Printer is offsetting layers and scrunching Y axis movement

I stopped the print before it would have got to this state, Ill take photos of it on Monday to provide a more concrete explanation  of what is going on. I don't know if the offset it consistent or random yet, I suspect it has some pattern. It's not a brand new machine, but before last week it was working fine.

I'll get some pictures.

Thanks lawsy! I'll try those things you suggested!

So I jinxed myself and had a layer shift just after posting.

Next step was to adjust the stepper motor driver trimpots. Each was about 0.02V out.

I also turned my non extrusion travel speed down to 130 from 150.

The soliwiki link posted by op7ical is essential for all us newbies. I would also suggest making shifting x/y axis problems a sticky. It really can be a multi pronged problem.

For me the cure was lube, belt tension, more accurate and rigid y axis idler blocks, 40mm fan for  x stepper,  40mm fan for electronics, and finally, adjustment of trimpot voltage.

Is it possible that the Y motor is giving up?

It sounds mechanical Lawsy. My carriage is dialed in really good now and it moves effortlessly, even if you push from just one side. I found that when replacing my cracked idler bracket that my idler pulleys had almost no grease on them. Without grease here I would imagine the aluminum galling fairly quickly on the steel shaft (cap screw).  I use a Teflon oil for the bushings on the jack shaft to make sure the lube gets way in there (will upgrade to y axis bearings one of these days). I use ultra lube white lithium for shafts, lead screw, and front idler pulleys. And, the belt from my stepper to the jackshaft is really tight (if not i would get a lot of backlash here on my particular printer). So, even with tight belts it moves easy.

Mithrandir, looks to me like there are all sorts of issues. Be sure to level bed, set z-tab to squish first layer, calibrate extruder flow, put a fan on the controller board to keep it cool, grease all rods and pulley shafts, adjust belt tension, ensure no binding of filament, etc. Have you been to soliwiki and gone through all the calibration steps, as well as the other things just mentioned? I did all this and my printer works great. Solidoodle has a couple videos that are good too, and also the instructions for adjusting your trimpot voltages.

I would go through all the calibrations again. Even the trimpot voltage. It's important, IMO, not to miss any of the steps. All are really important.

As for bent jack shaft, this is caused from having the stepper to jackshaft belt too tight, which, you sort of need to have tight, otherwise you can get a bit of elongation in your printed holes. Smitty50500 had a recent post, which I can't seem to find at the moment, where he took my reworked front idler brackets and added bearings, as well as a pillowblock bearing to the jackshaft. It's really good stuff, so search it out. When I upgrade my bushings to bearings, I will use Smitty's pillowblock and reworked idler brackets. Again, just search it out on this forum. As for the pillowblock, it will allow you to keep your primary y axis drive belt tight, without deflecting (bending) the shaft. Keep in mind, you can make the belt so tight you can't even move the y-axis. Good luck!

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