Mini T-Slot

[chiliviking]

I need to machine the T-slot for the tool post on my PM lathe project. I assumed I was going to use a woodruff key cutter for this however looking at the specs. on them even the smallest is 1/4" dia. Way too big. The slot for the tool post needs to be .188 x .070 and .156 at the skinny part of the T-slot. Obviously the .156 part is a straight forward milling job with common tooling but what is available to mill out the .188 X .070 part at the bottom. The length of the T-slot is approx. 5/8"

I have thought of some solutions but none that seem practical. Any ideas anyone?

 

[shred]

Grind down a 3/16" end-mill? I've heard of doing that, but never had to resort to it.

 

[Powder keg]

Would be easy with a surface grinder, or on the lathe with a toolpost grinder. On something this small, you could probably get buy with a dremel tool in a tool holder in the lathe. Chuck the endmill up and with a cut off blade in the dremel, grind the endmill down to the diameter and length you need. Run the lathe slow and the dremel fast for best results.

Wes

 

[mklotz]

Shred and Wes got there first but their suggested method is exactly how I did it when I made my lathe. Grind down a 3/16" endmill in the lathe using a Dremel mounted in the toolpost. Run the lathe backwards so the relative motion between end mill and grinding wheel is opposed.

Save this tool after you make it. The other PMR machine tool models have T-slots the same size.

 

[Bernd]

How about making your own cutter out of drill rod? Since the slide is aluminum you won't need to harden it and you learn tool making in the process. Just a thought which I'm sure you've contemplated.

Regards,
Bernd

 

[chiliviking]

Thanks so much to everyone for the help. The grinding down a 3/16 endmill was a very simple solution and worked great. This is a great BBS with lots of helpful folks.

I mounted my Dremel tool on my old South Bend, covered the ways with newspaper, filled a spray bottle with soluble oil and went at it.

It only took minutes to reduce the stem of a 3/16 endmill to below .156. Another cople qiuck passes with a .156 end mill followed by my new T-slot cutter and I was finished.

Gotta Love this Hobby!!

 

[BobWarfield]

That's looking like such a fun project Chili!

Best,

BW

 

[Powder keg]

Great Show!!! Thanks for the pictures:O) I might need to build one of those?

Wes

 

[Bernd]

Great job Chili. Just learned that grinding an end mill is faster than what I suggested. Will have to try that next time. BTW, I liked how you fastened that Dremel tool.

Bernd

 

[tel]

Same here - I've cut 'em with all sorts of odd things in the past, but that never occurred to me, got a lathe, got a Dremel, must 'ave a spare endmill somewhere