is a bit late to throw this idea out, but if we had chosen 30 or 60 teeth for the worm gear, then we could have made the quick indexer with just a ping between the gear teeth.


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## Flyinfool (Mar 31, 2021)

The more I work on this the more I think 72 at 5° intervals is to much. 10° or 15° sounds better and will be less of a pain for whomever is making it. I am leaning to 15° so that 45° will be one of them. This will allow quick hex or octagons.

This is what it would look like at 15° and 24 index points.
I like this much better.


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## Flyinfool (Mar 31, 2021)

It is to late to easily go to a 30:1, that would almost be starting over with a clean sheet of paper. BUT From a distance it looks like it might be possible to go to a 60:1. that would make the gear just under 5 inch Dia, and stretch the length of the bottom of the base and the trunion by about an inch. I think there is room to do that. The problem with 60:1 is that you are getting closer to the ratios of a rotary table where when you are indexing there will be MANY turns of the crank plus some number of holes on the indexing plate. leading to the possibility of counting the turns wrong, and just a lot of cranking in general. 

Yes I am a cranky old man.....

I think we are good at our 40:1.

This quick index is easy to remove when not needed, just 2 set screws.


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## Shotgun (Mar 31, 2021)

Flyinfool said:


> This is what it would look like at 15° and 24 index points.
> I like this much better.


Me, too.

Except that no matter how hard I tried, I couldn't get the model to spin.

I'd like to see what you have in mind for the Quick Indexing Pin.  I envisioned nothing more than a pin through the locking plate.  That's all my Atlas has.


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## Shotgun (Mar 31, 2021)

Looking at the model you sent a few days back:  The graduations for the Trunnion angle disappear into the slot at about 70 degrees.  That was without the Quick Index Plate installed.  With it installed, could we roll those graduations toward the zero and put a pointer on the inside of the Main Base?


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## Flyinfool (Mar 31, 2021)

Shotgun said:


> Looking at the model you sent a few days back:  The graduations for the Trunnion angle disappear into the slot at about 70 degrees.  That was without the Quick Index Plate installed.  With it installed, could we roll those graduations toward the zero and put a pointer on the inside of the Main Base?



This could be possible. It will just get a little more tricky for whomever will be engraving it.

I am working on the pin and mounting now, I am planning to use the same pin and system as the trunion lock.

Once I get this part done I will post another model that you CAN rotate without breaking your finger or mouse.


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## Ianagos (Mar 31, 2021)

Shotgun said:


> @Ianagos signed up for making the indexing plates, because he has the CNC, but I'm pretty sure that @Flyinfool is talking about the quick indexer/backing plate.
> 
> @Ianagos, would you be able to volunteer to make the Quick Index Plate with positions every 5 degrees? I'd be happy if this part was not marked, or just "sparsely" marked (every 30 degrees?) Marking every 5 degrees would be really busy.




I’m not 100% on using the machine yet but I have a Mazak Integrex Mill turn center. Look it up but basically it’s a lathe that can do 5 axis milling.

I’m lacking in offline programming skills still. but a lot can be done in the conversational control mazatrol.






These bolts were made in one setup on that machine.


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## Flyinfool (Mar 31, 2021)

Here are some new pics to play with.


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## erikmannie (Mar 31, 2021)

I will abstain on the “number of degree” question. I will happily go along with what the rest of the group decides.

I was unable to download the STEP file on my phone. I will try a computer this weekend.

Are we at the point where I can order material for the spindles?


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## Brento (Mar 31, 2021)

I dont think so. He will tell ya when we can start ordering. I believe he wanted to talk to all of us first.


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## Shotgun (Apr 1, 2021)

Ianagos said:


> I’m not 100% on using the machine yet but I have a Mazak Integrex Mill turn center. Look it up but basically it’s a lathe that can do 5 axis milling.


That looks like one schweet machine!!


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## Shotgun (Apr 1, 2021)

@Flyinfool , is there a scheme to the color choices?  Or is it just random to help distinguish one part from another?


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## Flyinfool (Apr 1, 2021)

@lanagos That Mazak looks like fun. 

@Brento I will be contacting each person so I can understand your shop and personal capabilities to be sure I do not design a part you can not make. There are often many ways to design the same part to accommodate different manufacture processes.

@Shotgun  No scheme other than to tell the parts from each other. My boss used to pick on me and refer to my stuff as Easter eggs. But in the end he did have to agree that it was a lot easier to understand than having everything the same color. Some parts I have colored as brass just because Mark_f used brass. Some parts could be made out of almost any type of metal and some out of metal or even plastic. Others must be a specific material to be able to do their job. I am trying to keep everything as easy as possible and still have a quality useful tool at the end.


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## Flyinfool (Apr 1, 2021)

@erikmannie The STEP file is up over 18 Meg now. Getting into the range where some may have difficulty working with it. So far my laptop is hanging in there, but it is starting sweat a little when I have that main assembly open along with a few other parts that I am working on. The original SW files are a lot smaller than the STEP files but still sneaking up on my RAM limits.


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## Shotgun (Apr 1, 2021)

Are you using cosmetic threads on the bolt holes, or building them as a feature?

I see you changed up the countersunk screws to cap heads, and then there are still the button head screws on the base.  You can get back a little memory and performance by making those all the same part.  Right?

There are a couple holes in the Main Base that can go away, due to your change up.

Other than that, this drawing is getting pert near complete, if my eyes aren't deceiving me.  What's left, other than the clamp screw for the spindle lock? (and is that upside down?  It should be clamped from the other way?)


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## Doug Gray (Apr 1, 2021)

Nice job on the model Flyin!


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## Flyinfool (Apr 1, 2021)

There are a lot of little details yet to be done.
There are a lot of places that could be done different to help with the file size.

I am getting closer to the point of actually starting the 2D drawings with dimensions and tolerances.

Some threads are drawn some are cosmetic. SolidWorks is a lot harder to get what you want than what I am used to. The better I am getting at Solidworks the more I remember about why the last place I worked at did not choose it for the engineering department to use.


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## extropic (Apr 1, 2021)

Flyinfool said:


> <snip





Flyinfool said:


> The better I am getting at *SolidWorks* the more I remember about why the *last place I worked at did not choose it* for the engineering department to use.



Which CAD did your employer use?


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## Brento (Apr 1, 2021)

Inventor i think he said?  I loved inventor but now i am not allowed to get it bc they made it harder to get the trial.

@Flyinfool the file size doesnt really matter. Id rather have a good functioning tool then having something done different just to make the file size smaller.


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## Flyinfool (Apr 1, 2021)

Yes inventor is what I have used on the job for the last 20 years.
20 years ago when we were shopping for CAD software, Inventor took a lot less key strokes or mouse clicks to do the same thing, now 20 years later I find this to still be true.

NOOooooo! I would never change or compromise the design in any way for file size. Just changing how things are displayed in the 3D model on screen to help file size. Like cosmetic features instead of fully formed features, like threads and knurls. You really only need the fully formed features for a fancy presentation or for something like 3D printing. But it does eat up a lot of bytes to show these things in their full detail.

The screws that I changed from button head to cap screws are the screws that will be used all the time during actual use of the tool, I left the others button head since they are just assembly screws. I am still trying to keep all of the "In Use" screws with the same hex drive. But I think it will end up being 2 hex sizes, we shall see.


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## ErichKeane (Apr 1, 2021)

I probably won't be loading the .step file anyway, just looking at the 3views


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## Brento (Apr 1, 2021)

Im just getting excited regardless


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## erikmannie (Apr 1, 2021)

Flyinfool said:


> @erikmannie The STEP file is up over 18 Meg now. Getting into the range where some may have difficulty working with it. So far my laptop is hanging in there, but it is starting sweat a little when I have that main assembly open along with a few other parts that I am working on. The original SW files are a lot smaller than the STEP files but still sneaking up on my RAM limits.



I won’t have time to use my laptop until the weekend, but I will let you know if I cannot read the file on a PC.


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## Flyinfool (Apr 1, 2021)

Has anyone else been watching the thread of the Group Bar Clamp build?








						Group Project: Small sliding bar clamp
					

This is a follow on thread to the one started by GunOfNavarone. Join this thread if you would like to join in on the construction of small sliding bar clamps. This is intended to be a project that goes fast, is pretty straigh forward, and acts as a pilot test for group projects in general.  I'm...




					www.hobby-machinist.com
				



They are just starting to get into parts distribution, We might learn from their experience.


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## Weldingrod1 (Apr 1, 2021)

We've actually got all the part-people things sorted, and a plan for shipping. All the parts go to me, and everyone chips in for returning clamps shipping. We couldn't come up with any solutions under two shipments per part/person.

I was definitely trying to help y'all by acting as a test run!

A thought on your quick index: if you have two locations for your quick pin that doubles the resolution for relatively little hassle. Most of the cheap 5C quick indexers use a vernier pattern to make 36 holes also do 360 degrees.

Sent from my SM-G892A using Tapatalk


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## Flyinfool (Apr 1, 2021)

I looked into that, but there is just not room without making the whole thing bigger.

The plan sounds like it will work.
I have been and will still be watching to see just how the plan works in reality.


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## Flyinfool (Apr 5, 2021)

OK guys, I need a final idea of what is wanted for the nose of the spindle on this thing. As of the moment it is 2.00 OD x .719 long with the index plate installed. I know some want to be able to machine for 1.5-8 spindle to match their lathe. I need to know the various options you are thinking of to be sure I leave enough material to make it possible. I need length and diameter of what I need to leave.


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## Shotgun (Apr 5, 2021)

Flyinfool said:


> OK guys, I need a final idea of what is wanted for the nose of the spindle on this thing. I know some want to be able to machine for 1.5-8 spindle to match their lathe. I need to know the various options you are thinking of to be sure I leave enough material to make it possible. I need length and diameter of what I need to leave.


I'm the one that suggested 1.5-8, and I have the MT3 reamer to finish the inside.


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## Flyinfool (Apr 5, 2021)

I forgot to mention that I currently have a .750 hole through the spindle. Also let me know if this is a good diameter for everyone.


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## ErichKeane (Apr 5, 2021)

I don't have any machine spindle that I'd want to match, I have an MT2 on my existing rotary table, and MT4 on my lathe, so I don't think that is in common with anyone else.

Do we have an audit of all the machines that the group has?  I would be fine with 1/2-8 (common in the smaller logan lathes?) assuming it helped out enough of us.


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## Flyinfool (Apr 5, 2021)

The plan was to leave enough material so that everyone can machine whatever nose they want.
That is what I am asking right now is what everyone wants the nose to be.


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## ttabbal (Apr 5, 2021)

Space for 1.5-8 with 0.75" through hole would be fine with me. It might be nice for those of us with ER40 collets if we could thread a M50-1.5 on there. That's close to 2in though, so it might be too much. I can make an adapter if I really want them that badly.  

I bet a 3jaw would live on there most of the time. My lathe is D1-4, so using the same chucks is a bit more complicated. 

I could see R8 being handy in the nose, since many are likely to have collets already. Lots of adapters available for other tapers as well. That would be easy to add if you want it though. If the plan could allow enough space in there to fit it, great, if not, there are other options.


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## Flyinfool (Apr 5, 2021)

How much length do you need for a 1.5-8 spindle nose?

M50 is a bit smaller than 2 inches so that should work. How much length is needed?

How much total spindle length do you need for an R8 and draw bar?

See the theme here, I am trying to get numbers for how big do you want it?


----------



## Brento (Apr 5, 2021)

I have a southbend so id like to have the nose with enough material for a chuck from that.


----------



## Shotgun (Apr 5, 2021)

The chuck on the Atlas needs a flange to register against on the back side, so the 2" diameter works for me.  And then I need 1" for threads.  So a 2" diameter, 1.25" long nose will work for me.


----------



## Flyinfool (Apr 5, 2021)

Brento said:


> I have a southbend so id like to have the nose with enough material for a chuck from that.



I don't have a South Bend, I need to know how much material you need in the nose.


----------



## ttabbal (Apr 5, 2021)

Flyinfool said:


> How much length do you need for a 1.5-8 spindle nose?
> 
> M50 is a bit smaller than 2 inches so that should work. How much length is needed?
> 
> ...




MOAR BIGNESS!

M50 needs about 3/4" of threads. Maybe 1" total. Probably similar for a threaded chuck. 

R8 will fit diameter wise. Total collet length is 4". Drawbar would just need enough room to draw the collet in. 1/4" is likely more than enough. 

I don't have any specific needs, just putting ideas out there that might be helpful.


----------



## Brento (Apr 5, 2021)

The lathe threads for me are 1.5 - 8. Idk how much i would need to cut that bc i cant get to the lathe at the moment to see how much material i would need


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## Flyinfool (Apr 5, 2021)

My Mill is a Z collet and my lathe is a D1-4. So my needs are probably different that anyone else. Anything other than what I have, I have no idea how big it is until someone tells me.

I have started the process of making the drawings and deciding tolerances.


----------



## Brento (Apr 5, 2021)

The other thing is if there is a more popular size that everyone else has then i can always make an adaptor if i needed like others are saying. I just havent been able to play with my lathe to know how much material would be needed. I know 2" in diameter would prob be okay for me but idk the length needed on the nose.


----------



## extropic (Apr 5, 2021)

Brento said:


> The other thing is if there is a more popular size that everyone else has then i can always make an adaptor if i needed like others are saying. I just havent been able to play with my lathe to know how much material would be needed. I know 2" in diameter would prob be okay for me but idk the length needed on the nose.


You can solve this problem.

Open a new thread in  - - -  *South Bend FORUM *- - - .  "I have a ________ (model, size) lathe with a 1.500-8 spindle thread. I don't have access to the late right now but I need to know how long the spindle snout is (including, thread, registration diameter and flange). Can someone please post a picture with a scale sitting on top of the spindle nose? Thank you."


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## Shotgun (Apr 5, 2021)

Flyinfool said:


> My Mill is a Z collet and my lathe is a D1-4. So my needs are probably different that anyone else. Anything other than what I have, I have no idea how big it is until someone tells me.
> 
> I have started the process of making the drawings and deciding tolerances.


Any chance you could share the solidworks files for me to play with?  Give everyone a chance to give last minute input before it goes to drawings?


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## Flyinfool (Apr 5, 2021)

Here are some files to play with.
There are 49 Solidworks Files involved at about 30M in size.
I still have a few small details to deal with yet.
Just because it is starting to go to paper does not mean that I can not make changes. I expect changes after I get all the drawings done and I can talk to each person about the parts they are making.


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## Brento (Apr 5, 2021)

Total length of register and threads is 7/8". Length of threads alone is 11/16". Diameter of the register is 1.509". This is for my southbend 9A nose.


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## extropic (Apr 6, 2021)

I've been following along and need to comment on a couple of design features.

I suggest adding a second worm support (reddish part) on the other side of the spindle and extending the worm shaft so that the worm is not cantilevered as currently shown. I see that such a change will cover the existing angle engraving on the trunnion, but that engraving can be relocated to radial marking on the worm support. The gear mesh will be much more durable if you support the worm from both sides.

Also, I think I see two large jam nuts on the back of the spindle. Consider the hex size and how un-common wrenches will be. Instead of buying or fabing wrenches, I suggest using a single cylindrical nut (maybe knurled OD) with some blind holes for a pin and at least one threaded setscrew. Drop in a brass ball, to protect the spindle threads, before installing the set screw(s).


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## Flyinfool (Apr 6, 2021)

I had thought about the cantilevered worm gear. Since this is a dividing head and not a rotary table, the worm should never be driving against a load, it is just doing positioning There are locks for the worm shaft and the spindle and the trunion to clamp everything solid during a cut.

Sometimes I forget that not everyone has all the same tools as I do. I have wrenches that fit those nuts, most probably don't. I am already using brass tipped setscrews for the spindle indexing plate.


