UM2+ skipping steps

[njic 2]

Hi everyone.

2 weeks ago I bought UM2+ and love it. All prints came out perfectly with no issues untill last night. I was trying to print 8 h long run and layers were shifted after 1/2 print time. After reading this forum I found that someone was asking is motor belt rubbing on endstop cables. I think I have this is a problem on my machine. I can see that one of the small belts is rubbing on endstop. Not sure this coused skipping steps, but it doesn't look healthy. 

After 1/2 of print time the skipps started to happen and it continue almost untill the end of the print. The skips are all in the same direction.

 

What should I do?

 

I also attached the picture of last print which came outh perfectly. This one is made with almost the same cura settings.

[stu_le_brew 42]

If the belt is rubbing on the wires then they need to be pushed back out of the way, but the rubbing would surely effect all of the print. Its very simple to remove the limit switch (just two screws on the side) and push the wires back

 

looking at the print it would seem to me to be a problem that starts at a height as the first third of the big print looks OK

 

my first thought to solve the print problem would be to check all of the rods are correctly lubricated, then check none of the rods are loose and can move side to side or back to front

 

good luck

[njic 2]

Thank you for answer.

 

I think that Y endstop wires are in right place. As you can see on image from the first post;

 

 

lower wire heat shrink was rubbing against left panel. I guess that there should be more space between left panel and belt.

I know how to remove endstop and probably I could make more space by untwisting the wires. The machine was running for 34 h only and I wanted to check here before I touch anything.

I don't understand why would this rubbing cause triggering, but this topic got me thinking:

 

On 7/21/2016 at 12:02 PM, SandervG said:

Hi @Pieter90, welcome to the forums! I don't think this has anything to do with the filament. Since the shift is so erratic instead of just being skewed I don't think it is an pulley or belt that is causing it, but rather an end stop.

Could you check if they all still work properly?

Maybe the Y end stop (front) is rubbing against the pulley and that caused some errors during your print? (making it think it is being triggered?)

I think the rods are clean and well lubricated. I can see some oil on hot end bearing seals. There is almost same resistance when moving hot end in X or Y direction by hand.

 

BUT all rods can move left to right / back to front (axial direction only)!  All of them can move around 1 mm, but this one (Back X linear shaft, the one with Y motor attached on it) can move more than 2 mm

 

 

 

 Is this normal? Do I need longer spacers behind pulleys? Moving pulleys towards side panels doesn't feel right. If i move this shaft to the far right the belt is not touching wires anymore, but there is only 1-2 mm clearance.

 

I took closer look on failed print, and I can see that issues started to happen before layer shifting.

 

 

I guess it's more likely that warping happened and nozzle hit the part and printer skipped steps every few layers. Not sure about this, but I don't like idea of starting machine right now to do more testing.

 

What to do now? Should I investigate by myself or take machine to seller? I was hoping someone from Ultimaker team will suggest me 😄

[njic 2]

There is g-code in attachment if someone need. Sorry for long post

UM2_Luca_postolje.gcode

[stu_le_brew 42]

The movement shown in your second video is absolutely NOT correct there should be no movement at all you need to loosen the pulley an move outwards to prevent this movement

 

[njic 2]

I found Ultimaker tutorial for that. I'm curious how did I get perfect prints in first 30 h of printing...

Conclusion:

1. cable was out of it's place (there is slot in side panel behind cable)

2. Pulleys were not tightened in right place (almost all of them)

3. G code was bad

 

I solved everything and I'm happy to continue printing 😄

 

stu_le_brew thx for everything.

good luck

[stu_le_brew 42]

my pleasure

 

good printing

S