Threading on a PM1127 lathe - turning instead of threading

I'm trying to figure out why the top gear wobbles. If I tighten the nut to keep it straight, it seizes the gear because it's being sandwiched between the spacer and the washer on the other side.
 
The nut should tighten up against a shoulder on the shaft before the gear is pinched. You may need to remove a washer.
 
Adjust the "odd nuts" to allow movement without getting too loose. Make sure the washers are on the right sides as well.
 
My threads aren't going on the same place. The manual says if you're doing metric, to not use the threading dial. I have it set at 1.25 pitch

I take off .002 at a time. I thread from right to left, I turn off the emergency stop, I back out the cutter, then turn on the machine, then turn the directional from left to right. Then I hit the emergency stop, then turn on the machine, move the directional back to right to left, then it cuts on a different area.

Not sure what I'm doing wrong. It says to keep the half nut engaged at all times when you're doing metric threads and I've done just that. It keeps cutting on a different area when I come back for the second cut, which is also at .002 depth of cut.

*edit*

Redid the gears to where I'm cutting 24 TPI. I'm still trying to figure out how to use the threading dial. Not sure how it works.
 
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You're reversing the motor electrically to back up to the start of the thread, right? Don't shift any gears or you'll lose the indexing between the spindle and the lead screw.
 
Yeah, don't use the direction shifter. Use the motor reverse switch.

For the TPI thread, even pitch threads can use any number on the thread dial.

Set position and cut depth with the machine running.

Wait for the thread dial to come to the right number, engage the half nuts.

Disengage when you are ready, move the carriage to the start and do it again till you get to the right depth.

There are tons of YouTube videos that demonstrate the process and it's basically the same on every lathe. Consider Joe Pieczynski's away from the chuck video as well.
 
I never tried with Forward/Reverse motor switch. I was using the leadscrew directional lever.
 
That won’t work. You have to use the motor direction. Do not take it out of gear, or change gears, until the thread is finished.
 
On my mini I lock the half nut and cut the thread. I stop the motor at the end of the thread. Next I put the forward/reverse switch into reverse then back out the cross slide. Then start the motor and let it reverse until I get past the thread start by a quarter inch or so. Stop the motor, put the forward/reverse switch into forward position then adjust the crosslide back to its zero position and set the depth of cut then start cutting the thread again. Repeat the procedure until the thread cut to depth.

Roy
 
Ok, that worked! Now I just gotta figure out how to make the gears less noisy.

The threads came out at an angle, though. I need to turn the QCTP a bit more.
 
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