Prints failing - layer shifts to the side solved

[CB1 0]

Just got our Ultimaker 2+ Extended.  Less than a month old, made a handful of good parts.

But now, almost every time, it's shifting layers in the middle of a print.

What would cause this, and how can we fix it?

Any insights are appreciated

Thanks

Edited April 19, 2016 by Guest

[CB1 0]

Latest print shifted even sooner

So we tightened the 4 screws for each motor, based on reading other threads (thanks gr5). Tightened them down tight, bending the allen key on each one.

Are there other screws that need to be tightened?

Seems to be printing better so far, time will tell

[peggyb 169]

also tighten the grub screws on the pulleys, all 12

http://support.3dverkstan.se/article/23-a-visual-ultimaker-troubleshooting-guide#shifted

[CB1 0]

Well, tightening the outside screws and lubricating the rails didn't work.  The next print was worse than before.  Originally shifted in the x-direction, this one shifted in x and y directions.

Thanks Peggy, I've just tightened all those grub screws.

Also the rails were out of alignment.  So first I aligned them, using your link above.

Then I used a Bondhus brand hardened 2mm allen key (hex) to tighten down all 12 grub screws very tightly.  The weaker, cheaper allen keys (including the ones that came with the UM2E+) seem to just give way, stripping themselves or the grub screw.  

Thanks to gr5's suggestions here:

https://ultimaker.com/en/community/6768-how-to-tighten-x-y-axis-set-screws

[CB1 0]

Aligning the rails, and tightening all 12 grub screws worked.

Printing beautifully now