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## ErichKeane (Apr 6, 2021)

Flyinfool said:


> I had thought about the cantilevered worm gear. Since this is a dividing head and not a rotary table, the worm should never be driving against a load, it is just doing positioning There are locks for the worm shaft and the spindle and the trunion to clamp everything solid during a cut.
> 
> Sometimes I forget that not everyone has all the same tools as I do. I have wrenches that fit those nuts, most probably don't. I am already using brass tipped setscrews for the spindle indexing plate.


IMO, I'd probably prefer a knurled nut to use with a pin wrench (like 5c collet blocks use).


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## Shotgun (Apr 6, 2021)

ErichKeane said:


> IMO, I'd probably prefer a knurled nut to use with a pin wrench (like 5c collet blocks use).


What's a pin wrench?


----------



## extropic (Apr 6, 2021)

Shotgun said:


> What's a pin wrench?







__





						pin wrench - Google Search
					





					www.google.com


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## ErichKeane (Apr 6, 2021)

extropic said:


> __
> 
> 
> 
> ...


Yep! This style in particular; https://www.amazon.com/GearWrench-G...t=&hvlocphy=9032901&hvtargid=pla-881141976622


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## Shotgun (Apr 6, 2021)

Gotcha.  But, if we're talking about a hex wrench of a size that people are unlikely to have, how does a $30 wrench that will have exactly one use improve the situation?

How about the inner lock nut being replaced by a bearing washer, and then the spindle being turned down so that a 1" nut could be used.  It could be an OTS nylock or a castle-nut.  Everyone has an adjustable wrench that size.  Don't they?


Right.  Because the center has to open up for collets.


----------



## Shotgun (Apr 6, 2021)

How about the slot pattern used on ER32 collet nuts?


----------



## ErichKeane (Apr 6, 2021)

Shotgun said:


> Gotcha.  But, if we're talking about a hex wrench of a size that people are unlikely to have, how does a $30 wrench that will have exactly one use improve the situation?
> 
> How about the inner lock nut being replaced by a bearing washer, and then the spindle being turned down so that a 1" nut could be used.  It could be an OTS nylock or a castle-nut.  Everyone has an adjustable wrench that size.  Don't they?
> 
> ...


Do we NOT have them? I would figure a 5c collet block set is so common that we'd all have one already.


----------



## Brento (Apr 6, 2021)

I dont have one but if i needed one for this id get one. I am still tooling up and only have 1 5c collet tool that will use the collets.


----------



## extropic (Apr 6, 2021)

My suggestion was to incorporate "some blind holes for a pin".
The nut doesn't have to be tight, like a draw nut for a 5C does.
It just sets and maintains the axial clearance or the spindle which will not require to be "tightened".
The blind holes/pin are really for some worst case scenario.
I expect that all will have (or can make) an appropriate pin (or rod, or punch).
No uncommon tools required.

Also, regarding the brass ball vs a brass tipped setscrew.
On the commercial brass tipped screws that I have seen/used, the tips are fixed (press fit or bonded) to the screw shank.
That type is not desirable for locking a thread because the rotation of the locking screw will rotate the brass element.
You don't want the brass element to rotate (wear away, create debris). You want the brass element to be non-rotating.
I recommended a brass ball because they are inexpensive and available in multiple sizes from McMaster-Carr.
The force of the setscrew will deform the ball, creating a thread-like form to bear on the spindle thread without damage.
Make sure the locking screw tip (setscrew in this case) has a relatively smooth tip to bear on the brass element.
Certainly, the brass ball could be replaced by an appropriate slug of brass rod.


----------



## Flyinfool (Apr 6, 2021)

I am close to that also, I have one 5C collet, a 3/16 and a vertical/horizontal collet closer that I bought for one specific job. I did happen to have one other use for a collet since then that just also happened to be 3/16.

You are correct, this nut does not need to any more than a very light finger tight or it will bind the spindle.
I will get back to that sometime tomorrow, I hope. Right now I am dealing with the aftermath of my 2nd covid shot.


----------



## Shotgun (Apr 6, 2021)

ErichKeane said:


> Do we NOT have them? I would figure a 5c collet block set is so common that we'd all have one already.


I don't have 5C collets.  Just ER32


----------



## extropic (Apr 7, 2021)

Flyinfool said:


> I had thought about the cantilevered worm gear. *Since this is a dividing head and not a rotary table, the worm should never be driving against a load*, it is just doing positioning There are locks for the worm shaft and the spindle and the trunion to clamp everything solid during a cut.
> 
> Sometimes I forget that not everyone has all the same tools as I do. I have wrenches that fit those nuts, most probably don't. I am already using brass tipped setscrews for the spindle indexing plate.



To emphasize and clarify my suggestion for better support the worm shaft; I think the bold statement is shortsighted.
I think the strength of the gear mesh or a torque limiter (shear pin?) should be the weak link in the gear train, not the mounting support of the worm.
I know this is not intended to be a full industrial universal dividing head, but I would want to perform some milling operations while rotating the spindle and not be concerned about the worm shaft. It looks like such an easy fix.
Universal dividing heads are designed to have the spindle driven during a milling operations for the purpose of creating features such as spirals and cam slots.
A great upgrade (outside the scope of this thread) would be to incorporate an electronic drive along the lines of the electronic leadscrews we see.

I think I've made my point, will bow out and leave it to the participants to decide.

One thing I've already learned from this thread, If I were to ever propose such a group build, I would want a completed set of drawings in hand on day one. Not necessarily set in stone (changes to be negotiated amongst the participants) but ready to go, if agreed.
That's not a criticism of this project in any way. Flyinfool is doing an excellent and critical job. The thread has run very smoothly. None the less, it's at 200+ replies and the design is still in work.

Good luck all.

Watching with interest.


----------



## Brento (Apr 7, 2021)

I am liking @extropic idea for the support. If it isnt alot to change i think it would be nice to have the support so in the future you can use the head during milling.  Up to everyone else.


----------



## Shotgun (Apr 7, 2021)

Brento said:


> I am liking @extropic idea for the support. If it isnt alot to change i think it would be nice to have the support so in the future you can use the head during milling.  Up to everyone else.



It would be some MAJOR rework. 

You'd need a support attached to the Trunnion on the opposite side.  To make space for that, you'd need to slide the Worm Gear toward the Trunnion Crank, reshape the Worm Shaft, wipe out the graduations on the Trunnion, and then add more parts for the support.  As it stands, the Worm Shaft is about as thick as it is long, and and is supported by 3/4" thick steel that has a clamping/locking feature.  The teeth on the gear/worm are about 1/8" deep and 3/4" wide.  If you're cranking on that thing hard enough to make it warp so much it skips a tooth, you're doing it wrong.  Not paying attention AND abusing the tool.

Remember:  Perfection is the enemy of good enough.

Also, we did not start this build completely blind.  We had a good write up of a working example from Mark_f, and the genesis of a SolidWorks model that @Flyinfool took up and ran with, doing the leg work of consulting with each participant to make sure they could make the parts.  If we had started with a full set of drawings, I hardly think we'd be any further along than we are now.


----------



## Shotgun (Apr 7, 2021)

Also, having built some complex contraptions that started with a set of plans, I can say that it is truly amazing how what first seems like an innocuous change usually results in a ripple of unintended modifications.


----------



## Shotgun (Apr 7, 2021)

extropic said:


> Universal dividing heads are designed to have the spindle driven during a milling operations for the purpose of creating features such as spirals and cam slots.



This statement piqued my interest, @extropic.
To make a spiral, there would have to be some sort of coordination to lock the rotation of the dividing head's spindle to the advancement of the mill table it was attached to.  

First, do I have that right?  
Does the mill table have to have some sort of power take off to drive the dividing head?  
Do these commercial dividing heads also allow the piece to be positioned at any arbitrary angle as this design allows?


----------



## Ianagos (Apr 7, 2021)

Shotgun said:


> This statement piqued my interest, @extropic.
> To make a spiral, there would have to be some sort of coordination to lock the rotation of the dividing head's spindle to the advancement of the mill table it was attached to.
> 
> First, do I have that right?
> ...



Most of the old school dividing heads I’ve seen have had the capability to do helixes if you had the gearbox. Typically that would also consist of a set of gear that mount to the x axis handwork and a 90degree gearbox of some sort. It’s a more advanced feature but a useful one. 

I don’t think we need to design it with that on mind as I’m betting way too many guys have all types of mills and hard to make it work with any kind although that could be up to them.

I have thought the unsupported worm was a bit odd. Typically I also see an eccentric bearing on the worm to it can be rotated to compensate for wear. I could also imagine this being done with a self aligning or cylindrical bearing?(not sure if that’s the correct term) on the fixed end and a bearing that rides in a slot on the tail end that can be adjusted via set screw.

Whatever the case I do think compensation for backlash should be integral in the design and I also believe to achieve a low level of backlash both ends of the screw should be supported so it cannot flex.

I need to download the solidworks model and take a look better as I’ve just looked at the pictures


----------



## rwm (Apr 7, 2021)

I know Tom Lipton has done it:




Robert


----------



## ttabbal (Apr 7, 2021)

The explanation for the worm support sounds fine to me. I see the reasons for wanting it supported on both sides, but if it's that much work to redesign the part I'm good either way. 

For the electronic stuff, we can go there. You can either go with the gear chain to drive it, or use a sensor on the table or lead screw and move the dividing head as needed with a stepper/servo. For the gears, you don't need the electronics, but it's only as flexible as the stack of gears you have. I guess the question is, do the people building this want the ability? I mean, how often do you want to mill a helix? Are the other things you can make with it that are more common? I think I'd hesitate to get too far into this part yet, as the dividing head itself is a prerequisite. And the final design matters for the drive.


----------



## Shotgun (Apr 7, 2021)

Ianagos said:


> Typically I also see an eccentric bearing on the worm to it can be rotated to compensate for wear.


The current design has that feature.  Notice the arm on the inside of the mount.  It also allow for rotating the Worm out of the way to allow for quick indexing.


----------



## Shotgun (Apr 7, 2021)

rwm said:


> I know Tom Lipton has done it:


That is one of the cooler hacks I've seen lately.

Also, way outside the scope of what I envisioned using this thing for.  You can bet I will give it a try once I have a dividing head put together, though.


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## Brento (Apr 7, 2021)

I agree with @ttabbal if it is a PITA to redesign to add the support then i am also good. Either way im farther along then before bc i dont have a dividing head period.


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## Flyinfool (Apr 7, 2021)

The eccentric on the work is not only for adjusting for wear, but it so you can disengage the worm to use the quick indexing on the spindle.

I believe I can add a second support and still keep the ability to disengage the gears. I am looking at where all the snowball will roll down this hill. Give me some time to play with this idea......


----------



## extropic (Apr 7, 2021)

Shotgun said:


> This statement piqued my interest, @extropic.
> To make a spiral, there would have to be some sort of coordination to lock the rotation of the dividing head's spindle to the advancement of the mill table it was attached to.
> 
> *First, do I have that right?
> ...



Yes, you have that correct.
The "power take off" (in pre-electronic times) was to remove the nearside handwheel and set up the drive train from the table leadscrew.
A Universal Dividing Head is capable of using indexing plates as per any Dividing Head.

I never intended to imply that either a gear drive accessory set or an electronic drive were within the scope of this existing project.
I did intend to advise participants that both are possible "next steps" for the adventurous hobbyists. A "complete" mechanical drive gear train is a massive undertaking (so are many hobbyist projects). However, it wouldn't surprise me to see a future thread describing the build of an electronic drive attachment to one of the dividing heads being built here.


----------



## Flyinfool (Apr 7, 2021)

One never knows.......
You got me thinking, and everyone knows that it is always dangerous when I start thinking......


----------



## Shotgun (Apr 7, 2021)

Flyinfool said:


> One never knows.......
> You got me thinking, and everyone knows that it is always dangerous when I start thinking......


Easy there, @Flyinfool .  Steady as she goes.


----------



## Flyinfool (Apr 7, 2021)

Shotgun said:


> Easy there, @Flyinfool .  Steady as she goes.


But, But, But, But, I am already hyperventilating...... and having thoughts.....


----------



## ErichKeane (Apr 7, 2021)

Flyinfool said:


> But, But, But, But, I am already hyperventilating...... and having thoughts.....


Slowly... Disengage brain, engage worm gear


----------



## Flyinfool (Apr 10, 2021)

OK, I'm better now.
Was a close call.
Let a lot of the magic blue smoke out from between my ears.

I looked at what it would take to add the dual support to the worm shaft. One change affects another and it is a cascading effect, It would be a pretty major redesign to add it at this point and might even eliminate some other features. Unless a majority of us would really like it, I would say we should pass on that one. The shaft as designed is pretty hefty and I think that even if you added a stepper or servo drive for spiral cuts down the road I think it would still be fine.

As for the double custom made jam nuts with 2 inh hex on the bottom of the spindle, That would be a simple change to make it something like a round nut that is knurled and locked by set screws, then no one has to come up with a special wrench or spanner to tighten it. You really will not want it any more than a light finger tight. Just enough to eliminate end play of the spindle.
Whether it is the nuts or a round, it is still parts (2 nuts or 1 round) someone has to make.

Let me know your thoughts.


----------



## Shotgun (Apr 11, 2021)

I like one round nut with a set screw.  Simple, solid, and no special tools.


----------



## Shotgun (Apr 17, 2021)

@Flyinfool, got any updates?


----------



## Flyinfool (Apr 17, 2021)

I got slowed down a bit due to going to a few job interviews. It also took me a bit to figure out how to create a drawing format and title block.

I am back to making drawings at least for the weekend, I am expecting /hoping for a couple more interviews next week.

I have made a bunch of small changes to the models, and added more hardware. I'll try to get an update posted soon.


----------



## Flyinfool (Apr 18, 2021)

Here are files to play with.


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## Shotgun (Apr 19, 2021)

This is looking beautiful.  I spent hours spinning it around (the actual model.  Not the image this time.)

I think the drawing is close enough to complete that we might want to revisit our assignment list.  When we last looked at who was doing what:


1) Drawing (@Flyinfool)
2) Worm, Gear (@ErichKeane) - -
3) Spindle Shaft (@erikmannie) - - 4140?
4) Trunnion and Bearing (@ttabbal)
5) End Plates
5) Base, Selector Crank Arm, Spindle Lock with Indexing Pin (@Shotgun ) - - A35
6) Worm Crank and Selector Pin (@Brento) - -
7) Index Plates (@Ianagos)
8) Chuck/Front Index Plate/Backing Plate,

I signed up for the Selector Crank Arm, but I don't know that it makes sense.  I have access to so much of that 3/4" structural steel for free, that I think it would make more sense for me to be responsible for the Base, Spindle Lock, and Trunnion Crank.  Basically, all the 3/4" stuff.


----------



## erikmannie (Apr 19, 2021)

I am still in for what I am signed up for. 

Do we want 4140 prehard or annealed? I can order material this Friday (4/23) if you tell me the OD and total length.


----------



## Flyinfool (Apr 19, 2021)

The Spindle can be almost any grade steel that you want to machine. It is not like anything on this will run at high speed and realistically I am sure most of us will not put a lot of hours on it.

I have a good start on the drawings, But I am deciding final clearances and tolerances as I make each mating parts drawings. Soon I will be able to post a set of preliminary drawings. There may be more changes based on the capabilities of each member of this project.


----------



## Flyinfool (Apr 19, 2021)

Are there any lurkers here that might want to join in the fun. there are plenty of parts to go around. Once we officially start making parts it will be late to jump in.

Here is the BOM so far. There is still some hardware to be added but all the parts that need someone to make are there.
I have all purchased parts listed with McMaster-Carr part numbers, they do not have to be purchased there, but it is a way to identify the parts and a possible source.


----------



## Flyinfool (Apr 19, 2021)

I added all the names to the BOM from the list above that @Shotgun posted, If I did it correctly, there are 16 parts not yet accounted for.
Here is the updated BOM with the names on it. Check it out to be sure I understand what you are each volunteering for.


