VN High Speed Sub Head

The subhead will take the VN C collets but I need to make the key to hold the collets.

I’m waiting for the 13/16” spline shaft from McMaster to plug into an endmill collet holder instead of a one piece adapter shaft.
 
I too need to make that key. I do have that key in my VN 7 1/2 divider. Just have to dig it out for a pattern. I'll draw it up & post here when I do. McMaster carries that shaft. Good to know. What size & type of end mill collet holder does your no10 take? I just received C Type colts for the subhead! Not a full set, but a good start!

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Can anyone say what the through bolt on the side cover is for? I thought it was to lock the spindle vertically, but it isn't acting that way. Maybe the extra washer under the head (as received) is preventing it?

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EDIT: Never mind, brain fart. It does lock it vertically. I was checking rotation while tightening it. Sometimes I just have to laugh at myself.
 
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I will turn the one end of spline shaft to 3/4” to fit the 3/4” collet.

I have considered making the key from 3D printed stainles steel/bronze instead of trying to machine one. Likely will cost $30 per unit. Unless someone has extras laying around.

I also need a solution for the collet closer to securely hold collets in subhead. The version equipped with mine has too large of opening.
 

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There are two different collet drawings out there with slightly different versions of the keyway. This drawing summarizes them:
296947

Here's my design for the collet key, made by machining down a #608 Woodruff key:
296948

I have yet to make one and I don't have a real Van Norman "E-37½" key to check the finished depth. But people have used the above to make keys and so far have not indicated that it won't work. As far as the "tit" on the key goes, my plan is to make the key, insert it in the spindle with a collet, then use a transfer punch to mark the location of the dowel pin. The dowel pin hole is machined perpendicular to the flat, so it should be pretty straight forward.
 
There are two different collet drawings out there with slightly different versions of the keyway. This drawing summarizes them:
View attachment 296947

Here's my design for the collet key, made by machining down a #608 Woodruff key:
View attachment 296948

I have yet to make one and I don't have a real Van Norman "E-37½" key to check the finished depth. But people have used the above to make keys and so far have not indicated that it won't work. As far as the "tit" on the key goes, my plan is to make the key, insert it in the spindle with a collet, then use a transfer punch to mark the location of the dowel pin. The dowel pin hole is machined perpendicular to the flat, so it should be pretty straight forward.

I’m assuming from the second drawing the #608 key needs to be machined by 0.1691”?
 
Here's a better drawing that incorporates both of the source drawings:
296995

Woodruff keys have a little flat on the round side, parallel to the flat side. I think the best bet is to measure from the flat and machine the key down to about 0.21", which should be about 0.23" from the major flat. That should leave a little clearance to the bottom of the keyway. You don't want the key to bottom out in the keyway an keep the taper from seating.

It's been a long time since I looked at this. I don't know where I came up the the 0.016" number, the amount that the key extends into the ID of the spindle. I think the first drawing has the key intruding too far into the ID and will keep the collet/tool from entering the spindle. 0.016" may even be too much.

Let me know how this works out for you.
 
Cal has the solution for the key that we need Manderioli! The key in my divider is stuck & worn. Might have to make 2. Manderioli & I both have collet closures that don't hold regular "C" collets. I'm trying to come up with a 'washer' design that captures in the closure while centering on the collet & drawing it in as well. For now I am distracted by coming up with a collet extractor. Yup, stuck like chuck.

Does anyone have pics of what the 'C' collet closure looks like? What does the collet extractor look like?
 
Member Daryl (Uglydog) posted a PDF with parts diagrams for several sub-heads in this post: Vn Dividing Head Index Assembly - post #30

If you go to the third page, drawing 16-7740-A, the collet retaining caps are shown. I'm not sure why there are three different versions. One must be for "C" collets and a second is probably used with lug-driven tool holders. Unfortunately, my high-speed sub-head is without the retaining caps as well. I suspect that part 12-761-D, which appears to be a plunger sitting behind the tool, is what was used to eject tooling from the spindle via a drift applied from the rear of the spindle.
 
I thank you Cal. You always have good info & observation! If only those parts had a parts list with descriptions. Glad to have this much actually!

This is the head portion of that drawing - just to get a bigger pic out there.
07.jpg

What is beyond my experience is in seeing the (not 'C' type) retainers. What else fits that bore? 'C' type tool holders is best guess. This is why I wondered what the no10 mill itself uses for tool holders.
 
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