I'm having a problem with my RAMPS 1.3 electronics and the extruder motor. Whenever I tell it to move, it jitters one way for about half a second and then half a second later it begins to jitter the other way. I've tried plugging the Pololu board into another socket, and the behavior doesn't repeat even with the same board and motor. It occurs on either extruder socket (changed in firmware). I'm using Sprinter firmware with the pins configured based on the board schematic. Does anyone have any tips?
If you are using RepSnapper try reducing extruder speed in the control panel the default in RepSnapper is too high for the default e steps/mm in Sprinter.
I figured it out; I was using a stepper motor with a hugely different mix of voltage/current requirements. I'd recommend steering clear of using SparkFun stepper motors to drive your extruder =) Buying another, higher torque motor solved the problem for me.
