First layer issues - calibration problem , firmware issue or something else
Hello,
Apologies for the longer than needed text, I just want to put down all info I have.
I've had my MK4 (kit) since the start of this year ; it's barely used (5 hours or print). I am recently running firmware 6.0.0 and when printing a keychain I saw a pretty bad first layer in the center of the printbed ; the keychain came out OK so no problem - I have been having issues with nozzle cleaning errors having to constantly redo the nozzle clean (more on it below, I just found out when coming to the forum that there was a bug in 6.0.0 related to it).
Additionally I sometimes did only some (a subset of the total) calibrations of the printer from the menu ; the printer kept asking me on every bootup (and I think before every print) to finish the calibrations ; because I had done them fully and successfully once after assembly, I ignored these warnings.
I tried printing a bed level test from printables. First problem was that during the sample points phase (when the loadcell is used), before actually printing, the nozzle was suddenly pushed (it appeared to me very forcefully, the fan shroud seemed to bend once under force) into the build plate. You can see a darker line in the picture below where that happened and the nozzle was then dragged along the print sheet. I stopped the print as soon as I could. I had no idea what could be wrong so the only thing I could think of was to completely redo the calibrations. I did that and then had a successfully completed print.
First layer test 1:
I think the right 2 columns look relatively ok, maybe the nozzle is a bit too low but I don't think they are bad. The left most column looks pretty bad.
As I was coming here to ask what could be wrong, I ran into a forum post describing the fact that firmware 6.0.0 has a bug with nozzle cleaning and loadcell usage. I updated to 6.0.2 and without any other change i printed the model again (same bgcode as above, same filament - rPLA, same settings, the build plate had been washed and dried before the first test).
First layer test 2:
This looks even better, still a problem in the upper left side but definitely better. So I'd like to get an even better print but honestly, It doesn't look that bad in my inexperienced opinion. Maybe the nozzle is too low there again? Maybe it's an assembly issue. Any tips on what to try?
I am actually more worried about the nozzle being forced into the printbed? Did that happen to other people? Is it something I should check on my printer after that event? I see no bad behaviour after (both prints linked here are after that happened). It was pretty .. intense I guess ; just looking to see if that is common, if it could've been because of firmware 6.0.0.
Thank you very much for taking the time to read this.