----------



## ErichKeane (Apr 19, 2021)

Once the drawings are out, I might grab a few more items. Want to make sure I know what I'm volunteering for first!


----------



## Brento (Apr 19, 2021)

Ill have to see more of the certain parts. One thing i may need help on working out as of now will be the index crank nut. As thing project continues though it is getting closer to me having a mill ready.


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## Ianagos (Apr 20, 2021)

I think the spindle should be 4140 pre hard. Or something hardened. 17-4 in h900 is about 47hrc and machines great.

I have a heat treat oven if that’s necessary. I may also be sending a ton of parts out for case hardening soon aswell so I could probably sneak a few parts in with that job if need be.

I don’t want to take on too much but I also have a cylindrical grinder if we really need. But I’d rather hard turn. I feel pretty confident holding .0002” on my lathe.


----------



## Shotgun (Apr 20, 2021)

It may be a naming issue, but I'd like to be clear what I've signed up for.
The base made of 3/4" thick angle.
The auxiliary base, made of 1/4" angle and bolted to the main base.
The spindle lock, colored blue in the picture.
The trunnion crank, colored red in the picture.

You have me on the indexing crank with @Brento.  I'd like you to take that if you could, @Brento.
Could I please beg off from being responsible for the lock pins and bushings?  I think I'll be pushing myself with all these large, precision holes in thick plates.


----------



## Brento (Apr 20, 2021)

I can most likely do the crank. I think once we get drawings of each part it will be easier to see what each part everyone is making for better knowledge.


----------



## Shotgun (Apr 21, 2021)

Here's an idea.  @Flyinfool , could you update the drawing to color code the parts based on who is signed up for them?  Leaving the unassigned pieces grey.


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## Flyinfool (Apr 21, 2021)

@Shotgun,
The Aux Base is 1/4 plate, not angle.
I had you and @Brento both on the crank because it looked like you were both signed up for it. I will change it to just Brento.
I will remove you from the lock pins and bushings.

I will look into changing the colors to indicate the maker.

I will see if I can put together a PDF of the drawing package so far.


----------



## Flyinfool (Apr 21, 2021)

OK, Here are the drawings so far. These are NOT finished drawings. Do NOT try to make parts from them. Critical dimensions are still being adjusted and missing info has yet to be added. These are for reference only. There are some parts of the project that I have plans for changes to.


----------



## ErichKeane (Apr 21, 2021)

BTW: Would be awesome if when you're done-er that you order those/mark those as who is signed up for them.  Would make it easier to decide what additional things I can take on.  

I see one of the 'end plates' that would be easy enough to make (and I could likely knock them out quickly enough), so I might grab that too, but I want to see all the drawings first


----------



## Shotgun (Apr 21, 2021)

Woohoo!  This is gettin' real, y'all!

I've got a few questions.   

1) The Auxiliary Base has two .089 holes.  I assumed they would be for locating pins, but didn't see corresponding holes in the Main Base.  What's up with that?

2) The slots for the locating blocks on the bottom of the Main Base.  Any reason they can't run the length of the base?

3) The hole for the Trunnion on the Main and Auxiliary Bases would need to be at the exact same height.  The numbers on the drawing aren't adding up. I assumed I would clamp the bases together for final boring of the trunnion hole, using the bottom to level set them.


----------



## Flyinfool (Apr 21, 2021)

Shotgun said:


> Woohoo!  This is gettin' real, y'all!
> 
> I've got a few questions.
> 
> ...


1) The two .089 holes are for locators for pins to be installed at assembly. It will take some messing around to get the trunion exactly lined up and at that time the owner of that Dividing Head can drill and pin it to make alignment perfect if it is ever taken apart for cleaning. These will allow for either an .093 or .125 pin. I made the screw holes with some extra clearance to allow for adjustment. There are just 2 many dimensions between to realistically have them just line up. 

2) No reason they can not run the length and width of the base

3) I made the Aux base short on the bottom to be sure that it will not protrude below the bottom of the base and cause a tilt when set on the table. If you are making both parts and can line bor both holes then you could screw and pin the  2 parts together before boring. I was not sure if you could bore 6 inches deep.

There will be some parts that are designed and toleranced expecting that 2 different people will be making them, IF the same person is making both parts the tolerances can be opened up a lot and that one perrson can just make them to fit together. This is part of what I will be talking to each of you on once I get the first pass of the drawings done.


----------



## ttabbal (Apr 21, 2021)

Flyinfool said:


> OK, Here are the drawings so far. These are NOT finished drawings. Do NOT try to make parts from them. Critical dimensions are still being adjusted and missing info has yet to be added. These are for reference only. There are some parts of the project that I have plans for changes to.



Looking good! 

On the Trunion, I could do the holes on the end with a rotary table, but it calls out a 5 degree taper. The dimensions look close to a #2 taper pin, but the angle is wrong, those are more like 0.6 degrees. 1/4" per 12" from mcMaster. Any idea where to get a 5 degree taper reamer? I see some for guitar makers, but those are made for wood. It looks like tapered end mills are a possibility... 

I don't have the ability to engrave the text though. Does someone have a CNC rotary axis to do that bit? I might be able to get some cermark or similar and laser it on, but it wouldn't be as durable as an engraved marking. I'm not sure my laser rotary setup is precise enough though.


----------



## Flyinfool (Apr 21, 2021)

Those tapered holes were based on a 3/16 x 5° per side center cutting tapered end mill. I chose 5° because it was the lowest cost tapered end mill from McMaster Carr. If I weere doing it I would predrill most of the hole and then just finish the taper and bottom with the end mill.








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The pin that drops into the hole will a part that someone here will make so it can be any angle.

The text does not necessarily need to be engraved on the trunion, it could be stamped. For accuracy It would be nice to have the lines engraved. In reality, those lines are only good as a reference for something that is not a critical angle, If your angle is critical you would want to indicate it in anyhow.


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## ttabbal (Apr 21, 2021)

Cool. That sounds like it would work. I'm looking forward to seeing things progress.


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## Flyinfool (Apr 22, 2021)

The engraving of the lines could be done with your smallest end mill.
Just use the corner of the end mill with it set 45° off axes to make a 90° V notch for the line. The smaller the end mill the less the run out at the end of the line.

Did this make sense? I can picture it in my head but not sure how to put it in words.


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## Flyinfool (Apr 23, 2021)

Update on the drawings so far. These are NOT finished drawings. Do NOT try to make parts from them. Critical dimensions are still being adjusted and missing info has yet to be added. These are for reference only. There are some parts of the project that I have plans for changes to.
I did not update the step file as the changes made so far are of the a couple thou here and there as I am adjusting fits and tolerances.


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## Shotgun (Apr 23, 2021)

Loving it.  

For the Auxiliary Base, the top is a 1.5" radius, while the Trunnion hole is 2.75" diameter.  That leaves a 1/4"x1/8" strip to hold the Trunnion and stop if from vibrating.  Am I wrong to think this is a mite delicate?  From the STEP model, it looks like there is room to make it thicker.  Advisable?

That large, outside, partial radius is going to be the most difficult part for me, and the part I'm most interested in completing successfully.

The Spindle Lock and the Worm Mount are called out as .750".  That is the nominal thickness of the material I'm getting and doesn't allow any room to clean it up.  I don't think it will matter if they are slightly under, and .730" will allow me face off up to .010" from each side.  Could we change this dimension to .74" without causing problems? (so that the allowable will be between .750" and .730".)

I just got another treadmill to rob the motor from.  I think I'm going to use part of the walking platform and the current drawings to start working out my order of operations.  I got all the parts for my uncle's shop press made, and I'm taking it to him Sunday.  I'll be bringing back a large supply of 3/4" structural steel.


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## Flyinfool (Apr 24, 2021)

@Shotgun, Its all your fault........  
I made the top of the Aux Base thicker and somehow it corrupted the drawing So now I get to redraw.......

I could add some more difficult challenges if you want me to.

I have not looked at the thickness changes yet, I am still recovering from the 1st change......


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## Shotgun (Apr 24, 2021)

:-(
Just remember that these computers were DESIGNED to make our lives easier.
And one new challenge per project is quite enough.


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## Flyinfool (Apr 24, 2021)

OK I got the blown up drawings fixed, all the requested changes implemented, and even got a few more drawings done.
If there is anything that looks like it may cause you dificulty on the parts you are making, let me know ASAP so we can work it out.

I'm getting close, only 5 more part drawing to draw, and 4 assembly drawings to do.

Update on the drawings so far. These are NOT finished drawings. Do NOT try to make parts from them. Critical dimensions are still being adjusted and missing info has yet to be added. These are for reference only. There are some parts of the project that I have plans for changes to.


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## ErichKeane (Apr 24, 2021)

Cool, its getting there!  I could definitely be up for a few more parts.  I love ID single-pointing, so maybe I'll do the spindle nut and a couple of the others.

Question I had... Is there a reason the worm gear itself is a separate part from its shaft (it goes on DH13?).  I could probably just as easily make DH13 out of 1 piece and single point the worm on the end just as easily.  What do you think?  If possible, it might save time in the long run.


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## Brento (Apr 24, 2021)

Cant wait to see my drawings


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## Flyinfool (Apr 24, 2021)

That would be possible, The original plan was to buy a foot long chunk of the worm shaft and just cut off the 1 inch chunks. If you think you can single point the worm I can make that change easy enough. That will also eliminate the shaft and the worm washer and the SHCS screw in the end.


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## Flyinfool (Apr 24, 2021)

@Brento Unfortunately for you your parts just happen to be that last 5, and one of the assemblys. Just a fluke of the way they got numbered. I am doing them in numerical order.


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## ErichKeane (Apr 25, 2021)

Flyinfool said:


> That would be possible, The original plan was to buy a foot long chunk of the worm shaft and just cut off the 1 inch chunks. If you think you can single point the worm I can make that change easy enough. That will also eliminate the shaft and the worm washer and the SHCS screw in the end.


I actually haven't single-pointed ACME yet, so I'm tempted to try   I've been wanting to try a tool-grind/etc and go for it, so this would be a great excuse to try it.

It looks like the worm shaft and worm-washer are unassigned, so if you give me all 3 parts I'll just try to make it as a 1 piece.  If I fail, its easy enough to fall back  Though, it isn't clear to me where the washer goes...


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## Brento (Apr 25, 2021)

No biggie. Looking forward to them!  Looking great and you are doing an amazing job!

Edit: i just got a 100$ worth of a bunch of material so im ready at my end for the most part. Lots of plastics as well.


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## rwm (Apr 25, 2021)

Looking very complex!
Single pointing the worm will be challenging on a light machine due to chatter. Do a test run first maybe? As I recall Erich  has a pretty robust machine so it might be fine. What about silver soldering a section of worm over a shaft? If the fit was tight it would be very concentric and a solid joint.
I hope you guys don't mind if I play "devils advocate" and try to find issues with the design. I think that could be helpful before parts are made.
Robert


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## ErichKeane (Apr 25, 2021)

rwm said:


> Looking very complex!
> Single pointing the worm will be challenging on a light machine due to chatter. Do a test run first maybe? As I recall Erich  has a pretty robust machine so it might be fine. What about silver soldering a section of worm over a shaft? If the fit was tight it would be very concentric and a solid joint.
> I hope you guys don't mind if I play "devils advocate" and try to find issues with the design. I think that could be helpful before parts are made.
> Robert


I have a 16", 5000lb lathe   Not a very light machine!  I presume light cuts + extra care grinding the cutter (I might use the surface grinder?) should make it turn out alright.


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## ErichKeane (Apr 25, 2021)

Another Idea I had BTW!  I wonder if we could convince @vtcnc or the other admins to let us have a sub-forum for build threads for all of the components?  Or did you just want to use this one for it?  It might be a little less organized with everyone in the same thread though.


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## Shotgun (Apr 25, 2021)

ErichKeane said:


> Cool, its getting there!  I could definitely be up for a few more parts.  I love ID single-pointing, so maybe I'll do the spindle nut and a couple of the others.
> 
> Question I had... Is there a reason the worm gear itself is a separate part from its shaft (it goes on DH13?).  I could probably just as easily make DH13 out of 1 piece and single point the worm on the end just as easily.  What do you think?  If possible, it might save time in the long run.


The only point of care is that the worm has to be  a nearly perfect fit to the gear it is mating to.  We were getting around that by hobbing the gear with a piece cut from the acme rod.  If they are made separately. . .


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## Flyinfool (Apr 25, 2021)

I was thinking on the same lines. It would be possible to make a new hobb from a single pointed gear shaft.



rwm said:


> Looking very complex!
> Single pointing the worm will be challenging on a light machine due to chatter. Do a test run first maybe? As I recall Erich  has a pretty robust machine so it might be fine. What about silver soldering a section of worm over a shaft? If the fit was tight it would be very concentric and a solid joint.
> I hope you guys don't mind if I play "devils advocate" and try to find issues with the design. I think that could be helpful before parts are made.
> Robert



Dont mind at all, Just bear in mind that there are compromises made to accommodate the capabilities of the individuals in the project and to keep cost down.


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## ErichKeane (Apr 25, 2021)

Flyinfool said:


> I was thinking on the same lines. It would be possible to make a new hobb from a single pointed gear shaft.
> 
> 
> 
> Dont mind at all, Just bear in mind that there are compromises made to accommodate the capabilities of the individuals in the project and to keep cost down.


I figured I would just machine the worm gear to the same dimensions as the hobb...


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## vtcnc (Apr 26, 2021)

Do you guys still want sub-forums? I think this is a great idea BTW @ErichKeane.


Sent from my iPhone using Tapatalk


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## Flyinfool (Apr 26, 2021)

I can see pros and cons to having sub forums for this. I guess I am not sure what you are suggesting for us to do with the sub forums?

PS, I have all the part drawings down on paper so to speak. I am now teaching myself how to do the assembly drawings in SolidWorks. and then I can print them all and go thru to check every mating part to be sure they will fit correctly. This is the step where I will make a lot of changes of a thou or 2 here and there and decide on the tolerances needed for each part. Some parts I may add notes on order of operations when it matters.

I am seeing light at the end of the tunnel for the design process.
I hope it is not the train coming in from the other side.


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## ErichKeane (Apr 26, 2021)

Flyinfool said:


> I can see pros and cons to having sub forums for this. I guess I am not sure what you are suggesting for us to do with the sub forums?
> 
> PS, I have all the part drawings down on paper so to speak. I am now teaching myself how to do the assembly drawings in SolidWorks. and then I can print them all and go thru to check every mating part to be sure they will fit correctly. This is the step where I will make a lot of changes of a thou or 2 here and there and decide on the tolerances needed for each part. Some parts I may add notes on order of operations when it matters.
> 
> ...


The thought was that we could have a sub-forum where we could all post our 'part build threads'.  That way we don't get them all mixted into the project area.


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## Shotgun (Apr 27, 2021)

ErichKeane said:


> The thought was that we could have a sub-forum where we could all post our 'part build threads'.  That way we don't get them all mixted into the project area.


I would end up jumping around between threads to keep track of everything and make sure I didn't miss out on anything.


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## Flyinfool (Apr 29, 2021)

Update on the drawings so far. These are NOT finished drawings. Do NOT try to make parts from them. Critical dimensions are still being adjusted and missing info has yet to be added. These are for reference only. There are some parts of the project that I have plans for changes to. Some parts as drawn are size on size and that needs to be changed for proper clearance and fits. I usually try to make holes a standard size and make the machined shaft the odd size so that standard size drills and reamers can work.

If there is anything that looks like it may cause you difficulty on the parts you are making, let me know ASAP so we can work it out.

This is all the parts down on paper so you can get an idea of what you are getting into with the parts. The only drawing yet to do is the main assembly. I am holding off on that until I am done with everything else. I have not been keeping up with the changes as to who is making what on the BOM. I will have to read back thru this thread to figure that all out to know what is and is not spoken for.

