Group Project: Dividing Head - The Build

[rwm]

I fixed the attachment.
So far I plan to reduce the hole in the aux base to 2.00". Then I can reduce the perimeter of the aux base accordingly. Still torn about using a bronze bushing in the aux base. Probably not necessary but...

I'm thinking like this. Then there is no cutout at all.

 

[rwm]

I hope I finally have the Aux Base worked out:



I plan to have the trunnion tilt in the opposite direction of the plans so the cutout for the shifter is on the left. I found out that the hole in the base is not centered. I had to measure and correct. Fortunately I could bore .100" over on the aux base and get it centered to the other hole.

 

[rwm]

I got material for the trunnion and the spindle.

I'm thinking ahead to work holding. I am not sure how I want to configure the spindle. My lathe uses D1-3 mounting so that is out. I am considering:
Internal MT3 taper with draw bar. I have a small Bison chuck that mounts on an MT3 so that would be useful.
5C taper. I have 5C collets. I would need a larger through hole in the spindle I suppose.
ER32 taper. I would have to buy a set. I would thread the front for a nut.

Opinions?

 

[Flyinfool]

I have also not really thought about what or how to mount something on there.
My rotary table has a MT2 and I was thinking of getting a small MT2 chuck for that so there is one option similar to yours.
My lathe is also a D1-3 so I am not sure that can work. But my lathe also has a MT5 spindle with a MT5 to MT2 adapter so that would be another place for a MT2 chuck.
I was also consider a custom mounting plate for a 6 inch chuck on my RT I am not sure if I can design that plate to also be used with this dividing head???

 

[rwm]

I got the trunnion cylinder machined to size and hand fit to the base. It turns nicely with no slop. This ended up being way more complicated than I thought.
Now some sketchy work holding for the milling operations:

It should be OK since the jaws are 1.5" high and the cylinder is 3.000"
Order of ops?
My plan is to cut the flats where the spindle hole is, and then drill the spindle hole out to 1", then bore to final ID of 1.688.
Somehow I need to remove this to press in the bushings and then get it perfectly re-indexed to bore the bushings to 1.500. Formidable at best.
Then I need to rotate 90 deg and remove a metric $hit ton of material.
This is the component I have been dreading.
You got a better idea?

 

[rwm]

I just had an epiphany.
Instead of making a spindle for this, what if I buy an ER 32 collet holder with a 1.5" shank? I could thread the back end for the nut.

1.5"x6" ER32 STRAIGHT SHANK COLLET CHUCK EXTENSION HOLDER - buyustools

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www.buyustools.com

 

[Ianagos]

I got the trunnion cylinder machined to size and hand fit to the base. It turns nicely with no slop. This ended up being way more complicated than I thought.
Now some sketchy work holding for the milling operations:
View attachment 491565
It should be OK since the jaws are 1.5" high and the cylinder is 3.000"
Order of ops?
My plan is to cut the flats where the spindle hole is, and then drill the spindle hole out to 1", then bore to final ID of 1.688.
Somehow I need to remove this to press in the bushings and then get it perfectly re-indexed to bore the bushings to 1.500. Formidable at best.
Then I need to rotate 90 deg and remove a metric **** ton of material.
This is the component I have been dreading.
You got a better idea?

Yea when I starting getting this setup it was pretty challenging. I was trying to figure out the engraving when I got busy with life and I’ve been trying to get back to it since.

I have all the material for the trunion and diving plates sitting here and will ship to
Anyone who wants.

I wanted to drill the dividing plates and then surface grind them all but I haven’t gotten to
Setting that up…

I seriously apologize but I haven’t forgotten just things have gotten a bit difficult for me and I haven’t had much chance for hobby machining lately.. i hope to be back to it soon but like I said I have good material here for anybody that wants to take it on.

 

[rwm]

And....you can get an ER32 collet that goes up to 1". I did not know that.

Large ER32 Collet (7/8″ or 1″) - Cuttermasters

ER32 collet with expanded aperture to 7/8" or 1" Choose 7/8" (22.23mm) or 1" (25.4mm) from the dropdown menu

cuttermasters.com

 

[Flyinfool]

I forgot about ER collets. Since I currently do not have a collet system in my shop I can go to any one of them. I had once thought of getting getting either an ER32 or ER 40 for the lathe. Maybe this can help yank on the trigger a bit.

 

[rwm]

Jeff- Last you mentioned you did not have your shop set up. Do you have capabilities now?