extruder stepper motor not moving correctly.

[rexrussell]

This is my first assembly of the rostockmax. im almost finished.
I have been having a terribly difficult time getting the motor that controls the filament feed to work properly. when i send the command to extrude it seems to just wiggle back and fourth. I have adjusted the wattage per the updated instructions without success. I have changed the motor and still having the same issue. Even when i plug a new motor directly in to the board I still get the same results. I believe that the problem lies between the firmware and software. Any help or Direction is greatly appreciated.

[Captain Starfish]

Does it look like it alternates one step forward, one step back? It's not channeling Paula Abdul, most likely just one pair of the stepper wires is the wrong way around. And I've seen them come from other supplies before with a fairly arbitrary mapping of wire colours. You never know: might be worth a try.

[Polygonhell]

If it's just wiggling back and forward either it's wired incorrectly, or you have a lose wire between it and the driver.
Check the wiring order on the connector, if it's correct you need to check all the wiring between the board and the stepper. Unfortunately it's quite possible to have wiring that shows continuity on a meter, but isn't good enough for the stepper to work.
I had a bad connector on the second extruder I added, and it took me several attempts to isolate exactly which piece of wiring was bad, in my case if I tried to move the stepper, so the motor was enabled, then wiggled the workaround the connector, I could see the stepper twitch, but there is no guarantee of that.

It's also possible that you have a bad driver on the RAMBO board, but I'd start by assuming that isn't the case.