Missing steps/shifted layers on Y axis - have tried everything

@daufhammer

I had a similar problem also with my Y axis and in the end I realized that the default acceleration setting in the firmware was way up at maximum 9000mm/s^2. As soon as I set that to a normal (1000- ) 2000mm/s^2 and a normal feed rate everything works perfectly now.

Have you had a look at the acceleration and speed settings for the Y axis? From pronterface you can issue an M201 X1000 Y1000 and M202 X1000 Y1000 command to set the acceleration after the print has started and see if you still get missing steps. If not then check / correct the default acceleration setting in the firmware accordingly.

Edited 3 time(s). Last edit at 06/20/2012 05:24PM by dzach.

So i feel really bad because i started this thread a long time ago and thought i posted that i solved the problem, but must have totally forgotten to post what the problem was.... Hopefully it has helped people see the many different causes of missed steps and how to fix them...

My problem ended up not being missed steps at all, and was indeed mechanical like we all thought since i had checked and confirmed every potential electrical and firmware problem. The problem was that after attaching my hot end to my X-carriage (nice and tight), it must have softened the plastic a bit after heating up so it was able to wobble back and forth along the Y-axis.... this combined with a less than ideal system for holding my spool of filament caused the hot end/nozzle to move around enough that my layers didn't line up in the Y direction.

To solve the problem, i first just re-tightened the bolts holding my hot end to my X-carriage, but eventually printed a new X-carriage and made sure to put a fan blowing across the top of the hot end/bottom of the x-carriage to make sure that the plastic (PLA) didn't soften anymore.

So i guess this is one other area for people to check who are having what looks like missed steps in the Y-direction.... could be a wobbly hot end that isn't attached firm enough.

I am happy to report that I am now (after lots of other tinkering) getting pretty amazing looking prints with perfectly aligned layers!

Hope that helps....

get metal pulleys on x and y axis not alot of money should be some on ebay

i had the same problem on the x axis just added a 8cm fan straight on to ramps board that cured it hope that helps

I also had this problem but traced it to the fact that my idlers which were printed from thingiverse were slightly acentric. The 'z-blob' meant that when as the idler turned the belt ternsion was changing. Every time my idler went past that point the motor tended to miss steps, but only in one directiion.
diagnostic was to sit the axis at 10mm from zero, then move forwards 100mm and back again. Each time it returned to a point a few mm closer to the origin than the last.

Replacingthe printed idler with a pair of fender washers and a bearing solved this for me a lead to a less noisy printing process too.

took ages to figure out though - had to stare at the belt as it moved for a long timebefore it becase aparent what was going on.