The hotend is scraping the bed

QuestionsCategory: Printing and calibrationThe hotend is scraping the bed
Frode asked 9 months ago

I have a problem with the hotend, as its scraping the bed when I try to print. And the layer fan is toutching the tool rod.
I follow the calibration to the point, but still it goes to far. The sensor for the hotend is placed so that the red light comes on when its in the perfect position when I do the G28 command.
But when I start printing, the hotend moves down slightly and touches the bed.

1 Answers
diegotrap Staff answered 9 months ago

I think this is an issue relating to the Z probe offset value. We have been researching this and the proper value of the offset may differ greatly from the value obtained with the theoretical procedure that we currently suggest in the M Prime One first print guide.
So what you are experiencing is normal, you’ll have to adjust the Z offset value in a trial-and-error fashion.¬†Since you have already a value that results in the hotend tip being too low, try a more positive value (we have found that the offset can be positive too). Maybe start with +5 or +10mm, which will make the hotend tip to “fly over the bed” and then reduce the value until the plastic is deposited just above the bed.
Currently that’s the best way to get the Z offset, sorry for the inconvenience..