I have 2 job interviews yet this week so I will be mostly studying for those. I am hoping to get the drawings and model finalized some time next week. We are getting close now.

There are some parts the will require machining after assembly to avoid needing incredibly tight tolerances to get the parts to mate if they were machined complete at the part level.


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## Shotgun (Apr 29, 2021)

I've started work on the base already.  I had to take my uncle the shop press that I built for him out of scrap steel.  You can see it in the background, on the right edge of the video.  It's a 2-hour drive, that I don't make lightly.  So I had him cut the steel to length with his chop saw.  We started by cutting a piece off the 20' length, and then chopped it to size.   I have to do quite a bit of juggling to get this big steel in my 4x6 bandsaw, but check this out.









						Thick angle vs Chop Saw
					

Here we're cutting 6"x6"x3/4" structural steel angle with a 12" metal chop saw.




					rumble.com
				




He cut it just slightly oversized.  He has had that blade for 5 years, and it was getting near EOL, so this is what I ended up with:


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## Shotgun (Apr 29, 2021)

Flyinfool said:


> If there is anything that looks like it may cause you difficulty on the parts you are making, let me know ASAP so we can work it out.


Page 5:  What is the R.750 cutout on the left side of the right drawing?  I can't make out what it is used for.

Page 11: Is there any reason that the screws for the blocks can't be through holes?

Page 22:  The walls for the worm side of the mount look mighty thick.  Is this a part we would expect to clamp down on and then never move again, or would it be adjusted regularly?  The worm side would be set-n-forget, I would expect, so the thick walls are just fine.  How much force will need to be applied to move that 3/8" thick wall through such a short radius?  Maybe I could make the part as is, and then mill material off of each of the angled sides till the forces are reasonable if necessary?


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## Flyinfool (Apr 29, 2021)

Shotgun said:


> Page 5:  What is the R.750 cutout on the left side of the right drawing?  I can't make out what it is used for.
> 
> Page 11: Is there any reason that the screws for the blocks can't be through holes?
> 
> Page 22:  The walls for the worm side of the mount look mighty thick.  Is this a part we would expect to clamp down on and then never move again, or would it be adjusted regularly?  The worm side would be set-n-forget, I would expect, so the thick walls are just fine.  How much force will need to be applied to move that 3/8" thick wall through such a short radius?  Maybe I could make the part as is, and then mill material off of each of the angled sides till the forces are reasonable if necessary?


Page 5: That .750 cutout is clearance where the worm shaft goes thru.

Page 11: They could go thru. I made them blind so that swarf would not accumulate in them.

Page 22: The big hole will be clamp and forget. Once aligned it will never be used again. The small hole will only be used to engage the worm and never changed again unless you want to disengage the worm to use the rapid indexing. Not used during normal operations. I was going to make the walls thinner but wanted to keep the straight line to ease machining. I will look at that some more, or I could just let you go ahead and do some trials to get the right "feel", and then I can make the drawings match the part. (I have often had to make the drawing package match what the shop ended up actually making in the real world too)


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## rwm (Apr 29, 2021)

I have the same chop saw. The thing is amazing.
Robert


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## Weldingrod1 (Apr 29, 2021)

Single pointing ACME isnt too bad. Check that you can hit the pitch: it's probably really coarse. Last one I did required gears on my Harding! And the retract didnt pull back enough...

Sent from my SM-G892A using Tapatalk


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## Flyinfool (Apr 29, 2021)

I am not sure why the section view on the Trunion Assy is missing from the drawing file.
Here is a new one of that sheet.


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## Brento (Apr 29, 2021)

I just wanted to get a feel on everyones opinion. I checked on my parts which includes all of the indexing crank pieces which are parts 32-36. I can do most of the parts right from the start however my concern is the milling work. I cant get to doing the milling work atleast until maybe end of june depending on the weather. Now is everyone ok if with that amount of waiting time possibly if it does get held up on my side? I dont mind doing the work, in fact i want to do it but if it is a problem i understand then.


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## ErichKeane (Apr 29, 2021)

Brento said:


> II just wanted to get a feel on everyones opinion. I checked on my parts which includes all of the indexing crank pieces which are parts 32-36. I can do most of the parts right from the start however my concern is the milling work. I cant get to doing the milling work atleast until maybe end of june depending on the weather. Now is everyone ok if with that amount of waiting time possibly if it does get held up on my side? I dont mind doing the work, in fact i want to do it but if it is a problem i understand then.


 I gotta think this is going to take a few months for all of us to build anyway, so I wouldn't sweat it.


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## Brento (Apr 29, 2021)

Ok i just dont want to let the group down or anything ya know?


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## Brento (Apr 29, 2021)

if no one signs up for them i can do the plug brass and the handle. I can prob do the handle by hand if it isnt really critical.


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## Flyinfool (Apr 29, 2021)

Not much of the handle is critical.


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## rwm (Apr 29, 2021)

Wow. The drawings look great! You guys picked a tough project to start on though. 
Robert


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## Brento (Apr 29, 2021)

It will be a tough project i am sure but it is going to be nice to have one built with alk of you guys instead of a mass produced one. Makes it all sentimental-y lol. I know the handle isnt critical but as long as that drill point is not critical i can do it by hand and save some time for others doing more important things.

Edit: any ideas for material yet or is that part of the last go through on the drawings.


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## Flyinfool (Apr 29, 2021)

Some parts have material listed in the title block, Some of the title blocks still need to be edited. That is why I keep putting in to NOT start making stuff from these prints, they are just so you can start planning.
Some list a specific material, some list several choices and some say any metal. WHen I refer to any metal, it could be steel, stainless, aluminum, brass or a few others that are machinable, pretty much whatever you have on hand or you think will look good. Obviouslt it does not include metals like mercury, lead, beryllium, uranium, or other potentially hazardous or extremely soft/weak metals.


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## ttabbal (Apr 29, 2021)

I'm not in a rush, so if people need some time to get it done, I'm good. 

For the trunnion, I think I mentioned before that the material I have is 3". I'll need some room to clean up the OD. I can turn a piece and mic it if it matters. I just want to make sure it will work. I don't see a problem with it from the drawings, but I could be missing something.


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## ttabbal (Apr 29, 2021)

Bummer, I was going to use depleted uranium for maximum durability!


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## Flyinfool (Apr 29, 2021)

The OD of the trunion is not critical, as long as you are not cleaning up potholes.


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## Brento (Apr 29, 2021)

What was the issues with the callouts and dimensions in yellow?


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## Shotgun (Apr 29, 2021)

Brento said:


> It will be a tough project i am sure but it is going to be nice to have one built with alk of you guys instead of a mass produced one. Makes it all sentimental-y lol. I know the handle isnt critical but as long as that drill point is not critical i can do it by hand and save some time for others doing more important things.
> 
> Edit: any ideas for material yet or is that part of the last go through on the drawings.


Don't go getting soft on me, @Brento.  I might cry.


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## rwm (Apr 29, 2021)

I fear that when you cut the slot in the trunnion it will deform due to internal stresses. Perhaps you should cut the slot first, bolt on the end cap and then take it to final OD? Thoughts? Also, just use regular Uranium. It will be fine as long as you don't ship 4 items in the same box.
Robert


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## Flyinfool (Apr 29, 2021)

Brento said:


> What was the issues with the callouts and dimensions in yellow?




I have no clue why some dimensions are a weird color. They are all black on the original drawing, it must have been something in the conversion to PDF.


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## Flyinfool (Apr 29, 2021)

There you all go, now you want your tools to also provide the shop lighting......

This will take some recalculations and redesign for critical mass.


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## Shotgun (Apr 29, 2021)

ttabbal said:


> I'm not in a rush, so if people need some time to get it done, I'm good.
> 
> For the trunnion, I think I mentioned before that the material I have is 3". I'll need some room to clean up the OD. I can turn a piece and mic it if it matters. I just want to make sure it will work. I don't see a problem with it from the drawings, but I could be missing something.


As @Flyinfool said, the OD isn't really critical, but the shoulders that mate to the base are two of the more critical dimensions, I would think.  And the exact dimension isn't so critical as that the two match.

I bought a Milwaulkee hole saw with carbide teeth. It comes with an innovate arbor that I can build an adapter directly into an MT3 taper for super rigidity.  If it tests out with as good a finish as I think it will give,  I'd like to drill a hole in a scrap plate and mail that to @ttabbal. Until this project is finished, that hole saw will be dedicated to that job.


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## Flyinfool (Apr 29, 2021)

I can see using a hole saw to rough out the holes, I never saw one that gave near a nice enough surface finish compared to a bored hole. That saw will be chewing thru 7 inches of steel for this project. I will be curious to see how it performs when more rigidly mounted.


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## ttabbal (Apr 29, 2021)

Shotgun said:


> As @Flyinfool said, the OD isn't really critical, but the shoulders that mate to the base are two of the more critical dimensions, I would think.  And the exact dimension isn't so critical as that the two match.
> 
> I bought a Milwaulkee hole saw with carbide teeth. It comes with an innovate arbor that I can build an adapter directly into an MT3 taper for super rigidity.  If it tests out with as good a finish as I think it will give,  I'd like to drill a hole in a scrap plate and mail that to @ttabbal. Until this project is finished, that hole saw will be dedicated to that job.



Sounds good to me. A gauge is always welcome. I'll do some testing as well to verify stress doesn't cause any problems. I don't think the wife will take well to me stress relieving it in the oven.


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## Flyinfool (Apr 29, 2021)

As I mentioned in another post.
Do it when she is not home or learn to duck.......


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## ErichKeane (Apr 30, 2021)

I noticed an odd dimension with the shaft and worm-wheel.  It looks like the area for the worm wheel + washer is supposed to be .938 long.  However, the worm gear itself is 1" long (plus .150 for the washer).  Are we expecting the bolt to go through both and then be 'free' between the two for 200 thou?  

If i opt to instead change to just threading the shaft (or press fit or loctiting or etc) on the worm gear, is just 1" off the .70 shoulder fine?

Also, of interest, the difference in size between the OD of the shoulder and the OD of the washer is interesting.  .70 for the shoulder, and .700 for the worm  


Additionally, I was thinking I could start ordering materials.  What to you guys thing about them?  Due to the gear-hobbing I was sort of hoping to make the worm-wheel out of aluminum, but if that isn't going to work, thats fine too.  Are we worried about the teeth getting broken if it is just aluminum?  Or should we do 1018/12L14/etc?


  For the shaft + worm, I would think 1018/12L14 would be fine whether we did aluminum or steel for the wheel.


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## Flyinfool (Apr 30, 2021)

ErichKeane said:


> I noticed an odd dimension with the shaft and worm-wheel.  It looks like the area for the worm wheel + washer is supposed to be .938 long.  However, the worm gear itself is 1" long (plus .150 for the washer).  Are we expecting the bolt to go through both and then be 'free' between the two for 200 thou?
> 
> If i opt to instead change to just threading the shaft (or press fit or loctiting or etc) on the worm gear, is just 1" off the .70 shoulder fine?
> 
> ...


The bolt and the washer serve no purpose other than to mount the worm to the shaft. The shaft is shorter than the worm to be sure that it all clamps solid. There is nothing special about the 1/16 clearance. Just a number pulled out of thin air that would allow me to put a very loose tolerance on the dimension and be sure it will still work. IF you decide to single point the thread, the washer and bolt will be gone and the shaft will end at the gear.

.70 vs .700 is part of the checking of fits and tolerances that I have yet to do.

If the driven gear was made out of aluminum my biggest worry will be wear. especially if you happen to be indexing a steel gear and those chips will easily damage an AL gear. You could probably get away with 7075 or 2024 AL, I think 6061 will be to soft. I have never machined 7075 so I do not know how it is to work with. If the gear is made from steel, I think the hob will need to be properly heat treated to hold up to cutting steel. The ideal material would be brass. it is harder than AL but still machines easily and is purdy. BUT brass ain't cheap. 12L14 and 7075 AL are about the same cost.

I would not use 1018 for the worm + shaft, it usually does not leave a nice surface finish as machined for a precision part with bearing surfaces.


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## ErichKeane (Apr 30, 2021)

Flyinfool said:


> The bolt and the washer serve no purpose other than to mount the worm to the shaft. The shaft is shorter than the worm to be sure that it all clamps solid. There is nothing special about the 1/16 clearance. Just a number pulled out of thin air that would allow me to put a very loose tolerance on the dimension and be sure it will still work. IF you decide to single point the thread, the washer and bolt will be gone and the shaft will end at the gear.
> 
> .70 vs .700 is part of the checking of fits and tolerances that I have yet to do.
> 
> ...



Thanks!  That all makes sense. Brass ends up being silly-expensive for this I think... Even the aluminum and steel are both ~$150 as far as I can tell, unless there is some way to get this from some other material (or from another source, hints welcome!).

As far as the shaft, I'm leaning toward 12L14, it is both cheaper and much nicer to work with


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## Shotgun (Apr 30, 2021)

The gear isn't supposed to be taking any real stress.  Right?  It is just supposed to dial the spindle to the correct position while not under load, and then the spindle lock is engaged?  Even if someone is making a spiral cut, there still isn't much load on the gear.

The one I made was out of 7075.  Got the material from eBay for approximately $2/lb.  It now looks like the price is ~$2.50/lb.  Do a search for "aluminum scrap drops".  I did have to round off the square stock.


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## ttabbal (Apr 30, 2021)

Hey, if I'm using uranium, I expect you to use at least titanium! Maybe plutonium, should give a nice glow with the uranium parts.  

I don't see any issue with 12L14. I don't think there would be a ton of stress on the parts. 7075 is nice to work, but I don't think it would hold up nearly as well. Sure you don't want to use iconnel?

I haven't tried it with a gear, if @Shotgun thinks his is up to it, I'm good.


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## Shotgun (Apr 30, 2021)

ttabbal said:


> I haven't tried it with a gear, if @Shotgun thinks his is up to it, I'm good.



I think I mailed that part to @ErichKeane?  Chip ingress is an important point that I hadn't considered. 
I only had a second for a quick search, but it looks like brasses have a Brinell hardness in the high 70's, while 7075 is in the high 80's.

Edit:  Found better source.  The best bronze is aluminum bronze with a rockwell-b hardness of 77.  7075 aluminum's rockwell-b is 75.  I'd say that choice is a to-may-toe/to-mah-toe sort of thing.


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## ErichKeane (Apr 30, 2021)

Shotgun said:


> I think I mailed that part to @ErichKeane?  Chip ingress is an important point that I hadn't considered.
> I only had a second for a quick search, but it looks like brasses have a Brinell hardness in the high 70's, while 7075 is in the high 80's.


Yep, I'm doing that part   I have the blank you made.  The thickness is about right, but the diameter is too small (it is spec'ed at 3.600 diameter, which is part of what makes it so expensive).


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## rwm (Apr 30, 2021)

I have a ton of yellow mystery brass for casting that I will likely never use. Would a cast brass worm gear blank be good? Most of the brass is probably 60-70% zinc. I could add copper. Cast blanks would likely have small casting defects that we would have to accept.
Robert


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## ErichKeane (Apr 30, 2021)

rwm said:


> I have a ton of yellow mystery brass for casting that I will likely never use. Would a cast brass worm gear blank be good? Most of the brass is probably 60-70% zinc. I could add copper. Cast blanks would likely have small casting defects that we would have to accept.
> Robert


I'd imagine that would be alright, what do you think guys?  I was actually thinking that if I got my heat-treat-kiln together, maybe I could also put together a mold and cast brass (apparently 1900 degree pour temperature?) and just do that instead.  But I'm probably a few months from being able to do that.


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## ttabbal (Apr 30, 2021)

ErichKeane said:


> I'd imagine that would be alright, what do you think guys?  I was actually thinking that if I got my heat-treat-kiln together, maybe I could also put together a mold and cast brass (apparently 1900 degree pour temperature?) and just do that instead.  But I'm probably a few months from being able to do that.



