Every so many layers the print shifts to the right

[jclemens]

I have a Solldoodle 2 with head bed . It has worked well for the past 1.5 years. suddenly now whenever I print something every so many layers the print shifts considerably to the right.IMG_5092.jpgIMG_7570.jpg

[Mjolinor]

You probably have a tight spot on the X axis shafts. Try it with power removed, moving it by hand, maybe you can feel it. If not then try slowing things down, print and non-print moves.

[Davo]

You probably have a tight spot on the X axis shafts. Try it with power removed, moving it by hand, maybe you can feel it. If not then try slowing things down, print and non-print moves.

If nothing there, slow down your fastest moves by 10% and see if that helps.

[LambdaFF]

All of the above + belt tightness ?
If not, start checking your motors (for instance, swap X and Y axis to see if it happens again on that axis)