Building an Atlas TH42 compound slide

[great white]

I already have a thread on my broken TH41 compound slide:

https://www.hobby-machinist.com/threads/aww-fudge-busted-my-th42-compound-slide.76225/#post-639127

I dealt with it by building a solid mount for my QCTP. I shoudl have built one for parting operations a long time ago anyways, so the broken top slide really just got me off my butt and forced the issue.

In that thread, Pierre has got me to the point that I am going to try and build my own compound slide. I plan to follow Pierre's lead on his top slide construction thread:

https://www.hobby-machinist.com/threads/replacement-compound-slide-for-atlas-10.708/page-2

I, however, do not have a mill. So I'm going to try and build one on my lathe using the Atlas milling attachment.

First is to buy some steel and a few cutters for my spring collet attachment (I mosty stick to 1/2 miling tools). I've got a few fluted end mills, but I'm looking at picking up a roughing cutter and a dovetail cutter.

The dovetail cutter I'm a little confused on. I've seen threads reference a 60 degree cutter for the dovetails, but I'm pretty sure last time I looked the dovetails are 45 degrees. Am I missing something here?

I'm not making a T-Slot, I'm going to drill and tap to mount my QCTP directly to the slide.

I will, however, be making more cross slides if I am successful at making this top slide. Mostly to widen the versatility of my Atlas with different mounting options for different tooling. So I'll need some T-Slot cutters eventually. What size woodruff cutter should I be looking for in order to make the T-Slots?

And I know this is going to make some (lots?) guys cringe, but I'm mostly limited to Ebay options. Both for price and availability. I'm just a guy in his garage turning single pieces out, so HSS is plenty good for me. The nearest place I would be able to find ANY machine tooling is Halifax, which is a 3 hr round trip. Even then, it's places like "busy bee tools", where I would be getting ebay quality stuff anyways, but I would be paying a premium price. Since I'm just a guy in his garage, I can wait the 4-6 weeks for the stuff to show up and not pay those premium prices. I know that sounds like justifying the use of ebay products (and maybe it is), but it's what I'm limited to. We all have our crosses to bear.

 

[T Bredehoft]

A Suggestion. When I built my 4 tool block, I made a replacement for the compound.
Under the compound, I found a circular dovetail. I put a cavity under my new plate, surrounded by three set screws that pushed pieces of 3/16 O1 drill rod, (chamfered to match the dovetail) on one end and hardened to hold the plate down. I put a block on the end to keep it alligned, but you could let it swivel if needed.

 

[pdentrem]

It is a 60 degree dovetail. It is common on almost all lathes and other equipment that I have seen to date. You will be taking light cuts and lots of them to cut the interior out. Once that part is done, the dovetail cutter will be a piece of cake.