extruder motor not turning

My extruder motor doens't turn. It just sits there and clicks, but doesn't not turn the gear. I checked with the power off the and motor turn fine. I turned the trim pot down and no clicking, then turned it back up but it just clicks. Any ideas what is wrong?

People may need more than this.

What electronics?

How are you sending instructions?

How are you testing the extruder?

What are you using to generate gcode or not there yet?

Have you tried the motor on a working extruder controller?

NEVER DISCONNECT STEPPER MOTORS WHILE THE POWER IS ON or you will blow your circuit board...

1. Make sure all four (4) wires from the motor to the driver are in good shape. To do this, unplug from the driver board, and turn the motor by hand. It should be smooth, but slightly steppy. Now short A+/A-, and turn again. It shuld be very steppy, even a bit hard to turn. Repeat for B+/B-, with same expected results. Now short all four together. It should be very NOT steppy, smooth, with considerable resistance. If any of these behaviors is different, check the wires and connectors for continuity.

2. If the motor vibrates, but dows not turn, and you are confident that you have set the current to a good level (motor is warm, not hot), then chances are you have a blown (partially) driver.

3. The motor should be able to turn smoothly under powered control without missing steps, even when you are holding the gear with some force. If it does not then driver is blown. I can speak to this fact, because I've had this problem myself.

In case anyone is intereased, I have run my POLOLU drivers without heat sinks, with no problems, but I added some in just in case. My motors are just barely warm to the touch, sho that should give some idea how far down the current is set. This can vary from motor to motor, and unfortunately, I do not have any specs on the motors I have.

It's also easy to send pulses too fast. In that case the motor will just hum without moving. Try really slow movement too.

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I'm building it with Baling Wire

I assume that you got the axis motors working already, but I do feel the need to ask if you're certain that you've got the motor wiring right. When I connected the motor wires wrong, the motor would just sit there and vibrate but not move anywhere.

Another test is to see if you can operate that same motor driven from one of the axis controllers. That will make sure the motor is fine.