Group Project: Dividing Head - Organization and Design

[Shotgun]

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.

 

[rwm]

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

 

[erikmannie]

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.

 

[Flyinfool]

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?

 

[Shotgun]

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.

 

[ttabbal]

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

 

[Flyinfool]

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.

 

[Shotgun]

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.

 

[Shotgun]

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

 

[Flyinfool]

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.

View attachment 366610

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.

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

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.