-
Welcome back Guest! Did you know you can mentor other members here at H-M? If not, please check out our Relaunch of Hobby Machinist Mentoring Program!
How to make a Thread dial Gear
- Thread starter mac1911
- Start date
- Joined
- Feb 1, 2015
- Messages
- 10,080
My Grizzly 602 has a 12 tpi lead screw pitch and 12 marks on the half nut dial. The gear has 36 teeth so it rotates one complete revolution in 3". My Atlas/Craftsman has a lead screw pitch of 16 tpi and 4 marks on the dial. The gear has 32 teeth so the dial rotates one complete revolution in 2".
For a 10 tpi lead screw, you would want some multiple of 10 teeth so a complete revolution of the dial occurs with a whole multiple of 1". How many teeth the gear has will also depend upon physical clearance as the gear has to engage the lead screw and does so by rotation of the thread dial shaft axis.
If you had 20 teeth on the gear and had 2 marks on the thread dial, each mark would correspond to a change of the position of the carriage of one full inch. Since inch threads repeat every full inch, engaging the half nuts on either a full revolution or a half revolution will result in maintaining the synchronization between the carriage and the spindle. For half integral threads like 11.5 tpi, engaging at the same mark will ensure correct synchronization as the threads repeat every two inches. Past that, I'm not sure.
For a 10 tpi lead screw, you would want some multiple of 10 teeth so a complete revolution of the dial occurs with a whole multiple of 1". How many teeth the gear has will also depend upon physical clearance as the gear has to engage the lead screw and does so by rotation of the thread dial shaft axis.
If you had 20 teeth on the gear and had 2 marks on the thread dial, each mark would correspond to a change of the position of the carriage of one full inch. Since inch threads repeat every full inch, engaging the half nuts on either a full revolution or a half revolution will result in maintaining the synchronization between the carriage and the spindle. For half integral threads like 11.5 tpi, engaging at the same mark will ensure correct synchronization as the threads repeat every two inches. Past that, I'm not sure.
- Joined
- Apr 30, 2015
- Messages
- 12,418
20 teeth sounds good to me
Similar threads
