Y-Axis shifting on AO-100

Hello folks, my machine has been producing some very nice quality prints as far as consistency and uniformity. However, this print http://imgur.com/a/5D6xa had some Y-axis shift in about layer 65/113. The driver was not hot, the only one hot to the touch was the X-axis driver. I’ve since added heatsinks and will report back.

If anyone sees something obviously wrong, please let me know. Thanks in advance.

0.5mm dia nozzle
3mm ABS filament
gcode attached:
jonaskuehling_gregs-wade-v3_idler-only.gcode (1.06 MB)

I had a big reply typed out for this, but the forum just ate it. Basically you are getting Z banding and Y axis belt tension issues. To fix it you need to upgrade several parts. The equired upgrade parts are the 16 tooth motor pulleys installed via a firmware update as outlined here: http://www.lulzbot.com/?q=blog/upgrade-your-ao-100 (you will need two http://www.lulzbot.com/?q=products/gt2-16-teeth-timing-pulley ), the Lower X end clamps (included in this set or print from the AO-101 files (http://www.lulzbot.com/?q=ACME-Pillow-Block-X-End-Set-2.0), A Y axis tensioner (http://www.thingiverse.com/thing:219227 or the one from the AO-101 download part files) and the Z endstop that fits the lower X clamps. (it’s in here http://download.lulzbot.com/AO-101/parts/)

Optionally you also want a X axis tensioner (http://www.thingiverse.com/thing:28138/#files ) and eventually the AO-101 beefier couplers. The lower motor mount for the Z motors is optional and not required, but it does give you more clearance.

After you upgrade at least the minimum parts your print quality should improve dramatically. At that point you have some options for further upgrade if you want, such as the AO-TAZ project TAZ style X ends or even further than that.

The printer really isn’t usable without the minimum upgrades in my oppinion.

Been reading and it seems that’s the right direction i should be heading in. Didn’t know about the tensioners though. Thank you for your input and thanks for typing out your response again! Much obliged!

Well now that i think of it, define usable. Can i print those parts to make it usable or will i have to get them printed off a machine that is defined as usable?

You can print them, they may not look pretty, but they should be close enough to sound. I ended up purchasing the lower clamp pieces from lulzbot because the ones on my used A0-100 were damaged on one side when I got it anyways and it wasn’t printing correctly. I could have probably made something work, but I was getting even worse prints than the one you had pictured before that point. the clamps and the 16 tooth gears are the critical upgrades, everything else helps dramatically. the Y tensioner I’d oribably also call critical, but it is theoretically possible to tension the belts without it. THe Z endstop is kind of critical to work wiht the lowered X end clamps, but you can modify the existing one to work if you forget to print it the first time like I did.