Single Point Threading on a PM-1030V?

[erikmannie]

My thread wires came out like the game pick up sticks, I remember it by the other name....

View attachment 314589

How annoying! Did you return them or fix the problem?

 

[erikmannie]

Maybe a little bit of the confusion comes from this? If you want to reduce your diameter, you dial in half of what you aim for in reduction. If you are reducing the radius, your math looks correct to me.

I fixed it.

I find it odd that my error was in the wording of the question. Thanks for finding the error and pointing it out.

 

[T Bredehoft]

Depth of cut....interesting. I've been chasing threads (cauaght a few) since 1971, never was concerned about how far to move the compound, (take a little at a time), but when the nut goes on, it's done.

 

[erikmannie]

Depth of cut....interesting. I've been chasing threads (cauaght a few) since 1971, never was concerned about how far to move the compound, (take a little at a time), but when the nut goes on, it's done.

Any tips on how to avoid overshooting the cut?

 

[T Bredehoft]

Slowly, slowly catachee monkey. Keep checking til it fits.

 

[Nigel123]

Also forgot to mention take some cuts not advancing the compound(read it somewhere)
It is surprising how much it cuts without advancing the cutter
Most times I check with a nut using caution near the finish to get a fit
If I cannot try the thread I use the .75 or .742 divided by the no of threads
I hit it right about 80 percent of time

 

[T Bredehoft]

On production work, I single point about 80% of the thread then run a die on. Comes out right every time.

 

[erikmannie]

On production work, I single point about 80% of the thread then run a die on. Comes out right every time.

I have never heard that. It sounds like a fantastic tip.

 

[erikmannie]

Also forgot to mention take some cuts not advancing the compound(read it somewhere)
It is surprising how much it cuts without advancing the cutter
Most times I check with a nut using caution near the finish to get a fit
If I cannot try the thread I use the .75 or .742 divided by the no of threads
I hit it right about 80 percent of time

I’m afraid that I need a specific example of the .75 idea. If I am cutting 8 TPI threads, .742 divided by 8 is .09275. Is .09275 the distance to go in? For a 1”-8, my major diameter was 1.000”. So I go in radially .09275” and arrive at .90725”. If so, does .90725 represent the value for the estimated pitch diameter?

 

[erikmannie]

So now I am cutting 1”-8 internal threads. I had to stop to look up the specs for a class B (or should I say Type B?) thread.

So far I have a .750” bore as seen below: