08-18-2016, 02:00 AM
On the lathe: rig a tool post mounted milling spindle holding an end mill. set gear train for your coarse thread and cut the thread. Probably best hand turning the main spindle rather than using power. A simple milling spindle belt driven from above was very common to see in home work shops before cheap import mills arrived on the scene.
Andrew Mawson, proud to be a member of MetalworkingFun Forum since Oct 2013.