Cutting threads by hand

[Martin Pansch]

I have done a few projects now where part of it included cutting male threads in a forged piece of mild steel. I am cutting the threads by hand with a die and t-handle. I have been able to get ok threads cut, they work but aren't pretty. My biggest issue with them is that when examined closely the threads have little tears in the metal. If I were home I would post a photo but alas the Army still has me.

As I mentioned these are parts that are forged round. They are then descaled filed clean. I use relatively new dies (bought new, only used a few time), though of box store brand. I use a store bought thread cutting oil and back the die off every half turn or so.

Are there any tricks anyone has to cut smoother threads?

Thanks.

Martin

[Jim Moenck]

I have always had the same problem. I did some quick research on the net to try to find some info. I had heard of thread forming being better than cutting dies, but from what I see they are only available for tapping holes and not for threading round rod. MSC has their hex dies which most of us probably have. They state that these are for dressing and cleaning up round rod that is already threaded, not for cutting new threads.

They have a split die thread that is adjustable, made for cutting new threads. They are adjusted by/with a set screw. You cut new threads a little at a time, checking for fit after each time, until you get the right size. I need to check into these a bit more.

[Aarono]

I did a bit of manual(by hand) thread making(with a die) while in school and it was never very pretty. Using a lathe with a cresting insert made for threading is really the best way to get a nice looking thread. If you knew someone with a manual(non-CNC) lathe that would work, I'm sure. Or a CNC lathe :)