Sounds good to me!


----------



## rwm (Apr 30, 2021)

I think it will be hard to do brass in a heat treat kiln although you could try it. My casting equipment is in storage at the moment or I would jump on this. One thing I noticed is the large size of the gear. It is .750 thick x 3.6". I would probably consider a 1 x 4" blank so you could machine off the cast surface. That is a big chunk of brass. I wonder if casting a brass cylinder and using that as the stock would be easier?
Robert


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## ErichKeane (Apr 30, 2021)

rwm said:


> I think it will be hard to do brass in a heat treat kiln although you could try it. My casting equipment is in storage at the moment or I would jump on this. One thing I noticed is the large size of the gear. It is .750 thick x 3.6". I would probably consider a 1 x 4" blank so you could machine off the cast surface. That is a big chunk of brass. I wonder if casting a brass cylinder and using that as the stock would be easier?
> Robert



Either would work for me!  I can always toss it on the bandsaw to make them smaller.  The 1x4 blanks would likely be great too!  I think we're currently at making 7 of these, so that plus a couple of "oopsies" might be nice


----------



## Flyinfool (Apr 30, 2021)

There is a lot of metal in this project, and a number of heavy parts that will not be cheap just for the stock to make it.

I looked at dropping the OD of the gear to 3.475 to allow 3.50 stock instead of 3.75 stock. This change would cut about $30 off the cost of the bar, it would also reduce the tooth contact area by almost half. This would still include 3/8 of an inch down the center of the gear with full tooth contact. I think It will still work but will be right on the edge of clean engagement.


----------



## ErichKeane (Apr 30, 2021)

Flyinfool said:


> There is a lot of metal in this project, and a number of heavy parts that will not be cheap just for the stock to make it.
> 
> I looked at dropping the OD of the gear to 3.475 to allow 3.50 stock instead of 3.75 stock. This change would cut about $30 off the cost of the bar, it would also reduce the tooth contact area by almost half. This would still include 3/8 of an inch down the center of the gear with full tooth contact. I think It will still work but will be right on the edge of clean engagement.


Ouch... Not sure that is worth it.


----------



## Shotgun (Apr 30, 2021)

You wouldn't need to cast a cylinder as much as a REALLY thick walled tube.  There is a lot of material coming out of the middle there.  Could almost use a piece of pool noodle if doing lost wax casting.

If your kiln won't do it, might someone on the forum lend a hand?


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## rwm (May 1, 2021)

Let me check my brass inventory firsthand. I am sot setup for lost wax. I would use sand casting. The process would probably involve making a match plate with mahogany patterns. Perhaps 3 or 4 patterns per plate which would end up being a very large casting flask. I have an example somewhere.
R


----------



## Weldingrod1 (May 1, 2021)

Btw, 7075 machines very nicely! Frankly easier to work with than 6061.

Sent from my SM-G892A using Tapatalk


----------



## ErichKeane (May 1, 2021)

Looks like a 7075 plate from midwest supply is at least not awful. I should be able to get all the pieces out of a 12*12 plate (assuming my math is right) and they have 7/8 plate available for $120+shipping. So if brass doesn't work out, I could always do that!


----------



## Ianagos (May 1, 2021)

I’ll check and see if I have some bronze or aluminum bronze sitting around. You won’t enjoy machining the aluminum bronze but it’s very strong


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## rwm (May 1, 2021)

Jeff- I must say your plans are a work of art. Great job so far.
Robert


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## Flyinfool (May 1, 2021)

Thanks Robert,


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## Flyinfool (May 1, 2021)

ErichKeane said:


> Looks like a 7075 plate from midwest supply is at least not awful. I should be able to get all the pieces out of a 12*12 plate (assuming my math is right) and they have 7/8 plate available for $120+shipping. So if brass doesn't work out, I could always do that!



Another place to check is the Random Rack at Howard precision. They sell drops from jobs they have run at really good prices. Some alloys are as low as $1 per pound. You just have to look thru what they have to find something you can use. You might end up with a much bigger chunk than you need at less money and have some left for your stock rack. But call them before ordering, shipping can get pricey on big heavy items.





__





						Random Aluminum Pieces & Parts | Aluminum Flat Bar & Tooling Plate Suppliers - Howard Precision Metals Inc
					

Howard Precision Metals has a variety of random metals in stock and ready to cut your specifications. Call our sales department to lock in your random piece at 800-444-0311.




					www.howardprecision.com
				




If you go from plate I am guessing that about a 3.75 hole saw slug will be close to the starting size you will need. And it will by default have a 1/4" hole on center to start from.

I just remembered that I have a big chunk of brass tube in the basement, Unfortunately it is only 2.75" OD x .9375 ID x 13 long.


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## ErichKeane (May 1, 2021)

Flyinfool said:


> Another place to check is the Random Rack at Howard precision. They sell drops from jobs they have run at really good prices. Some alloys are as low as $1 per pound. You just have to look thru what they have to find something you can use. You might end up with a much bigger chunk than you need at less money and have some left for your stock rack. But call them before ordering, shipping can get pricey on big heavy items.
> 
> 
> 
> ...


I found a hunk of mystery aluminum plate in my junk pile, but it is 3/4" thick, and I know the gear is supposed to be .750 +/- .005, so I presume that wouldn't quite cut it...  Also not positive that it is big enough, I measured 1 side as 10" i think, and the other as 12". So unless I could tessalate, it would be a no-go.

I have a metal supermarkets about an hour drive away I could try as well (where I got the plate).  Still hopeful on someone being able to do the casting though, it seems like a cool addition to the project  Otherwise, Metal Supermarket or whatever can work too.


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## Flyinfool (May 1, 2021)

Howard precision is local to me just 21 miles. Depending on what you get and what shipping would be, I could pick it up (Assuming the will call is still open with COVID), cut it smaller to fit into a USPS flat rate box or 2.


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## rwm (May 2, 2021)

The worm gear is called out as .750 but would it really matter if it was .730 after cleanup?
Robert


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## Flyinfool (May 2, 2021)

.730 would not matter. If you are starting from plate the as supplied finish would probably be fine to.


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## erikmannie (May 2, 2021)

Brento said:


> I just wanted to get a feel on everyones opinion. I checked on my parts which includes all of the indexing crank pieces which are parts 32-36. I can do most of the parts right from the start however my concern is the milling work. I cant get to doing the milling work atleast until maybe end of june depending on the weather. Now is everyone ok if with that amount of waiting time possibly if it does get held up on my side? I dont mind doing the work, in fact i want to do it but if it is a problem i understand then.



I am okay to go with the flow. I will only have one day available a week to work on the parts myself.


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## Brento (May 2, 2021)

erikmannie said:


> I am okay to go with the flow. I will only have one day available a week to work on the parts myself.


I may be down to weekends to do alot of major machining as well. What my plan will be is to machine the parts as far as i can and then have them ready for the mill


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## ErichKeane (May 2, 2021)

Flyinfool said:


> .730 would not matter. If you are starting from plate the as supplied finish would probably be fine to.


Cool, I can re-measure the plate and see what I can get out of it then!

ETA: I also just ordered a couple of foot-long pieces of 12L14 on ebay to make the shafts. If I can single-point the threads well enough, I should be able to take care of a couple of parts with just that! If my aluminum sheet works for the gears, even better.


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## Brento (May 2, 2021)

Question i had for everyone. I have 1" hex stock in aluminum or 3/4" in steel. Would steel be fine for the index body or would everyone be ok for a 1" hex on the index body?  If not i will order some 3/4" aluminum.


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## erikmannie (May 2, 2021)

Brento said:


> Question i had for everyone. I have 1" hex stock in aluminum or 3/4" in steel. Would steel be fine for the index body or would everyone be ok for a 1" hex on the index body?  If not i will order some 3/4" aluminum.



I have no preference on this matter.


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## Flyinfool (May 3, 2021)

Brento said:


> Question i had for everyone. I have 1" hex stock in aluminum or 3/4" in steel. Would steel be fine for the index body or would everyone be ok for a 1" hex on the index body?  If not i will order some 3/4" aluminum.


The latest revision of that drawing calls for brass or steel. The threads are a bit fine for long life in AL. So yes your 3/4 hex steel that you have is fine.


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## Brento (May 3, 2021)

Ok i did not see steel listed for the material so that is why i asked. I know its still isnt final.


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## Flyinfool (May 4, 2021)

AAARRRRRRGGGGGGGGggggggg!!!!!!!!

Solidworks got me again.
Solidworks crashed during a save and corrupted the Drawing file. For some reason it also was able to corrupt the backup files. At least it looks like all of the part files and assy files are good. Solid works is the only program that ever crashes on this computer. At least I printed out all the drawings to mark up for changes so I have a hard copy record of what I had. looks like I will have to redo all the drawings after item 26. No more Mr nice guy, all the drawings are now going to remain separate documents so that this can not happen again, so it will not be one nice drawing file when I post. So I am not sure if I will finish the drawings this week like I had hoped to.


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## ttabbal (May 4, 2021)

Oh no! Sorry you got bit. Thanks for the work you are putting into this. 

I loaded the STEP into Fusion360. It was cool to see the parts together and my part separately.


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## Brento (May 4, 2021)

Ill have to get a program up and running so i can check these parts out.


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## Shotgun (May 5, 2021)

Flyinfool said:


> AAARRRRRRGGGGGGGGggggggg!!!!!!!!
> 
> Solidworks crashed during a save and corrupted the Drawing file.


<SIGH!>

Remember to repeat to yourself, "Computers were DESIGNED to make our lives easier."


----------



## rwm (May 5, 2021)

I started making parts! Sort of...
Here is a pattern for a gear blank.




I hope to cast one of these in brass so we can see how this machines. I have a bucket of random brasses, mostly yellow brass. I will pick the best stuff and try to get close to C360 or perhaps a little higher Cu content.

I was thinking I could thin the area between the hub and the outer edge to reduce the mass. For the first attempt I just started with a simple doughnut with 5 degree draft.

Robert


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## Flyinfool (May 5, 2021)

In a case like this mass may be our friend. More mass will vibrate less during machining of a part.
If this was spinning at high RPM then lightening would help. I think that if you have a real strong arm you might hit 2 RPM on this gear. If the mass reduction is to save material in the casting then go for it. It will not hurt anything, just keep the web at least 1/4 inch thick with a thicker spot for the set screw hole and nice radii in the corners.


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## Flyinfool (May 5, 2021)

I thought I might make it, but I ran out of steam, I put in 12 hours today and got all but the last 5 drawings recreated. My poor little brain has turned to peanut butter. It is nap time...........

Once I get these drawing all done again, then I just have to update the BOM with who is making what so that we know what is left to get done. I think I have the actual content of the BOM in good shape.

We are getting close boys.


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## Brento (May 5, 2021)

So close i can smell the chips flying.  After this round are you wanting to talk to everyone?


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## Flyinfool (May 5, 2021)

As soon as I get the drawings finished and posted I will need to talk to everyone before we open the flood gates. Just in case someone needs changes that might have an effect on a part someone else is making. Unless I forgot something, I think I have been able to accommodate all requests so far.


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## rwm (May 5, 2021)

Flyinfool said:


> In a case like this mass may be our friend. More mass will vibrate less during machining of a part.
> If this was spinning at high RPM then lightening would help. I think that if you have a real strong arm you might hit 2 RPM on this gear. If the mass reduction is to save material in the casting then go for it. It will not hurt anything, just keep the web at least 1/4 inch thick with a thicker spot for the set screw hole and nice radii in the corners.


The main reason to thin the web would be for conservation of material but it would also reduce shrinkage of the casting. This could be an issue with >30% zinc.  I could keep it at 3/8" to allow plenty of room for a set screw.  Lets see how the first one at a full 3/4" looks and feels.
R


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## ttabbal (May 5, 2021)

So, for stress relief, I just picked up a forge. It's propane and has no automation, but could it be useful for that? I got it more for hardening, but it seems like it would get hot enough. If somewhat tricky to hold at temp for long periods.


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## Shotgun (May 6, 2021)

For stress relieving, you want to be at least 100F below the critical temperature, which is generally 1100F to 1200F.  Once reaching temperature, it is only important that you let it cool slowly.  Production shops want to rush that part, because they have to make money.  We're just looking to make a few quality parts.

My electric furnace is almost done, and it will have temperature control.  But , if I were doing it with propane, I'd pack the forge with as much of the steel as I could get in there and heat it to cherry red and hold it there for an hour.  Then cover the forge with as much insulation as I could and go to bed.  

That is the plan for all the thick parts I'm working on. (The fun part will be case hardening the base, after the machining!!)


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## rwm (May 6, 2021)

Is it necessary to case harden the base? Most commercial item bases are probably just cast iron? I would be concerned the part would warp duing hardening?
Robert


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## ttabbal (May 6, 2021)

Stress relief sounds a lot like annealing. Is the difference in the temperature? 

Your idea for the propane forge is basically what I was thinking. Just heat and insulate. Online people talk about burying in sand or ashes, about the same thing as leaving them in the firebrick forge. 

Still learning about heat treatment. I also fell down the casting rabbit hole reading.  might have to get some stuff to try that.


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## Shotgun (May 6, 2021)

rwm said:


> Is it necessary to case harden the base? Most commercial item bases are probably just cast iron? I would be concerned the part would warp duing hardening?
> Robert


I fully expect it to warp slightly, but without some hardening the bottom of the base will be susceptible to dings that will interfere with accuracy and the trunnion bearing surface will be susceptible to wear.

Any warpage will be minimized by stress relieving before the rough machining.


----------



## Flyinfool (May 6, 2021)

Shotgun said:


> For stress relieving, you want to be at least 100F below the critical temperature, which is generally 1100F to 1200F.  Once reaching temperature, it is only important that you let it cool slowly.  Production shops want to rush that part, because they have to make money.  We're just looking to make a few quality parts.
> 
> My electric furnace is almost done, and it will have temperature control.  But , if I were doing it with propane, I'd pack the forge with as much of the steel as I could get in there and heat it to cherry red and hold it there for an hour.  Then cover the forge with as much insulation as I could and go to bed.
> 
> That is the plan for all the thick parts I'm working on. *(The fun part will be case hardening the base, after the machining!*!)





rwm said:


> Is it necessary to case harden the base? Most commercial item bases are probably just cast iron? I would be concerned the part would warp duing hardening?
> Robert



If you are going to case harden you will get warpage and dimensional changes. You will need to leave some stock for final machining / grinding AFTER case hardening. The squareness of the base is critical to accuracy.

In use the trunion is only moved during setup and is otherwise clamped down. As hobbyists I doubt if any of us will ever develop measurable wear, hardened or not.

A heat treat oven has been steadily climbing my wish list of tools........Even though I have no idea where I could put it, other than one of your shops....


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## Shotgun (May 6, 2021)

Flyinfool said:


> A heat treat oven has been steadily climbing my wish list of tools........Even though I have no idea where I could put it, other than one of your shops....



If you need a shop to put it in, you can use mine and I'll skip finishing my build.

Just because that is the sort of nice guy I am.


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## Flyinfool (May 6, 2021)

Shotgun said:


> If you need a shop to put it in, you can use mine and I'll skip finishing my build.
> 
> Just because that is the sort of nice guy I am.


If you were my next door neighbor, I might take you up on that...
As far south as you are, cant you do heat treating by just putting the parts outside on a sunny day????


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## Shotgun (May 6, 2021)

Flyinfool said:


> As far south as you are, cant you do heat treating by just putting the parts outside on a sunny day????


That's not funny. . . 'cause it's true.


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## Flyinfool (May 7, 2021)

OK, I am now back to where I was last Monday night. I at least have all the drawings down on paper. AND I now have a set of backups of this whole project, 134 files. Now I can once again start  the process of going thru them to check each feature and dimension so that worst case tolerance stack up the parts will still have proper form, fit, and function. A lot of this step was incorporated while making the drawings that got blowed up.

