On 2013-03-24, RogerN wrote:
"Ignoramus3931" wrote in message
...

My guy asked me to cut a 1mm pitch thread on a custom shaft.

I could not do it on my lathe, so I finally bit the bullet and wrote a
subroutine to do threading with my 4th axis rotary table. I use a 60
degree chamfering end mill.

Now I can cut any thread, any pitch, right or left handed, and if the
thread is very coarse, the subroutine does it in several passes.

http://www.youtube.com/watch?v=JMENnIJrl9Y

I am afraid that it does not create a 100% correct thread geometry,
but I hope that I can do enough things with it to be useful with some
adjustments to diameter.

i

That's great!

I guess it would also work to make rifling guides, like 1 revolution in 9
inches or so?

Sure, it could not care less if the step is 1 revolition per 9 inch or
0.09 inch. It does the same thing. By default, it calculates depth
based on 60 degree thread profile, but you can specify your desired
depth.

i