MakerGear Forum

Is this the sign of a bad stepper motor? Link to Youtube Video

My printer has done this in the past once or twice but after restarting a print it always seemed to work fine again. It hasn't done it in months but today I had to stop the print after the first few layers because it sounded like the nozzle was dragging but now (above video) is what I get when trying to jog the printer. I have a wonky liner rail and while it seems like it moves fine still I thought that might be the problem so I pulled the belt off the motor but the motor still does that shaky grinding thing without turning much. I tried swapping the x and y connection on the board to see if that helped but still no go.

Any thoughts? or should I just order a new stepper?

-Steve

sthone wrote:Is this the sign of a bad stepper motor?

Steppers have basically one moving part (the rotor) and no internal connections, so they're generally the last thing to fail.

I'd expect a broken / intermittent wire in the cable from the RAMBo to the motor, probably at the point where it attaches to the Y axis stage out there in the back. You'll probably have to disassemble the loom and extract the wires before you find the problem, though...

Thanks ED, I think you were right.

I cut the zip tie and took the motor off and plugged it into my other printer and it spun fine. Of course when I put it back on the original printer and now wiggling the wire everywhere I can't replicate the problem. But it's working at the moment so that's good. The portion of the heat shrink tubing around the wires where it was zip tied to the motor looks pretty kinked/worn so I''m guess that's where the problem might be. I think what I'm going to do is design a bracket that clamps to the motor and holds the wires a little more secure than the zip tie does.

Thanks again for the quick help,

-Steve

Tim made one: http://www.thingiverse.com/thing:276095

That's for the HBP, (I run a Bridge for that) I need one for the stepper motor wires.

-Steve

Came up with this quick bracket, I'll have to see if it helps at all.

-Steve

Nice. What are those threaded inserts that go in the inside on the left?

Those are Brass Heat Set Insert for Plastics from McMaster-Carr they are pretty cool I use them on a lot of my projects.

-Steve