Going to make some TTS Style holders (ALA Hoss)

[mrcodewiz]

I am going to attempt to make some TTS holders like Hoss did but I thought I would ask a couple questions before I get started. Just thinking in my head, this was my plan on how to actually make them:


1) Chuck up a piece of drill rod in my 3 jaw chuck on the lathe
2) Cut down the end of the piece which will be the .5" shaft that goes in the collet
3) Cut out the shoulder (part that indexes to the spindle)
4) Remove holder, flip around and stick the shaft in a .5" collet in the lathe
5) Cut down shaft, bore hole a little undersize for the end mill
6) ream end mill hole to size

Is there anything wrong with this plan? I would think using a collet to put the shaft in would make the hole for the end mill perfectly centered but I want to make sure everything is perfect and not out of round or anything.

-Kevin

[Enraged]

I think the TTS uses a 3/4" straight shank

[philbur]

I don't know what your mill spindle taper is but the TTS has a 3/4" shank. This is the largest diameter you can use with an R8 collet.

Phil

I am going to attempt to make some TTS holders like Hoss did but I thought I would ask a couple questions before I get started. Just thinking in my head, this was my plan on how to actually make them:


1) Chuck up a piece of drill rod in my 3 jaw chuck on the lathe
2) Cut down the end of the piece which will be the .5" shaft that goes in the collet
3) Cut out the shoulder (part that indexes to the spindle)
4) Remove holder, flip around and stick the shaft in a .5" collet in the lathe
5) Cut down shaft, bore hole a little undersize for the end mill
6) ream end mill hole to size

Is there anything wrong with this plan? I would think using a collet to put the shaft in would make the hole for the end mill perfectly centered but I want to make sure everything is perfect and not out of round or anything.

-Kevin

[bodysnatcher]

FYI you can get an R8 at 1 inch..i have one just fyi

[mrcodewiz]

Yes, you are both right. It is .75. I was going from memory which obviously is not very good. I have an R8 spindle on my X2. Other than my dimension on the shaft being wrong, does my process sound OK or would you do it a different way?

[MrWild]

I'd use a four jaw chuck as a three jaw just isn't precise enough. While doing the collet end, also do a skim cut on the OD. This will give you a reference that is aligned with your first operation when you flip the part. When you flip it, indicate both near the chuck and outward as sometimes you can have a wobble and while indicated .000 near the chuck, it can be out further out. Use a large enough diameter raw stock so you have a good mating surface with the spindle while also have a wide enough relief for the R8 to extend into during a tool change.

[philbur]

I was aware of this but I've never seen one. As the parallel section of the shank of an R8 collet is less than 1" the holding length on a 1" must be significantly shorter than normal unless the nose is extended beyond the taper, all of which would make the collet less rigid. I have always assumed that larger than 3/4" (20mm) although possible was only intended for special use where it was a "must have" regardless of limitations with respect to rigidity.

Just a thought
Phil

FYI you can get an R8 at 1 inch..i have one just fyi

[hoss2006]

7/8 R8 collets are commonly included in many sets, I have a few.
Anyone looking for a 1 inch can get them at MSDiscount.
Hoss

[hoss2006]

I am going to attempt to make some TTS holders like Hoss did but I thought I would ask a couple questions before I get started. Just thinking in my head, this was my plan on how to actually make them:


1) Chuck up a piece of drill rod in my 3 jaw chuck on the lathe
2) Cut down the end of the piece which will be the .5" shaft that goes in the collet
3) Cut out the shoulder (part that indexes to the spindle)
4) Remove holder, flip around and stick the shaft in a .5" collet in the lathe
5) Cut down shaft, bore hole a little undersize for the end mill
6) ream end mill hole to size

Is there anything wrong with this plan? I would think using a collet to put the shaft in would make the hole for the end mill perfectly centered but I want to make sure everything is perfect and not out of round or anything.

-Kevin

That's exactly how I did mine. You might need to check the runout of your collet chuck.
Could be a bad collet as well.
Hoss

[Andre' B]

If it were me I would change line 6 to.
Finish bore or maybe even grind with the holder in the milling machine spindle.

Lathe or mill I would not use a reamer.

[mrcodewiz]

What is wrong with reaming?

I have an old south bend so the collets go directly in my spindle. I will check the runout of the .75 collet though and see how good it is.

[hoss2006]

There is little to worry about reaming unless your tailstock is grossly misaligned, double check that.
A ream will be guided by the hole it is reaming.
I bored out the 3/4 toolholders I made, no ream that big.
I prefered the deadon diameter accuracy of the reamed hole
vs the boring bar blowing over .001.
Hoss