levelzero -
It was late last night as I was typing, so I didn't make myself clear. Sorry.
The threadmill (the first image) was what I used to make the 1"-8 thread on the chuck adapter (the second image).
It is actually the second threadmill I have made. I made the first one because my brother saw the Tormach and asked, "so have you made your left-hand nut and bolt yet?" Over the next several weeks I thought about it and decided that I'd learn more by making a threadmill than buying one. The end result was a left-hand 1/2"-20 aluminum bolt and twin stacked nuts for him, and more knowledge for me. Just to get his attention, the bolt head is also engraved with his email address. I didn't get a photo before I sent it to him.
I had to make a new threadmill for the chuck adapter because the first one would not cut deep enough for 1" threads (since it was for inside and outside milling of a 1/2" hole, I made it from 3/8" drill rod). The new one (from 1/2" rod) is a little too long to keep from flexing while cutting, and I didn't harden the whole shaft this time. I think I will harden it properly next time to help control flexure (and reduce the number of passes required to finish the job). They really are easy to make, so I don't have a problem with making a new one to fit the job every time.
Regards,
- Just Gary  |