Quote Originally Posted by John S View Post
You will never cut an accurate thread for a leadscrew with a die be it imperial or metric.
Quite correct. You'd be better off just bodging something with a bit of threaded rod!

Irving;
I've just been looking at Tony's lathe site: If the lathe has any historical value I suggest you do not cut the nut as I suggested, it would devalue the lathe considerable.

I'd offer to make you a LH square threaded nut (sounds like a challenge :)) , but my Hardinge will not cut 8 tpi (a major PIA).

I think the best thing to do would be to replace the whole handle, screw and nut. Perhaps using the TR10x2 trapezoid with a metric dial, although I agree with John, adapting a part from another lathe could save a lot of work.