first three layers show increasing offset in Y

[tomnagel 126]

My Ultimaker is less than 3 weeks old, so I have little experience yet.

I did make some ok prints, but the last three object all show a strange phenomenon: the first few layers show an increasing offset in Y direction, so when I look at the object from the side of the Ultimaker, the side of the object should be perpendicular to the print bed, but it looks like a stairs.

To be very specific: layer 2, 3 and 4 each shift around 0.2mm (one wire thickness) w.r.t. the layer below. After that, layer 5 and further are perfectly on top of each other.

The first time this happened I had increased printing speed to 75mm/s, and I assumed the Y-stepper had lost some steps in the first part of the print. But it is reproducable, also with speed back to 50 mm/s.

I have been editing the start-Gcode to lift the printbed a bit after homing the Z-axis (which by the way didn't work). I don't see any relation to my problem, but maybe there is.

Any help is appreciated.

[Daid 306]

It's called "layer shifting" and while right now you have it on the first few layers, it could happen on any layer. What you should check is:

* Does the Y motor have enough power

* Are your pulleys firmly attached to the rods

* Are both your long AND short belts tight

It could also be that your start height is too low, and that the head moves into the first layers during the print of the next layer, but this usually also results in other problems.

[giraffneck 0]

I am relatively new to this, I bought an ultimaker original that was a few years old from somebody and put the newest version of the electronics in (1.5.7), I also upgraded the extruder and hotend. It prints small objects perfectly every time, but when I tried to print a larger object every layer from the start of the print to the end slides down the y axis (about .5mm) each layer. I have tightened the drive belts, lubricated all of the shafts, and tightened all of the set screws, reinstalled the firmware. I don't understand what else it could be and it doesn't make sense to me that its only on prints that take up a large portion of the bed. Any advise would be greatly appreciated.

 

[blahbla 0]

I'm seeing the same thing as you giraffneck and have tried tightening belts and lubricating. The ultimaker robot print works, but with bigger prints gets skewed. Did you fix your problem?