Hello folks! Build a MK4 4 months ago and was very happy with it so far. Now I have bed adhesion problems (see pic attached). 3 weeks ago I had similar problems and after a chat with prusa and resetting the calibration / cleaning the build plate again it worked fine. Now the problem is back despite a clean build plate . After resetting the calibration I got one nice print and then the same problem again. Cold pull of the nozzle resulted in a clean tip and no better results, so I do not think there is any clogging. Also the plate and the should be alright, as I got good results inbetween. Any ideas / hints where my problem is? Link leads to image of the problem. Could not upload the file for some reason…
Thanks, will clean it again, this time as you suggested. Usually I use the isopropanol on the cold plate.