Layer Shift

have had issue after issue but one that seems to never go away is this layer shift I get on longish prints. It is only the y-axis that it occurs on and often will happen 2 or 3 times separated by 10 or less layers then it will finish the print normally. I am running two acrylic sheets, heat bed and 200x200mm glass on the y axis with linear bearings so I don't see how this should be a problem. I have thoroughly lubed the linear bearings ad inspected them, they make a little more noise than I would like but move freely and smoothly, is there a special lube I should be using? The y motor certainly isn't working as hard as the E motor.

The only thing I can think of (even though it doesnt fit symptoms in my opinion) is to adjust the "pot" on my y stepper driver (Printrboard) which I have no idea how to do. Any ideas?



Edited 1 time(s). Last edit at 07/29/2012 11:34AM by RegionX.

I saw this for the first time today on my Prusa. I went from printing the calibration tower (shown in pic) to the hollow box (bridging test) and all of a sudden without any configuration changes at all the Y axis started to shift after every layer (a very consistent shift it seems).

The only thing I did between those two prints is change out the filament from white to orange.

I had this happen to be in the beginning, it was the exact same problem as your orange parts show. I fixed it by adding a 120mm 12v fan blowing down onto my electronics board, because I presumed it was caused by the X axis motor skipping steps because of overheating. I no longer have this problem, but my prints are pretty noisy because of that fan. You might also want to try turning down the pot on the driver, as it may be giving too much current which in turn causes escessive heating.

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Charles S.
Software Engineer
Prusa Mendel I2, RAMPS 1.4, Marlin 1.0 R2, Pronterface, Slic3r