Y osset issue second layer

[NicolasVINCENT 0]

Hello,

 

When I print with the 2 extruder (PLA + PVA), there is a Y offset issue on the second layer (red line on the photo). All the time.

 

When I print with only one extruder everything is OK.

 

Someone can help me?

 

Thanks,

 

(ultimaker 3 extended)

[gr5 2,097]

I think your Y axis slipped.  I have two theories:

1) Usually this happens when the pulley slips on the rod.  So test this with a sharpie (permanent marker).  Mark the shaft and pulley of all 6 Y axis pulleys - most importantly the two on the short belt which is on the stepper.  You may have to remove the cover to get at the Y axis stepper but if you have a long hex driver you can push the print head around until you have a clear view of the pulley set screw.  Tighten those very very tight.  So tight you are afraid you will break something.

 

@fbrc8-erin - how much torque do you tighten those with?

 

2) This could be that when it switches to the other head it isn't in the right position (the nozzle changer device on the side of the printer) and it pushes so hard against the nozzle changer device that you loose Y steps.  This should be obvious if you watch this happen.  There is a calibration procedure to check this but I'm told it is tricky and should only be attempted as a last resort.  I would instead rule out this #2 theory by rebooting the machine and then changing back and forth between the 2 nozzles using the menu system.  It's probably #1.  

[NicolasVINCENT 0]

issue sloved!

there was a big misalignment of the axes