We are back to seeing daylight at the end of the tunnel, I hope it is not just ANOTHER train coming in from the other side like the last light was.

(CHOOO CHOOOoooo..........)


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## Brento (May 7, 2021)

This weekend i am dusting off the little lathe to get her ready!


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## rwm (May 7, 2021)

I set up my casting stuff today and I tried a test casting. 



	

		
			
		

		
	
Failure! One problem was my rookie mistake. I did not have enough weight on the flask and floated the cope. Duh. Nevertheless, the bulky casting pattern is not idea for yellow brass and would have significant shrink defects anyway. I think I need to thin out the web to about 3/8" and add a shrink bob. That should do it.
Robert


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## rwm (May 8, 2021)

Here is the failed casting cleaned up.




You can see all the flash from the cope lifting. There is a bad shrink defect on the back. This is really yellow brass. It would be nicer to add in some copper but I don't have any available.

The pattern shop worked on this all morning and I think they have got it right.




Robert


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## ErichKeane (May 8, 2021)

I didn't see the defect of the top one, but the flashing wouldn't have been a problem  I don't know how thick you made these, but it still might be usable all the same. I could potentially even just lathe it out into some sort of relief if it wasn't too bad.


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## rwm (May 8, 2021)

Defect was on the back (top, cope side). It was bad. This pattern will also use less metal. It is about .800 thick so you can clean up the sides. 
Robert


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## Flyinfool (May 9, 2021)

OK, Here is the latest drawing package. The drawings are mostly done. Not ready to turn you all loose making chips just yet.

I now need to talk to each of you about the parts that you are making. PM me you number and a good time for me to call. There may be some changes made based on talking to each person. I will also update the BOM with who is making what, There has been some trading of parts and I lost track of who is making what. So at least for the moment the ball is out into all of your courts and out of mine for a change.


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## ErichKeane (May 9, 2021)

I'm also taking D13 Shaft and D20 worm-washer (plus replacing the bolt), since I'm still going to try to make the D13 shaft a single piece with the worm gear.

I might take a few more parts as I get my 'TODO" list a bit shorter


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## Brento (May 10, 2021)

I can do the worm washer and the plug brass. If the worm washer is better to be made with who is making the wheel then that is fine.

Edit: the handle as well.


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## ErichKeane (May 10, 2021)

Brento said:


> I can do the worm washer and the plug brass. If the worm washer is better to be made with who is making the wheel then that is fine.


I think we don't need the worm-washer if I can get the worm gear + D13 shaft  as 1 piece.


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## Brento (May 10, 2021)

True but if not i can do it if it doesnt need to be done with it. I can see where it could be better made with the person making the part but figured id hop in and ask. Im limited in stuff i can do right now so i am trying to take parts i can finish without adding to my load of parts i can half finish until the mill is ready.


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## Shotgun (May 10, 2021)

Brento said:


> True but if not i can do it if it doesnt need to be done with it. I can see where it could be better made with the person making the part but figured id hop in and ask. Im limited in stuff i can do right now so i am trying to take parts i can finish without adding to my load of parts i can half finish until the mill is ready.


You'd could pick up D016, D017, and D018.  They're all small pieces.


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## rwm (May 10, 2021)

I am going to cast at least one gear blank in brass. Assuming that machines OK and you want that material, I may be able to get more involved and work on some other parts. I hope to get that cast on Wednesday.
Robert


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## Flyinfool (May 10, 2021)

Ouch!
I have all of the purchased parts listed with McMaster Carr part numbers. It is not necessary to get them from McMaster but that is a good way to identify what is needed. Today i assembled all of the parts into an order just to see what it was, I figured making 8 Dividing heads. The total order size was $433.48 + tax and shipping.


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## Shotgun (May 10, 2021)

This seems like a good time to use AliExpress.  That's most likely where the hardware is coming from anyway.   I'll put together an order from there, if you'd like.


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## Brento (May 10, 2021)

Shotgun said:


> You'd could pick up D016, D017, and D018.  They're all small pieces.


I can. 17 and 18 i have issue with though due to needing the mill. I just dont want to have to many parts half finished and waiting for a mill


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## Shotgun (May 10, 2021)

Brento said:


> I can. 17 and 18 i have issue with though due to needing the mill. I just dont want to have to many parts half finished and waiting for a mill


I believe the only thing you would need the mill for would be the dowel hole? 
f it gets to that point, you could mail them to me for that feature, and I could assemble them in their parts.


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## Brento (May 10, 2021)

@Shotgun yea it would be the dowel holes for those parts. I have other parts that will be in waiting for a mill so the dowel hole wouldnt be really bad but if it comes to it i will/can send it to you.


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## rwm (May 10, 2021)

Hey, what does Solidworks say the weight of the worm gear would be in brass? How would you feel about machining Everdur (Silicon Bronze 95% Cu)
Robert

Edit:
EVERDUR-1010 is a copper-silicon-manganese alloy having the combination of high strength, workability, good machining qualities and corrosion resistance. It is non-magnetic, highly resistant to fatigue, and can be satisfactorily fusion welded.

I can buy 16 lbs of Everdur for $120 but I also have some laying around. Everdur is WAY easier to cast than high zinc brasses.
Robert


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## ErichKeane (May 10, 2021)

rwm said:


> Hey, what does Solidworks say the weight of the worm gear would be in brass? How would you feel about machining Everdur (Silicon Bronze 95% Cu)
> Robert


Never done it... as long as I can machine it with HSS, I don't mind it, though the concern would be whether Shotgun's homemaid hobber will do the work on it.


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## Flyinfool (May 10, 2021)

Brento said:


> I can. 17 and 18 i have issue with though due to needing the mill. I just dont want to have to many parts half finished and waiting for a mill





Shotgun said:


> I believe the only thing you would need the mill for would be the dowel hole?
> f it gets to that point, you could mail them to me for that feature, and I could assemble them in their parts.



Those dowel holes could also be done in a 4 jaw on the lathe to get the offset.....



rwm said:


> Hey, what does Solidworks say the weight of the worm gear would be in brass? How would you feel about machining Everdur (Silicon Bronze 95% Cu)
> Robert
> 
> Edit:
> ...



If you can give me some rough dimensions of your pattern I can give you that weight. 

The weight I have access to now is the fully machined weight.

For the machined part;
Mass = 1.6052 pounds
Volume = 5.2272 cubic inches


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## Brento (May 10, 2021)

I could but i dont see a 4 jaw for this little lathe in my future any time soon

Edit: not to mention i would have to find one as well for my lathe at a decent price.


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## rwm (May 12, 2021)

Success.





Robert


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## Shotgun (May 12, 2021)

Oooo!

Aaaaah!


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## Flyinfool (May 12, 2021)

HEY!!!
That looks kind of like a gear blank.


----------



## ttabbal (May 12, 2021)

Nice! My evil plot is to try learning casting here soon. I expect to make a lot of unrecognizable blobs to start with.


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## rwm (May 12, 2021)

All in all, this is a decent casting. The bottom side looks really good machined:




The top side shows some porosity, which is typically where it shows up:



This porosity should not affect function unless we find larger defects during machining. The blank is now .755" thick. You could take off material and possibly machine out the porosity but it is hard to know how deep you would have to go. I would certainly take 5 thou off the porous side and see if it looks better. There is plenty of room on the diameter to machine it down. I could probably improve over time with better technique and flux. I know I could do better with Everdur if we go that route. Whomever is doing the machining should not expect this to machine like extruded C360. Castings will have smaller more brittle chips.

Someone PM with a mailing address so I can get this to you for the next operation!
Robert


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## rwm (May 12, 2021)

I just realized I have some Phospho-copper which may have helped prevent that porosity. If this machines out OK I will start using that.
Robert


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## Flyinfool (May 12, 2021)

Looks pretty good, I do not know much about the intricacies of casting and adding in alloys or fluxes for specific characteristics.
Could the inner and outer rims be made a bit thicker on the top side to allow for the porosity? Although that porosity does not look bad.
The biggest issue will be if our home made hobb can cut that material 8 times. Any sand inclusions will take out the hobb quick. You will need to very clean on the sprue and vents to avoid any loose sand getting into the parts.

But that sure looks like fun.......


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## rwm (May 13, 2021)

The porosity is likely gas. I doubt you will see any sand inclusions although that is always possible. There were no sand inclusions on the top surface. Phospho-Cu should remove the gas. There are some other tricks I can try with gating. If any lurkers have some brass or copper they would like to contribute I can improve the alloy. That cast part should have a composition very close to C360.
Robert


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## Ianagos (May 13, 2021)

Rwm are brass chips of any help? might be able to get a few pounds and maybe some off cuts of that would help. May not be worth the shipping though? How much is brass per pound normally?


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## Ianagos (May 14, 2021)

I cut the parts and there wasn’t much chips left they really got scattered.







Im ready to cut my parts aswell. And if anybody needs any help let me know I’ll try to help if I can.


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## rwm (May 14, 2021)

Chips are really not helpful. The surface area to volume ratio is way too large and they just introduce oxides and other impurities into the melt.
Brass and copper have gotten really expensive. I am seeing brass ingots up to $20/lb depending on the material. For some reason Everdur is less expensive and I have seen it for $12/lb. I think Tin has also gotten expensive so maybe that is why. 
Robert


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## rwm (May 16, 2021)

It was such a nice day here I decided to cast something.




They look pretty good. Minor porosity in non-critical areas. These are machined square but are oversize. The bore is 1.450 and the OD is about 3.7". One is .800 thick and the other a little thinner. Man these are heavy.

Robert


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## Flyinfool (May 16, 2021)

Sure looks purdy.


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## Flyinfool (May 18, 2021)

At the moment as far as I know we have 7 people committed and one uncommitted in this project.

@Shotgun
@Flyinfool
@ttabbal
@Ianagos
@ErichKeane
@erikmannie
@Brento

and @rwm as uncommitted

I have attached the latest BOM so everyone can see what is left to do.
SEE BELOW


----------



## Brento (May 18, 2021)

I did a little research on the taper endmill i had and it was unfortunately a 1/4" and not 3/16"


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## rwm (May 18, 2021)

There are a lot of parts to this. If yall want me in I will cast the blanks (assuming they machine OK) and pick up some of the smaller parts. I am out of brass so I will need to buy materials for alloy. It looks like the gear shift assembly needs an owner for starters.
Robert


----------



## Flyinfool (May 19, 2021)

Here is the new latest and greatest BOM. I believe it is now correct with all the names on parts.


----------



## Shotgun (May 19, 2021)

@Flyinfool , could I ask you to either consolidate all of the "bought parts" into one list, or share the spreadsheet with me so that I can.  I'd like to see if I can get an order together from AliExpress.


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## ttabbal (May 19, 2021)

It probably makes sense for me to do the pair of "DH 009 Main Base End Cap". They need to match up with the trunion anyway, and would use the same stock. 

If someone else was really excited to make them, I can send them some stock.


----------



## ttabbal (May 19, 2021)

So, order of operations for the trunion, just to see if someone has an easier way to do it. 

Cut an over length part on the bandsaw, with some extra for holding in the chuck, so I can do all diameters in one setup. Then face the end and turn OD with the steps. Bandsaw off holding stock, flip in the chuck and face the other end square. Or perhaps square it on the mill with the part in a vee block. Probably saves indicating it on the lathe. 

On the mill, hold in the vise with the faced ends on the jaws. Mill one flat (center drawing), flip and use parallels against the flat to do the opposite side. Use the same setup to get the two flats with a radius (seen on the left/right drawings). Bore the bearing hole, drill/tap the holes. Rotate 90 degrees using parallels on the flats and cut the slot. Probably drill out, then clean up with an endmill. 

Hold vertical in the vise with blocks on the flats, drill/tap the bolt circle in the ends. 

Switch to rotary table, drill/mill the tapered holes. Mark lines with a 90 degree end mill. Stamp the numbers. I might need to work up a jig to line them up nicely. 

Probably some deburring in there.. and a lot at the end. 

Material is hot rolled, suspected 4140. I can use a forge to release stresses before machining if needed. Do we think it will be? I guess if it's not, all I'm out is a little propane and time.


----------



## Shotgun (May 19, 2021)

You could save quite a bit of stock if you could turn the OD and shoulders on several at once and then bandsaw them apart.
Hot rolled doesn't have as much stress.  Right?


----------



## Flyinfool (May 19, 2021)

Shotgun said:


> @Flyinfool , could I ask you to either consolidate all of the "bought parts" into one list, or share the spreadsheet with me so that I can.  I'd like to see if I can get an order together from AliExpress.


----------



## ttabbal (May 19, 2021)

Shotgun said:


> You could save quite a bit of stock if you could turn the OD and shoulders on several at once and then bandsaw them apart.
> Hot rolled doesn't have as much stress.  Right?



Good point. I should be able to fit a couple of them on the lathe at a time at least. It's a PM1127, and the part is about 6" long, so perhaps 3 at a time, depending.. 

I have read that stress isn't as big an issue on hot formed material, but I'm unsure how much difference it makes.


----------



## Shotgun (May 19, 2021)

ttabbal said:


> Good point. I should be able to fit a couple of them on the lathe at a time at least. It's a PM1127, and the part is about 6" long, so perhaps 3 at a time, depending..
> 
> I have read that stress isn't as big an issue on hot formed material, but I'm unsure how much difference it makes.


I'd put the hot-rolled material I had in the furnace, if I had the furnace up and running.  Just because.


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## rwm (May 19, 2021)

Do you guys want to put me in for the gearshift and whatever small parts are needed later? 
Robert


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## erikmannie (May 19, 2021)

rwm said:


> Do you guys want to put me in for the gearshift and whatever small parts are needed later?
> Robert



I vote Yes on the above.


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## Flyinfool (May 20, 2021)

I vote yes also.
That makes it an even 8 sets of parts that each person has to make.
Note that there are a few parts that require more than 1 part per dividing head. So those will require 16 or 18 parts to be made. Those parts have notes on the drawings.

I also believe that at this point this project should be closed to additional members so that once material is purchased no one has to run out to find material or redo setups or special fixtures, for one more part.

Of course there are still parts not spoken for, most of them are smaller not real difficult parts that can be picked up as we find out how things are going with what we have already signed up for. If anyone wants to take on additional parts just let me know and I will update and post the new BOM.

OK here is what I believe to be the final iteration of the drawings. I still have a little to do on the 4 assembly drawings but that will not affect the parts.

If anyone has any questions on how to do something just ask, I do think about order of operations while designing a part to be sure that it is possible to make it.

If everyone is in agreement, with this final set of info then I think we can wave the green flag and GO.

Since this thread is quite long already and is all about the design process and logistics so far do we want to start a fresh thread for all the build info?


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## Shotgun (May 20, 2021)

I don't know that another thread will do anything more than giving us multiple places to look for information.

Now, TIME TO MAKE CHIPS!!

BTW, I'm working on the "purchased parts" spreadsheet, with a mind to cutting costs.  For many of these, McMaster's has us buying a box of 100 so we can have 8 pieces. I'm looking at some of the "assortment" collections.  'Cause, if I'm going to spend $25, I'd at least like to have more than 90 screws of one specific size.  However, to accomplish this, we may need to deviate from the plans a bit.  I'll need to get with @Flyinfool to discuss each on an individual basis.

Example:  The roll pin called out is .125x.687, and you have to buy 250 for $12.  We need eight.  Harbor Freight has an assortment with ten that are .125x.625.  If the .060" doesn't make a difference, then it is nice to have an assortment on the shelf.


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## ttabbal (May 20, 2021)

Looks good to me. I'll get tools fired up.


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## Flyinfool (May 20, 2021)

There is nothing golden about the McMaster parts, I am using that to fully define the parts needed as McM gives fairly complete and accurate information on the part needed in that spot. There are many things that can be "adjusted" in size to accommodate a source.


