Lead Screw & Split-Nut Assemblies
Entire lead screw.
Split-nut engaged.
To not cross threads I move the lead screw handle back & forth while
engaging the split-nut.
An Acme square-shaped thread might have helped this potential problem.
Detail of split-nut, engaged. The spilt-nut
assembly is low enough so as to not interfere with
the carriage stop bar function & also clear the spindle housing allowing full carriage
travel.
If I had it to do over, I would have investigated using a
left-hand Acme (square-shaped) thread.
Full-sized lathes use such a lead screw. Finding the proper left-hand tap &
threaded rod might be difficult.
A removable cover of some sort might be nice to keep the chips out since you
have to be able to clean the split-nut area.
Detail of split-nut, disengaged.
Split-nut under spindle housing. A
variable-speed motor with clutch has
been added.
Reamed ¼" ID bronze bushing to eliminate
lead-screw flexing.