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Slower speed selection

newbee21

Plastic
Joined
Feb 29, 2016
Hello to anyone whom can help with a question of how to slow a metal lathe down from its slowest registered speed of 105 to 50 or even to 70. I am trying to learn how to do threading at lower speed than my lathes slowest speed. please understand that i am just learning at my spare time. So i have no previous experience at this option or if there are options.
Thanks in advance to anyone.
 
Often one can go on the inter net and find a lathe manual.
A belt machine the bigger pulley turning a smaller pulley.
Some times a pull pin is pulled...and a gear you swing in.
often you may need to hand turn the chuck to makes gears fall into place and to know nothing is locked up from a wrong gear selection..some machines you can break a gear if the machine is gear locked.

some times you can go on youtube and see someone using the same lathe.
 
Thread in reverse, you won't have to slow down. Turn the tool upside down, reverse the thread screw, and stat from the chuck side threading towards the tailstock.
 
thread relief can only be 1/4" between ACME type and the next different type of thread and again to the next different thread all between centers. thank you for the suggestion though. Just trying to slow down speed of machine.
 
QT: [to do threading at lower speed than my lathes slowest speed.] The lathe can only go so slow with the motor going at a certain speed and the gears and/or belts transferring that to the spindle.

Reducing the motor actual speed or with a smaller motor pulley would reduce the spindle speed but continue to produce the chosen thread.

Perhaps you have a 3600, 1750 or 1160 rpm motor. you can see by percentage how much slower the lathe might turn with a slower motor.

With a variable speed motor the thread would be still correct, but the lathe would go as slow as you select.

*But 50 /70/100 RPM should be fine with a little practice/skill. Or as some have suggested you can travel away from the headstock with an upside down bit, going reverse..

Your compound at 30 (29 1/2) allows the pull out to pull away from the chuck..going forward.

I put a piece of tape on my chuck OD to see that tape come to 12:00 - 11:00 - 10:00 - 9:00 and pull right on the exact spot every pull.

Good to put a cut off broom stick in a lathe and practice thread cutting. Mark a line on that and thread right up to the line.
 
Not to be picking on you Newbee21 but your thread title could have been "How to make a lathe go slower?"

That way people with having the same problem could search a subject and find this conversation.

What have you concluded so far? Have you tried the 50-70-100 rpm that you mention and had problems?

Is the problem running a thread to a shoulder, or to the needed thread length with making a nice ending.
 
I wouldn't recommend you start learning to thread by turning the tool up-side down and running the late in reverse! First; you can't do it if you have a threaded spindle!Second; you can't see the cut! Third; you have to set the compound the opposite way! So you don't crash at the end of the thread undercut the Diameter of the material to be threaded to below the thread depth on the chuck side. If your using a center you can undercut that side too. Start with finer thread pitch, finer it is the slower the carriage will travel. And get a good book on threading, I have seen some really bad YouTube videos on threading and Don't us a carriage stop! Using it is a good way to wreck your machine!
 








 
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