- Joined
- Apr 8, 2013
- Messages
- 1,982
When I have to thread right up to a shoulder (if I can't use a relief groove) I shut off my spindle power with about 30 thou of feed left to go. At 70 rpm the spindle will coast for .020 (+/- depending on the pitch) and I use a chuck key to turn the chuck for the last .010 inch of thread to snuggle right up to the shoulder. The thread comes out better than what I could do even at 20 rpm. I have dial indicators on my long & cross feeds.Those of us who are older and get easily distracted need things slowed way down. I still remember my first few attempts at threading on a manual lathe, about the 4th or 5th pass it sounded like...GRRRRRRAAAAAHHHHHHH...spindle stall.