Layer shifting every print

[macua85 52]

Ok, give me some ideas guys. I keep getting failed prints on my ultimaker (my genuine one) at the moment. It's ironic my one made with cheap chinese parts is more reliable. Backgrounds info: it's direct drive with gt2.

It just failed a 14h print during the last hour. I keep getting layer shifting, usually in the Y direction but sometimes both. Sometimes only a few mm, but enough to ruin print, sometimes a seismic shift. The axis are silky smooth with no catching or tightness anywhere. Pulleys are all super tight as are the couplings from motor to shafts. I'm stumped. No idea what's causing it. Happened on the last 5 prints I've attempted, same model file (which is sound, no issue with that). So much wasted filament! Could this be a stepper or stepper driver issue?

Any help much appreciated, I can't keep wasting xt at the rate I am!

Thanks

[macua85 52]

Come to think of It, there was a preceding event before this problem. I left it on a print overnight, and woke up to the printer jammed and plastic pubes all over the place. The y rod had some sticky shite on it which caught he bearing a seized it all up solid. The x coupling was also rubbing against the plastic mount too. Think that could damage the stepper drivers or motors?

[tommyph1208 55]

Seems to me the only place left is the drivers... Try swapping them around xy for ez, see if your problem moves

[macua85 52]

I have a few spares, I'll try putting those in. Maybe the heat sinks have detached. Will

Check that too. Am I right in assuming prolonged skipping would be more likely to damage the driver rather than the motor?

[tommyph1208 55]

I have a few spares, I'll try putting those in. Maybe the heat sinks have detached. Will

Check that too. Am I right in assuming prolonged skipping would be more likely to damage the driver rather than the motor?

 

I think that is a safe assumption yes... I think you have to treat your motors very bad for them to get damaged.

If you find that you have to replace stepper drivers I can strongly recommend the SilentStepSticks from Watterot

[macua85 52]

Any changes to make firmware wise for those?

[tommyph1208 55]

Any changes to make firmware wise for those?

 

Yes a bit... They interpret the step signals reverse of the original drivers... so you have to either reverse the motor cables or invert all axis in firmware.

They also don't support 1/8th microstepping, so you have to switch a jumper on the board for the z aksis and double the steps in firmware... But that is it.

If you come to it, read through the relevant posts on the forum:

https://ultimaker.com/en/community/view/10332-new-part-day-silent-stepper-motors?page=1

and

https://ultimaker.com/en/community/view/11571-step-by-step-installation-of-silentstepstick-drivers-on-umo

Be sure to read through it all since, even though it is actually extremely simple to install and use them... It took people (incl. myself) a bit of trial and error to figure out the most simple aproach...

reading it all, provides a good overview of what exactly the differences are, and WILL land you on the right track in terms of installing and using them in the simplest (and best) way possible...

[SandervG 1,518]

Maybe they just overheat, you could elevate one side of the Ultimaker so you have a better airflow at your electronics. Is the fan still working? If it is only working a little bit that may not be sufficient.

I think you mentioned it, but the pulleys which are easily overlooked are the ones directly on the motors.

Good luck!

[macua85 52]

Hey guys,

So i've glued (witt arctic thermal glue) larger heat sinks onto the umo steppers and replaced the Y stepper with a spare I had. Also cut some slots at the end of the stepper channel in the fan cover so the hot air can vent out properly. Hopefully all this will make the difference!

Thanks for the input, will update if its not sorted.

Edited September 1, 2015 by Guest