Notifications
Clear all

Troubleshooting sudden print offset  

  RSS
rudye.m
(@rudye-m)
Active Member
Troubleshooting sudden print offset

Hi Everyone,

Any advice on how to troubleshoot and fix this issue? My printing seems to go fine, but every so often it develops an offset. The example here (top of the crown) is after printing trouble free for about 16 hours.

Incidentally, I had this same thing happen attempting to print the same model (scaled smaller), but it happened after only an hour or so while printing the bottom. Suddenly the print jumped position by probably 3-4 mm.

I appreciate any ideas about how to fix it.

Posted : 03/09/2018 8:25 pm
luca.w
(@luca-w)
Active Member
Re: Troubleshooting sudden print offset

Hey,

are there any crashes during the print? I would try to look at the gcode through a gcode analyser!

18 y.o. student in Germany who is interested in engineering...
Posted : 03/09/2018 8:28 pm
Peter L
(@peter-l)
Honorable Member
Re: Troubleshooting sudden print offset

Check that the X and Y axis pulleys are properly attached to the stepper motors. The lock screws should be as tight as possible and locked against the flat part of the motor shaft.

Loose pulleys are a common problem on newly built printers. If you don't get it tight enough to start, the screw can back out a little and allow the pulley to move around a bit on the shaft.

Posted : 03/09/2018 9:13 pm
rudye.m
(@rudye-m)
Active Member
Topic starter answered:
Re: Troubleshooting sudden print offset

Thanks for the suggestions!

I looked at the gcode file in an online analyzer. Its difficult to find anything specific, but I did notice that the area wear the problem started does seem to be one of the faster traveling parts.

My working theory right now is that the y-axis belt is too loose. Perhaps in this fast traveling part there was enough backlash in the belt that it overshot a tooth.

peter.l22 The motor pulleys seem to be tight. I've had this printer assembled since the beginning of the year, and this sudden offset issue has only happened recently.

Posted : 04/09/2018 1:58 pm
Share: