Motor control

Hi guys.

Hopefully you will be able to help me with a little problem Ive run into. Im in the process of building a RepRap Prusa Mendel iteration 3. The electronics is a RAMPS 1.4 Shield on an Arduino board. I was testing my electronics today and it seems my Y-axis does not function properly, so Ive been troubleshooting.

When Y-axis motor is connected to Y-axis stepper controller, it functions sporadically. The motor vibrates and wants to move, but doesnt or only moves in jolts/jitters. When Y-axis motor is connected to X-axis stepper controller, it functions perfectly moving smoothly.

So it seems the problem is with the Y-axis stepper controller. However, the fact that the motor does vibrate and moves in jolts tells me that the controller is not burnt. Do you have any suggestions before i tear apart my electronics to do a resoldering of the Y-axis controller? I have checked the current already to the stepper controller and that does not seem to be an issue.

i would plug the x axis driver into the y axis slot and see if that works. if it does work, the drive is faulty, if it doesnt, either the ramps, arduino or firmware are at fault.

edit. have you checked the current the driver is set to? to high, or too low can cause similar issues that you are experiencing

Edited 1 time(s). Last edit at 04/30/2013 05:33PM by lazzymonk.

Good suggestion, I'll try swapping drivers tonight. I checked the voltage, it was initial the same across all drivers and Ive since turned that particular board up a bit in an effort to solve the problem, didn't work tho.

much better idea is to check if the stepper motor will work on the second extruder driver and if it works try swapping the stepper and y axis frivers.

I tested the second extruder driver and that works, fine. The motors also run a lot more smoothly when operated at 1/16 of the steps/mm, which suggests that it is the microstepping which is not working correctly. This would cause the motor to require less power and therefore be overpowered at 0.4V. The bad thing about faulty microstepping is that only cause I can really think over right now is that soldering of the jumper pins for microstepping is not working - which means that I have to disassemble the RAMPS Shield and the Arduino. Desoldering is not really my thing.