Group Project: Dividing Head - Organization and Design

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.

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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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
 
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.
 
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.
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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?
 
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?
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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.
 
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.
 
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.
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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
 
That should work. I'll need some room for cleanup on the diameter. But it looks like it will work.
 
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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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.
 
Shotgun said:
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.
Click to expand...

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