Large-ish bore dividing head

Ok- a Super Spacer is now on my wish list. For now though, I went with a Phase-II Spindex and a non-threaded Hardinge 5C collet. Seeing that the 6" Super Spacer has a 1.73" bore- I already regret my decision and should have saved up more $$$ for the Super Spacer. Never the less, the Spindex will be handy for the shop...
 
Never the less, the Spindex will be handy for the shop...

Yes you will always find use for one of those. Having more than one is not even a bad thing.
 
Can anyone recommend a dividing head that I can use a collet to pass through up to 1.250" rod through? I have no experience with dividing heads, and I don't quite understand how things mount to them. Saying that- I'd be ok with holding the work in a 3 jaw as well, but I still want to be able to pass through stock up to a 1.25"

One part of machining that I'm still finding shocking is just how much material is wasted in work holding. I'd like to try to reduce this by NOT needing to cut off my material twice (or three times- or more) longer than what I'll need for the part. If I ever get good enough to spring for the super fancy materials like timascus, mokume, or dimascus where a 12" bar can cost more than $1000, then this will be absolutely imperative. With that material, the part off along is literally $50 down the drain.

But even for now- my 12" long bar of 1" diameter tellurium copper set me back $50. I'd like to get ten $5 parts out of it rather than three $17 parts!
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For what it's worth- I'm aware of tailstocks for dividing heads. Perhaps I'm thinking about things wrong and using a chuck/tailstock is the correct answer to my question. The problem though is that for what I want to do, I think I will need to mount the dividing head at a 45 degree angle to either x or y axis because I want to mill some 45* slits equally spaced around the rod. For that reason, I figured that working near the dividing head chuck would be the only option rather than at the tailstock end.

[EDIT]- Oh, and it has to fit on my Millrite table which is 8" wide.
Have you tried cutting this slot ?
I don't think you are going to be able to do that
Unless you put the dividing head and tail stock
On the table of a milling machine with a table that will rotate . And gear drive the dividing head
It will need to be on a universal horizontal mill
 
No, I don't have the equipment yet, but unless I'm missing something, I don't see the issue. The spin indexer should be able to be toe clamped down to the mill table at any angle I want, no? This is no different than using a dividing/indexing/rotary head with the work parallel to the mill table, just that the work is at a 45* angle to the mill table. Why shouldn't that work?
 
No, I don't have the equipment yet, but unless I'm missing something, I don't see the issue. The spin indexer should be able to be toe clamped down to the mill table at any angle I want, no? This is no different than using a dividing/indexing/rotary head with the work parallel to the mill table, just that the work is at a 45* angle to the mill table. Why shouldn't that work?
You said you wanted to cut a slot around the stock on a 45 degree . Are you planing on feeding the table while you rotate the dividing head by hand .
I might be the one that don't see what you are trying to make. Are you trying to sit a helix or spiral
Around that part on a 45 degree
 
The indexing head will sit in the horizontal position on the mill table such that the work is parallel to the mill table. Typically the work would be trammed in so it is actually inline with the x axis. However I'm going to rotate it so that it's:
  1. Still parallel to the mill table
  2. Rotated 45 degrees along the z axis
I will then come in with a ball end mill moving the table only along the Y axis. This will cut a slot at a 45 degree angle to the work. I'll then index the work some undetermined increment and repeat. Think about a rope knurl, perhaps- or maybe something like a star knob/handle thing. Or perhaps even better is something like a helical gear, though I do NOT intend on rotating the index axis while milling. I am cutting straight slots.


Super duper crude- top is the rod I want to cut diagonal slots in, bottom is how I'd setup the indexing head on the mill table. The slots will be whatever my smallest ball end mill is- I think .125" or maybe if I'm lucky .0625" and will be no more than .100" deep. They will likely be something like .25" long at the most- probably much less than that.
FullSizeRender_zpsmavkv0w0.jpg


I'm making something similar to the copper ring on this top (which sadly- I literally just googled for a similar image to my idea and found almost exactly my idea. I swear this is the first time I've seen this image. Sigh...)
efcea686ee2b2761331b55c8b0be3995_zpslbcqmjrr.jpg
 
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The indexing head will sit in the horizontal position on the mill table such that the work is parallel to the mill table. Typically the work would be trammed in so it is actually inline with the x axis. However I'm going to rotate it so that it's:
  1. Still parallel to the mill table
  2. Rotated 45 degrees along the z axis
I will then come in with a ball end mill moving the table only along the Y axis. This will but a slot at a 45 degree angle to the work. I'll then index the work some undetermined increment and repeat. Think about a rope knurl, perhaps- or maybe something like a star knob/handle thing. Or perhaps even better is something like a helical gear, though I do NOT intend on rotating the index axis while milling. I am cutting straight slots.


Super duper crude- top is the rod I want to cut diagonal slots in, bottom is how I'd setup the indexing head on the mill table. The slots will be whatever my smallest ball end mill is- I think .125" or maybe if I'm lucky .0625" and will be no more than .100" deep. They will likely be something like .25" long at the most- probably much less than that.
FullSizeRender_zpsmavkv0w0.jpg


I'm making something similar to the copper ring on this top (which sadly- I literally just googled for a similar image to my idea and found almost exactly my idea. I swear this is the first time I've seen this image. Sigh...)
efcea686ee2b2761331b55c8b0be3995_zpslbcqmjrr.jpg
I think I see what you are trying to do .
I think your slots will feather out on both sides of the arc of the cylinder
 
Yes, that is intentional with my design. Until I figure out some other cool thing to do with slotting... It might look kinda cool for them to feather out like that. There might be better ways to accomplish what I'm trying to do, but the fact is- I don't have a clue what I'm doing and just going with a setup that made sense to me. I'm sure there's better ways...
 
Yes, that is intentional with my design. Until I figure out some other cool thing to do with slotting... It might look kinda cool for them to feather out like that. There might be better ways to accomplish what I'm trying to do, but the fact is- I don't have a clue what I'm doing and just going with a setup that made sense to me. I'm sure there's better ways...
No you are doing a good ornate design
I think it will look good it is going to be a lot of
Cuts but you are right it will look good
 
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