Spur gear source?

You know I can't remember over the last 50 or 60 years since I finished my apprenticeship of ever seeing a professional machinist use a thread dial :-)

This is not to say that no one ever used one, just that I never saw one used.

Greetings Gerry, The gear should ideally have helical teeth so that the threading dial will still be at 90 degrees to the leadscrew. But you may have a hard time finding one. However, the gear only has to transmit enough torque to spin the thread dial. You could get away with a disc with pins sticking out as your gear. The pins should be tapered to match the angle of the leadscrew, just so that there is line contact instead of just point contact. If a regular spur gear is used, one with straight teeth, only the corners of the leadscrew thread will make contact with the gear teeth unless the axis of the gear is tilted to the same angle as the helix on the leadscrew. Eric

You have to ask?

Reverse the lathe.

Aren't they cutting metric threads?

--jsw

I finished my apprenticeship in 1950.... I don't think that they had metric threads in those days :-)

Assuming a standard Acme thread on the leadscrew, go for a

You'll need to mount the gear at a sight angle to make the teeth parallel the thread faces.

If you had an index head -- or something which could work like one, you could set up the lathe to do milling well enough to do the job, and turn a cutter to make the cuts.

Sorry -- my newsreader does not do e-mail forwarding as set up. I hope that you find this here.

You need to get a newsreader with a good killfile, and use that to get rid of most of the junk -- by name of poster, and by words in the "Subject: " header

Good luck, DoN.

Are you really that silly or are out making an effort? You don't cut threads when you reverse the lathe. Well, most people don't anyway, of course if they do they have very poor results.

Geeze, 60 years old and hasn't learned a thing.

Goodness, and you have a reading disability, or is it "aphasia" which is frequently a result of stroke?

In the future I will try using words of fewer syllables as I understand that those suffering from the disability have fewer problems comprehending simple words.