Reverse Extrusion/Retraction on Ultimaker Original Motor

[stratman-rik 0]

Hello

My name is Rik, I am the Design Technology technician at Wimbledon College, London. We have recently purchased two Ultimaker Original 3D printers as self build kits.

The first one to be assembled is functioning very well with no problems, the second kit however has a problem with the extruder motor running in reverse.

This fault was reported to Ultimaker who have since kindly sent a replacement motor but unfortunately even this new motor also runs backwards which must mean the fault lies elsewhere.

I can assure you that the greatest care has been taken assembling both of the printers and as the first printer functions well I've taken the time to compare both units to check for any assembly errors. I've also swapped over the motors between the two printers to confirm that the problem is definitely not the motors, as they all work on the first printer.

It was suggested that swapping over two of the wires in order to reverse the motors polarity might be a solution which did indeed work in getting the extrusion working but there is still a problem with retraction squirting out plastic. I've also tried additionally swapping over the remaining two wires but this only resulted in the motor juddering.

I would be very grateful for any guidance in how to proceed with this matter.

Kind Regards

Richard Martin

 

[twistx 0]

Hi Rik, did you upgrade Marlin when prompted by Cura on both machines?

If not, try that first. Maybe the machine that has the issue was reversed in software for some reason.

If you did do that, but the extruder motor was running in reverse for both extruding and retracting directions, I would download Marlin and set the reverse option for that motor to true in the configuration file. Compile and upload the sketch. Be sure to restore the stepper leads to their original positions if you do that though.

This should be the line to edit:

https://github.com/daid/Marlin/blob/Marlin_v1/Marlin/Configuration.h#L296