10-22-2013, 03:43 PM
Ed, looks to me (a real novice) that there is some backlash or slop somewhere in the gear train driving your leadscrew. Possibly a sheared key? I too, would advise leaving the half nuts engaged and reverse the lathe. I do it for all threading, metric or imperial, and my lathe has a 16 tpi imperial lead screw. Just try it and see if you're results improve.
Chuck
Chuck
Micromark 7x14 Lathe, X2 Mill , old Green 4x6 bandsaw
The difficult takes me a while, the impossible takes a little longer.
The difficult takes me a while, the impossible takes a little longer.