Missing steps - Shifting layers

[holoped 0]

Hi,

I'm having problems printing large items. Smaller things work well,

but when items are big I get huge shifting mid-print (up to 2cm shift on some occasions). Some times several shifts happen during one print, with just a few layers in between shifts.

I have no idea where this is coming from. The belts are nice and tight.

Any ideas how to find the source of this problem ?

 

[owen 19]

It maybe a loose pulley. Check all your grub screws are tight.

 

[aaron 2]

This is probably not the solution but brushless motors tend to lose their power when they get hot enough. Are your motors staying cool enough?

 

[Nicolinux 288]

Another thing to check are loud grinding noises when the x/y or z axis move. If that's the case, check if you can move all axis (with the UltiController or with another tool).

 

[SandervG 1,521]

If it only and always happens with larger prints, i would also look into overheating of the motor or stepper driver.

Do you have all the heatsinks on them, and how about the fanduct on your electronics?

 

[gr5 2,224]

Original poster fixed the problem by oiling rods apparently (he cross posted in google groups).