I have a Cummins 7x12 minilathe and a nicely hand-ground Acme profile tool
I made. Right, so I have to cut a worm at 6.4 tpi. the change gears
with my 16 tpi leadscrew will be:

(30/50) x (40/60)

Can SKS tell me how to set this up so the gears actually mesh? Do I have
to somehow interpose an idler in there somewhere?

Help!
Mike in BC