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## Shotgun (May 20, 2021)

I think this is interesting enough to share.  It feels like I'm back at GE doing a "cost-out", where accountants went to work on a product after it was designed and tested to figure out a way to make it cheaper.

The biggest cost by far is the bushing.  @ttabbal , you said you might be able to make that.  How do you think that is looking?

The the Sector Springs.  I don't think we're going to get out of that one.

The Lever Handles, though.  Do we really need it to be 2.5" long?  I have some 1/4" cap screws.  1.5" shank, and then an 1" of thread. I could round the heads into a ball.  What say ye?

I've got the roll pins, if you .625 length is ok, and you guys don't mind HF roll pins.

I'm currently looking for screw assortments to see if I can get the different sizes in one pack.


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## Shotgun (May 20, 2021)

If we could use shorter 1/4x20 set screws, all we need could be covered by:









						Set Screw Assortment, 150 Piece
					

Amazing deals on this 150 Piece Set Screw Assortment at Harbor Freight. Quality tools & low prices.




					www.harborfreight.com


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## Flyinfool (May 20, 2021)

Shotgun said:


> I think this is interesting enough to share.  It feels like I'm back at GE doing a "cost-out", where accountants went to work on a product after it was designed and tested to figure out a way to make it cheaper.
> 
> The biggest cost by far is the bushing.  @ttabbal , you said you might be able to make that.  How do you think that is looking?
> 
> ...


Yes the bushings could be made of brass, bronze, oilite or ???? It would be a bit less to make them from McMaster P/N 8911K312 Bronze Tube. Or similar.

The lever handle could easily be be made, I was trying to reduce the number of made parts since all were not signed up for already. Could be a good excuse for someone that wants to make a ball turner for their lathe.

.625 HF roll pins would be fine.



Shotgun said:


> If we could use shorter 1/4x20 set screws, all we need could be covered by:
> 
> 
> 
> ...



We could uses the 3/8 in the gear and the 1/4 long in the Quick index, that would allow that kit to work.

Due to the low quantities of a lot of the hardware, it may be even cheaper to get the exact qty needed from the local hardware store.


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## ttabbal (May 20, 2021)

I think the bushing looks easy enough to make from tubing. With prices for brass/bronze, I'm not sure it's much cheaper that way though. We could certainty look into it. We might be able to find suitable material on ebay or similar. I believe the McMaster part is oilite.


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## Flyinfool (May 20, 2021)

True the McM part is oilite, but this not high speed or even will make a real lot of revolutions in its lifetime. I think brass or bronze will still out live most of us. I would think that this spindle in real terms will never make 1,000 revoultions in its lifetime, for most of us not even 100.


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## Shotgun (May 20, 2021)

I made a ball turner rig out of a boring head, but haven't had a call to use it yet.  If people are ok with either a shorter lever, or some thread showing, I'd like to give that one a go.

This is going well.  I like having the assortment kits, 'cause I hate being into a quick project, and then having to spend 45min running to the store for a $0.09 screw. 

Here's the update spreadsheet.


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## Flyinfool (May 20, 2021)

ttabbal said:


> Good point. I should be able to fit a couple of them on the lathe at a time at least. It's a PM1127, and the part is about 6" long, so perhaps 3 at a time, depending..
> 
> I have read that stress isn't as big an issue on hot formed material, but I'm unsure how much difference it makes.


There would also be no issue with leaving centers in one or both ends of the trunion.
That way you could have a longer bar sticking out of the chuck and still support the end properly.


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## Brento (May 20, 2021)

I know if i was gonna buy the hardware for my set i was going to buy most that i can from a local hardware store be it tractor supply lowes or HD


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## Brento (May 20, 2021)

What are we thinking to do with the hardware?


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## Shotgun (May 20, 2021)

Would it be fair to ask each person to arrange for the hardware to complete their part?  I know there will be several situation where "my part" is a bit nebulous.

Alternatively, I could volunteer to buy the hardware with a little help from my friends. 

Which is a good segue in to another point.  I think the clamp guys had a good idea with shipping that maximized the "if it fits, it ships" rates.  Most of you should be able to fit all 7 of the sets you're making into one box.  @ttabal and myself have the large, heavy parts, so that really wouldn't be a thing.  I suggest that we each ship a part to @Flyinfool for assembly and testing, and then most of you make up a single box with six parts to mail to either @ttabbal or myself.  @ttabbal  and I will then be responsible for shipping a kit box to each of you.

So, if I were to get all the hardware, it would be included with the box I sent out.


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## ErichKeane (May 20, 2021)

Shotgun said:


> Would it be fair to ask each person to arrange for the hardware to complete their part?  I know there will be several situation where "my part" is a bit nebulous.
> 
> Alternatively, I could volunteer to buy the hardware with a little help from my friends.
> 
> ...


Was the idea for all of us to send all our parts to 1 person for assembly/QC? If that is the case, we are probably better off just having the parts ordered as a group.

I'd be fine putting a few bucks in to "group buy" that hardware.


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## Shotgun (May 20, 2021)

Flyinfool said:


> hink that this spindle in real terms will never make 1,000 revoultions in its lifetime, for most of us



Is there any reason this can't be an aluminum bearing?  Wear is not an issue.  Just smooth operation without galling.


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## ErichKeane (May 20, 2021)

Shotgun said:


> Is there any reason this can't be an aluminum bearing?  Wear is not an issue.  Just smooth operation without galling.


I was wondering about some sort of delrin or something? I think plastic solid bushings are pretty cheap.


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## Shotgun (May 20, 2021)

Looked at the cost of delrin bushings on McMaster-Carr and choked.

But, you can get a foot of aluminum of the correct ID/OD for less than $6









						6061T6 Round Aluminum Tubing | Aircraft Spruce
					

6061T6 Round Aluminum Tubing 6061T6 Round Aluminum Tubing




					www.aircraftspruce.com


----------



## Shotgun (May 20, 2021)

ErichKeane said:


> Was the idea for all of us to send all our parts to 1 person for assembly/QC? If that is the case, we are probably better off just having the parts ordered as a group.
> 
> I'd be fine putting a few bucks in to "group buy" that hardware.


 
Maybe not assembly.  More for distribution.  But, yeah, that was my thinking.  The logistics just work better.


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## rwm (May 20, 2021)

I would be afraid the aluminum would gall. Can we find cheaper oilite or delrin somewhere?
I was planning on making the shift lever as part of the gearshift assembly but I will defer this if someone else wants it.
Robert

Edit: I see acetal bar for $10 per foot for 1-3/4" OD. Could make bushings from that.
R


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## ErichKeane (May 20, 2021)

rwm said:


> I would be afraid the aluminum would gall. Can we find cheaper oilite or delrin somewhere?
> I was planning on making the shift lever as part of the gearshift assembly but I will defer this if someone else wants it.
> Robert
> 
> ...


Cheaper than I found  Amazon was $30/ft or so. But $20 for 2 feet (enough for the 16 we need) seems like a heck of a deal over the $6 each!


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## ttabbal (May 20, 2021)

Amazon.com: Acetal Copolymer Round Rod, Opaque Black, Standard Tolerance, 2" Diameter, 12" Length : Musical Instruments
					

Buy Acetal Copolymer Round Rod, Opaque Black, Standard Tolerance, 2" Diameter, 12" Length: Multipurpose - Amazon.com ✓ FREE DELIVERY possible on eligible purchases



					www.amazon.com
				




Could easily get 10 from a foot, 1" length bushings. 

You guys beat me to it.  I also went to 2", but I do think 1.75 would get the job done, with the bore in the trunnion adjusted.


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## ErichKeane (May 20, 2021)

ttabbal said:


> Amazon.com: Acetal Copolymer Round Rod, Opaque Black, Standard Tolerance, 2" Diameter, 12" Length : Musical Instruments
> 
> 
> Buy Acetal Copolymer Round Rod, Opaque Black, Standard Tolerance, 2" Diameter, 12" Length: Multipurpose - Amazon.com ✓ FREE DELIVERY possible on eligible purchases
> ...


I thought the originals were 1.6875 or something odd like that? I searched 1.75 to have room to turn the od


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## ttabbal (May 20, 2021)

ErichKeane said:


> I thought the originals were 1.6875 or something odd like that? I searched 1.75 to have room to turn the od



1.6895. I must have been thinking about something else.


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## rwm (May 20, 2021)

Here you go if someone knows how to turn thin bushing in acetal?








						Delrin - Acetal Plastic Rod 2" Diameter x 12" Length – Black  | eBay
					

Material: Delrin Acetal. Characteristics of Delrin - Acetal Plastic Rods are Shaped: Rod. Wide end use temperature range. Colour: Black. Image displayed is for illustrative purpose only.



					www.ebay.com
				



R


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## Ianagos (May 20, 2021)

How about uhmw?

I have a bunch of 2” diameter I can cut all the bushings pretty easy on the cnc?


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## rwm (May 20, 2021)

These bronze bushing would yield all bushings for us:








						Brass Bushing 1-1/2" Bore, 2" OD, 3-1/4" Length Lot of 4  | eBay
					

, Oil Threaded--New Surplus--Not In Box--4/21JS.



					www.ebay.com
				











						Brass Bushing 2" OD 1 1/2" Bore Assorted Lot of 5  | eBay
					

1-1/2" Bore, 2" OD--3 Bushings are 3" Long, the other 2 are 4" Long--New Surplus--Not In Box--4/21JS.



					www.ebay.com
				




This seller has a lot of 1-1/2 ID bushings. It would not be hard to cut these into 16 individual bushings as long as the ID is not oversize.
R


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## Brento (May 20, 2021)

Were we still sending one completed part out in the beginning to do a QC? If so then i may end up holding everyone up. I know most of my parts all make up one single assembly so porb not alot of QC to check on that.

I am also fine with either buying my own hardware or doing a group thing.


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## Brento (May 20, 2021)

Question for the group. I dont know my grades for materials. I have some brass but i am not sure how soft it is. Is 360 brass soft enough?  I am looking for the brass to do the brass plugs.


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## ttabbal (May 21, 2021)

Well, I decided to try stress relief. My forge is a bit shorter than I thought, I could only get about 14" of stock in the chamber. 

Heated up nicely, about cherry red and held it for a while. Didn't think to grab a timer, probably about 30min. Shut down the gas and covered the opening with fire bricks. It will likely be cool in the morning. Hopefully it helps. If nothing else, it's kind of interesting to get that big chunk of steel that hot. I've only ever done small parts before.


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## Shotgun (May 21, 2021)

ttabbal said:


> Well, I decided to try stress relief. My forge is a bit shorter than I thought, I could only get about 14" of stock in the chamber.
> 
> Heated up nicely, about cherry red and held it for a while. Didn't think to grab a timer, probably about 30min. Shut down the gas and covered the opening with fire bricks. It will likely be cool in the morning. Hopefully it helps. If nothing else, it's kind of interesting to get that big chunk of steel that hot. I've only ever done small parts before.


Get a picture next time please.  Huge chunks of metal heated cherry red makes me giggle like a little girl.


----------



## ErichKeane (May 21, 2021)

Brento said:


> Were we still sending one completed part out in the beginning to do a QC? If so then i may end up holding everyone up. I know most of my parts all make up one single assembly so porb not alot of QC to check on that.
> 
> I am also fine with either buying my own hardware or doing a group thing.


I didn't think that was going to be a thing unless you wanted to?  I presume we might end up with a couple of re-makes along the way or some sort of problem-solving to work around issues with design/manufacture, but I would think it is pretty much a waste to ship a set of parts a 2nd time.

IMO, it would break up my manufacturing process.  Since I'm making 8 of my thing, I'm likely going to use the same setup and do 1 operation at a time on each piece.  If I was needing to do 1 whole one, then wait, then re-setup my fixtures (particularly the hobbing and external cut, both of which are needing a turned setup) it would be a pretty big interference with my process.


----------



## rwm (May 21, 2021)

I think we should build one of these, assemble and test it and then re-asses. We can then proceed with a production line process for the next 7. I know it is not efficient to ship one assembly but it could save you a lot of time, expense and material if it uncovers a problem that we did not foresee. 
I am sure we will want to make some improvements after the first one.
Robert


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## rwm (May 21, 2021)

Suggestion: Should we put the current drawings and documents on the first post for reference? (and keep them updated there)
Robert


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## Flyinfool (May 21, 2021)

Shotgun said:


> Would it be fair to ask each person to arrange for the hardware to complete their part?  I know there will be several situation where "my part" is a bit nebulous.
> 
> Alternatively, I could volunteer to buy the hardware with a little help from my friends.
> 
> ...


We are 8 members now.



rwm said:


> Here you go if someone knows how to turn thin bushing in acetal?
> 
> 
> 
> ...



I think that the delrin will be fine.
You turn the thin wall the same way you would turn a very small dia.
Turn the ID first.
Then turn the OD using a single pass to finish size.



Ianagos said:


> How about uhmw?
> 
> I have a bunch of 2” diameter I can cut all the bushings pretty easy on the cnc?



UHMW is a bit soft for this, the cutting forced when making a gear may deflect the UHMW.


----------



## Shotgun (May 21, 2021)

rwm said:


> Suggestion: Should we put the current drawings and documents on the first post for reference? (and keep them updated there)
> Robert


Done.
I'll do my best to keep them up to date.


----------



## Shotgun (May 21, 2021)

Flyinfool said:


> We are 8 members now.


But if you've shipped one for QC, and you don't ship one to yourself, that leaves 6 to ship to others.


----------



## ttabbal (May 21, 2021)

I don't think it makes much difference for me to make one for QC vs make all of them. The setups for the trunnion aren't too complex so I should be fine.


----------



## ErichKeane (May 21, 2021)

Ok, started getting my materials together! For the worm wheels, I have this hunk of aluminum that is .775 thick, 11.25x12". I should be able to get 9 wheels out of this. Additionally @rwm cast that gorgeous brass one that I will make as well!  




Additionally (rhs of screen) I have 5 12"*1 1/16" 12L14 chunks for the worm gear shaft. Plus 1 more hunk of 1.5" in case it gets really bad!

Here the aluminum is blued up (and drying while I post this!) So I can mark it and chop it up somehow. Hopefully my woodworking bandsaw doesn't complain too much, I don't think I can afford a circular saw blade's kerf!


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## Flyinfool (May 21, 2021)

When you cut out the blanks from that chunk of AL, are you planning to cut squares or circles?
I was thinking to use a Ø3.75 hole saw to cut the blanks. You will have to measure the saw to be sure there will be enough material left on the OD of the puck, it will be close. This will also give a center hole to start from.


----------



## ErichKeane (May 21, 2021)

Flyinfool said:


> When you cut out the blanks from that chunk of AL, are you planning to cut squares or circles?
> I was thinking to use a Ø3.75 hole saw to cut the blanks. You will have to measure the saw to be sure there will be enough material left on the OD of the puck, it will be close. This will also give a center hole to start from.


Actually most of the way to cutting them to squares  just finished cutting long way to get 3 strips, then put a couple of pieces through my bandsaw to cut them down the other way.

Nearly done!

I didn't really want to buy the hole saw, plus always end up messing them up  though if I had a tough time fitting them all (and had to tessalate) I probably would have invested.


----------



## ErichKeane (May 21, 2021)

And chopped up  I had plenty of room in 1 dimension, so I used the circular saw first. That long edge is about 4" on all(or a touch less).




Next I set them up in the horizontal bandsaw and let that go to work, which did a surprisingly good job! Those dimensions are all right about 3.7 or so, at least 1 is a touch smaller.  I think it'll be alright, since I need to be at 3.600.

I found the centers using the diagonal method which I'll use to set these up in the 4 jaw. I figure I'll cut the centers, then make an arbor to hold them centered while I cut the outside to size. I haven't decided yet if I'm going to cut the center too small do my arbor can have a key to keep them from spinning (then come back to cut the center to full size!), else I was just thinking super glue. 

