websterz,
My 8 X 20 Grizzly has a 16tpi. I wondered why I couldn't cut a good Imperial thread.
The lathe is going to go through a total rebuild. I've already started on the frame al Bogstandards fix of (i think it was ) Darren's lathe. Not going to put threading capabilities on it though. I have the Logan lathe for that.
I was also thinking of going for an ACME thread but maybe 1/2-20. Might even try to cut my own using the Logan.
Unfortunatly right now I'm to busy with "need to do stuff" that doesn't include playing in the shop.

Bernd