PM1127 motor seizes up when parting

Not sure if it's the overload. The motor is still humming like it wants to spin, but the steel is preventing it.
 
What RPM are you parting at? (Prior to seizing, of course.) ;)

Tom
 
I've only seen that on mine when feeding way too fast or the tool catches on the metal and binds rather than cutting. Can you show us a pic of the setup? I've almost totally eliminated parting problems by using a rear mounted solid block to hold the parting tool. I know you said you sharpened it, but running too fast could dull it. It doesn't sound like that should be the case with 1" 1045 though. Could it have work hardened?

Note that you get lower torque from the motor with the dial turned down really low. I find for 1" that 200ish works well. I don't have any 1045, but I've done 304 stainless without much hassle.
 
Yea it catches on the metal and stops. The thing is, I didn't have this issue before. If I do autofeed on the slowest feed rate, it still does it.
 
I emailed Precision Matthews a few days ago, still waiting on a response
 
I guess if there is a problem with the motor or VFD it could be something they would be able to help with. I honestly think that you're getting a little movement somewhere that's binding the tool. If you are using the normal setup with the QCTP on the compound, then there is slight movement you can't get rid of. The parting blade holder it comes with holds it at an angle, I think that contributes to the problem by increasing the possibility of binding when things move. I got less chatter and binding when I used a setup with the blade held flat.
 
Check your tool height. If the tool is above center, when the tool grabs, it drives it deeper into the work guaranteeing a stall. Tool holder geometry is complex because there are a number of places where flex can occur. The tool can flex from play in the carriage, the compound, the tool holder and the tool itself. It varies from lathe to lathe.
 
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