Too bad this wasn't designed with a woodruff key, it would make my decision way easier


----------



## Brento (May 21, 2021)

i have most of my material on hand need to order some aluminum and some softer brass and a new boring bar and i should be ready to start at it. After i finish and hone a few special made tools for the jobs. Honing some of the radius cutters isnt gonna be pretty lol


----------



## Shotgun (May 21, 2021)

ErichKeane said:


> I found the centers using the diagonal method which I'll use to set these up in the 4 jaw. I figure I'll cut the centers, then make an arbor to hold them centered while I cut the outside to size. I haven't decided yet if I'm going to cut the center too small do my arbor can have a key to keep them from spinning (then come back to cut the center to full size!), else I was just thinking super glue.
> 
> Too bad this wasn't designed with a woodruff key, it would make my decision way easier



You could start by drilling and tapping for the set screw and put a channel on your arbor.


----------



## Shotgun (May 21, 2021)

I'm finishing up the angle block I started with a piece of the angle that was cut to short for our project.  It has been good practice.

What do you do when you haven't made yourself any machinist jacks yet?


----------



## ErichKeane (May 21, 2021)

Shotgun said:


> You could start by drilling and tapping for the set screw and put a channel on your arbor.


I thought about that, but I couldn't think of a way to ensure that the set-screw ended up between two teeth that way.


----------



## Shotgun (May 21, 2021)

I had to provide a "starter cut" for the hob.  Make the first starter cut go right through the middle of the screw hole and you're golden.


----------



## ErichKeane (May 21, 2021)

Not sure what you mean by a starter cut, but I sorta have an idea?

It is a pretty deep tapped hole as well, and 10-32! Luckily it's aluminum otherwise I'd break half of my tries 

Also, flyingfool: the driven gear seems to have lost its center hole dimension. It's 1.500, right? I went to look for tolerance and didn't see it.


----------



## erikmannie (May 21, 2021)

Today I received an 8” length of 2-1/4” 12L14 for the first spindle. I am sure that I will knock it out this weekend. I will take plenty of pictures of the action.

I just bought 3 more of the same on eBay for $59.44 delivered. These come from Oakland Steel in Sterling Heights, MI.

I can make 2 spindles next weekend because of the Monday holiday.




I am following this drawing:


----------



## Flyinfool (May 21, 2021)

ErichKeane said:


> Not sure what you mean by a starter cut, but I sorta have an idea?
> 
> It is a pretty deep tapped hole as well, and 10-32! Luckily it's aluminum otherwise I'd break half of my tries
> 
> Also, flyingfool: the driven gear seems to have lost its center hole dimension. It's 1.500, right? I went to look for tolerance and didn't see it.



Yes there are a few scattered dimensions that seem to have disappeared when the file crashed.
Just let me know when you find them and I will fix it.

When you drill and tap the setscrew hole, It is acceptable to drill a clearance for the shank of your tap as long as you keep 3/8 inch of thread at the bore. That will make tapping a LOT easier.


----------



## Flyinfool (May 22, 2021)

rwm said:


> Suggestion: Should we put the current drawings and documents on the first post for reference? (and keep them updated there)
> Robert





Shotgun said:


> Done.
> I'll do my best to keep them up to date.



I had been thinking about that too.
I was wondering if I should go thru and delete all of the iterations of the design process so that there is only one correct version in the thread and no incorrect versions.
But on the other hand, leaving all the old info for future people that may view this thread it will show the iterations and evolution of the design process.

I believe I always had the do not use disclaimer in the early file post.


----------



## rwm (May 22, 2021)

You could change the names of the old files to read "old version" or something like that.
This thread is going to get so long and complex I fear we are all going to start missing important comments! At some point we may need to rely on PM threads to work out problems and then just post the solutions here. Jeff may get buried in PM's!
R


----------



## ErichKeane (May 22, 2021)

rwm said:


> You could change the names of the old files to read "old version" or something like that.
> This thread is going to get so long and complex I fear we are all going to start missing important comments! At some point we may need to rely on PM threads to work out problems and then just post the solutions here. Jeff may get buried in PM's!
> R


This is why I had suggested separate build threads at one point. Even if we don't want to do that, we should close this one and start a new one for the build process.


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## Flyinfool (May 22, 2021)

If we want to keep this as the design thread, including for design changes not yet thought of and start a new build thread, I can start it, that way I can keep the files in the first post as the latest version. It will make it easy to keep up with changes. And there will be changes. This thread is already pretty long with 450 posts and 45 pages, and it even did pretty good at not getting hijacked anywhere along the way.
I think with the number of parts to make, to have a separate build thread for each part or even each person will be too spread out over time and someone trying to duplicate this in the future will have a hard time finding all the pieces. A link to the build thread can be put in post #1 here and a link to this thread can be put in the build thread.


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## erikmannie (May 22, 2021)

I am making the spindles. How many spindles should I make?

I just ordered two 1-1/2” X 12 nuts and a Shars 1-2” screw thread micrometer because I am going to single point the threads.

As such, I won’t be able to start work on the spindles until next weekend.





__





						1-2" Screw Thread Micrometer
					

Shars Tool




					www.shars.com
				







Edit: After I bought the screw thread mic, I realized that I could have used my (PeeDee type) thread wires. I could have also used a nut (not the best choice). That’s okay, though, because I love micrometers.


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## Shotgun (May 22, 2021)

@Flyinfool , you start the build thread, and I'll edit my first post to link to it.


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## Brento (May 22, 2021)

erikmannie said:


> I am making the spindles. How many spindles should I make?
> 
> I just ordered two 1-1/2” X 12 nuts and a Shars 1-2” screw thread micrometer because I am going to single point the threads.
> 
> ...


I believe there are 8 participants so 8 spindles.


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## Flyinfool (May 22, 2021)

OK Here is the start link to the build thread.








						Group Project: Dividing Head - The Build
					

This will be the build thread for the group built Dividing head we will all be posting notes, pics, vids? of our progress, there can also be discussion about setups or how to do some things, order of operations or anything else that comes up pertaining to making the parts. The original thread...




					www.hobby-machinist.com


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## erikmannie (Jun 5, 2021)

I’m still working on the first spindle. This is as far as I got before I had to leave for work:


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## rwm (Jun 5, 2021)

I think you meant to post this in the other thread? Nice though! What is the insert you are using? Are you happy with the finish?
Robert


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## erikmannie (Jun 5, 2021)

Yes, I meant to post this in the other thread.

This is a medium insert from Carbide Depot. The nose radius is 1/32”. I am not quite happy with the finish.

The smaller diameter is not done yet.


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## rwm (Jun 5, 2021)

Well I could use some guidance on inserts for 12L14 if you figure it out. My surface finish has not been excellent either
R


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## Shotgun (Jun 26, 2021)

It's late in the game for a design tweek, but I think this one might be warranted.

When I make the Trunnion Crank arm, I'm going to cut the big hole out with a hole saw.  That will leave a big round of 3/4" steel that is ALMOST big enough to serve as the trunnion end cap.  Given a 3" saw and a 1/8" kerf, that'll leave 2.75" round.

If we adjust the shoulder of the trunnion, that round would be big enough.  Plus, it would be wide enough to put our angle markings on the outside where they would be more visible.


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## Flyinfool (Jun 26, 2021)

3/4 is kind of thick for the caps, especially on the crank side. How good are you at parting or slitting to split that slug in half to make both caps out of it? 

If the degree marking is to move to the cap, then there will need to be 2 non symmetric dowel pin holes to make lining it up repeatable. as the cap is loosened and tightened in normal use.

Of course it will also matter if @ttabbal has already got that far on the trunion.


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## Shotgun (Jun 26, 2021)

Some slight confusion.  The material would come from the crank, but would be used as the cap. . . on the opposite side.

You are correct that alignment would be the issue, however.  I think smoothly fitting screws would be enough accuracy, but that would radically increase the difficulty of the part.


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## Flyinfool (Jun 26, 2021)

It would also have a big impact on the location accuracy of the mounting holes in the trunion.


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## Ianagos (Jun 27, 2021)

rwm said:


> Well I could use some guidance on inserts for 12L14 if you figure it out. My surface finish has not been excellent either
> R



12l14 is gummy if run as high sfm as you can. I have some cermet inserts that finish well but you need to get up over 500sfm .002” per rev .02” doc that should do it fine. Small nose radius on carbide inserts work better for finishing but you need to still take a doc greater than the nose radius of the tool.


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## Ianagos (Jun 27, 2021)

I forgot to mention I’m still looking for material to make the index plates from. I had some large diameter steel rounds but turns out the were about 4.5” not Atleast 5 we need.

If anybody has a source let me know.

Going to try to start the trunions tomorrow. Once I knock out one the rest will go quick


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## erikmannie (Jun 27, 2021)

Ianagos said:


> I forgot to mention I’m still looking for material to make the index plates from. I had some large diameter steel rounds but turns out the were about 4.5” not Atleast 5 we need.
> 
> If anybody has a source let me know.
> 
> Going to try to start the trunions tomorrow. Once I knock out one the rest will go quick



I have always found what I needed on eBay. The metal comes in a flat rate box, so the shipping is not expensive.

You will be buying cutoffs, so I don’t think you’ll spend too much money.

Example:


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## Ianagos (Jun 27, 2021)

erikmannie said:


> I have always found what I needed on eBay. The metal comes in a flat rate box, so the shipping is not expensive.
> 
> You will be buying cutoffs, so I don’t think you’ll spend too much money.
> 
> ...



I’ve found it for about $7 a piece but I need 16 parts so it adds up a bit but I’ll keep looking.


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## rwm (Jun 27, 2021)

This guy can do custom cut circles at reasonable pricing. If we start with 1/4" plate and then machine it thinner (.200?) that should be fine.






						Security Measure
					






					www.ebay.com
				




Here's 20 pcs








						[20 pcs.] 1/4" x 5" Steel Disc (A36 Steel, Mild)  | eBay
					

Find many great new & used options and get the best deals for [20 pcs.] 1/4" x 5" Steel Disc (A36 Steel, Mild) at the best online prices at eBay! Free shipping for many products!



					www.ebay.com
				




Robert


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## Flyinfool (Jun 27, 2021)

a different tact.
A 1' x 4' plate of .25 thick A36 will work out to around 5.75 each, But you will need a 5.25 hole saw to chop out the blanks. Or you could band saw the blanks out of the sheet and then make them round in the lathe or mill.


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## Flyinfool (Jun 27, 2021)

That 20 pieces is an even better price and you get some left overs.


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## Ianagos (Jun 27, 2021)

Hoping also when I hold the plates if they will warp? Depends how I hold them I guess. I want to try to find something 3/8 thick and 5.12” in diameter so I can hold the part and turn and face it. Then flip it and do the finish facing and drilling.

Another thought I had was to have the plates ground flat and then use the mill to put the holes in it rather than the lathe.

Not decided yet


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## ErichKeane (Jun 27, 2021)

Ianagos said:


> Hoping also when I hold the plates if they will warp? Depends how I hold them I guess. I want to try to find something 3/8 thick and 5.12” in diameter so I can hold the part and turn and face it. Then flip it and do the finish facing and drilling.
> 
> Another thought I had was to have the plates ground flat and then use the mill to put the holes in it rather than the lathe.
> 
> Not decided yet


Too bad you don't have a cheap mag-chuck.  You could magnet it down and mill from there.


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## Ianagos (Jun 27, 2021)

ErichKeane said:


> Too bad you don't have a cheap mag-chuck. You could magnet it down and mill from there.



If the plates were ground flat a method I’ve used before is super glue.

I have a mag Chuck and a surface grinder just not setup well right now.


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## Weldingrod1 (Jun 28, 2021)

Why dont you get them plasma cut? You can get an undersize hole punched in the middle too!

Sent from my SM-G892A using Tapatalk


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## ErichKeane (Sep 9, 2021)

A little more progress today! Need about two hours to finish up these last 4! The finish on the one with the scar is rough... For some reason the 12L14 at the end got super gummy on that one. Other half machined easy...


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## ErichKeane (Sep 9, 2021)

ErichKeane said:


> A little more progress today! Need about two hours to finish up these last 4! The finish on the one with the scar is rough... For some reason the 12L14 at the end got super gummy on that one. Other half machined easy...


Ended up finishing them this afternoon! I might have to go back and recut the 3/8-24 thread, the die I was using didn't get to the shoulder (and doesn't seem very deep!). Otherwise, 1 part done!


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## ErichKeane (Sep 10, 2021)

A bit of work on my first driven gear. I cheated and am using my dividing head 

I shimmed the front of it up to get a roughly 5 degree angle on the pre-cuts hoping that would help.  I indicated the first wheel in an older jig, and setup to cut. 




About 30 mins of thinking, and I convinced myself it was right-enough to give it a shot. No Z axis on my DRO, so a height gauge and math came to my rescue.  I started my 3/64 -.075 deep first cut, then disaster!  Broke my wheel. No real idea what happened, it was cutting fine, then two wobbles and a split:





My backup cutter is a .078 thick smaller diameter, so I ran that instead and it worked fine (so far!).






Next I am probably going to take down this setup to do an attempt at hobbing. The setup is easy enough to do, and I want to use the same dividing head + bar for hobbing. I'd rather figure out I screwed up the first step after 1 instead of 11


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## Shotgun (Sep 10, 2021)

How old is that blade?  The little grayish area just under the 2 looks suspiciously like metal fatigue, right in a stress riser where a crack could get started.


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## ErichKeane (Sep 10, 2021)

I have no idea  I got it when buying one of my kennedy boxes from a retired machinist. The it also looks like chinesium . I think I cut successfully with it before, though I could be mistaken.


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## ErichKeane (Sep 10, 2021)

Welp... Hobbing attempt #1 went poorly... It would grab and start turning the gear, but never "found" it's track. I think I probably should do a "wider" cut next time?  I have a 1/8" cutter that I was afraid was too big, but I could try that next...

With that cutter though, I probably don't want to go as deep, since that means it'll be more visible on the sides.

Thoughts from those with experience?


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## Shotgun (Sep 10, 2021)

Slow down.  Slow WAY down.

The first pass should barely make a good nick on the part, and the part should be turning freely.  You may have to help it around with a little pressure on the back side of the blank to insure the hobb teeth land in the grooves.  The hobb has to be turning slow for that.  30rpm or less. After that has gone around the blank a couple times, feed in only a few thousandths, and let that go around a few times.  Still helping the blank turn as necessary.  Once the grooves are well established (it goes around itself without help or losing track), you can crank in a 5 thou cut and also speed up the rpm.  Maybe go to 10 once the chamfer of the hobb teeth are well below the surface of the cut.

It's a lot like hand tapping in that the first few turns are the most important and establish the cut for all that follow.  Only after the grooves are well establish can you increase the depth of each cut, but you have to make sure those first cuts start straight.


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## ErichKeane (Sep 10, 2021)

Shotgun said:


> Slow down.  Slow WAY down.
> 
> The first pass should barely make a good nick on the part, and the part should be turning freely.  You may have to help it around with a little pressure on the back side of the blank to insure the hobb teeth land in the grooves.  The hobb has to be turning slow for that.  30rpm or less. After that has gone around the blank a couple times, feed in only a few thousandths, and let that go around a few times.  Still helping the blank turn as necessary.  Once the grooves are well established (it goes around itself without help or losing track), you can crank in a 5 thou cut and also speed up the rpm.  Maybe go to 10 once the chamfer of the hobb teeth are well below the surface of the cut.
> 
> It's a lot like hand tapping in that the first few turns are the most important and establish the cut for all that follow.  Only after the grooves are well establish can you increase the depth of each cut, but you have to make sure those first cuts start straight.


Good to know! Slowest speed I have though is 60rpm... I WAS doing that but wasnt helping it spin myself...


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