Ciambrone, Steve @ OS wrote:
gave me a threadingHi Steve. Thanks for responding. I've got a die holder for my lathe. And the holder works great. The problem is the dies (which I've gotten from Coles, McMaster Carr, etc - not junk) cut undersized/deformed threads (when new ! ! ). Even when shimming the die to maximum diameter. The die that I would use to cut the 3/32 - 48 thread I need cuts what looks like a buttressed thread with 67% space between the threads and 33% thread. HORRIBLE ! So to meet my standards, I've taken to cutting my own threads.
tool/die holder for a lathe.
I tried again last afternoon using the 29º compound offset, re-sharpening the bit, taking .0005 cuts, etc. Oh boy, I thought. This is working ! Within .0005 of final I checked with my standard tap cut female thread. Not quite. So I had to take one more pass. And it grabbed ! Now this was the full .325 threaded length (one plan was to cut 1/2 the length at a time to minimize stock sticking out of the collet - but this would require matching the thread pitch on rechucking - which I've done). So, I think that I can do it if I'm a little more careful, but I'm sure going to look into Harley Kelsey's suggestion of milling the threads. If I can find a 60º cutter (it would be pretty small), I'm going to try it.
later,
royce
