2
$\begingroup$

I left my printer to print a circular object and when I came back I saw it didn't print anything but left this layer of white on the surface. I can't get it off, I've tried washing it and scraping it off with the chisel, nothing works.

Printer bed with white circular marking

$\endgroup$
1
  • $\begingroup$ Does it effect print adhesion? Might just be a mostly cosmetic issue, trying to clean it may just cause more damage. $\endgroup$
    – Kezat
    Sep 10 at 16:21
7
$\begingroup$

My guess is it's damaged print surface from the hot extruder mashing against the print surface. Your description seems to indicate that it isn't a layer.

$\endgroup$
1
  • $\begingroup$ I'm inclined to agree with @Perry Webb: That looks like heat damage $\endgroup$ Sep 10 at 15:04
2
$\begingroup$

If it actually is residue from the material you were trying to print, pressed against the surface so tightly and so thin that you can't separate it, the best way to remove it is printing a new object on top of it, using the same material, with the bed properly leveled (i.e. not smashing the nozzle into it again) and with the bed and nozzle temperature high. If things go well, it will then come off with the print when you're done after the bed cools. This is because printable thermoplastics tend to stick better to themselves than to the bed.

$\endgroup$
5
  • 2
    $\begingroup$ I have similar marks on my print bed from when I was learning the proper way to level the bed. It has not harmed my prints but it just doesn't look right. $\endgroup$
    – agarza
    Sep 10 at 22:26
  • $\begingroup$ @GitHub While this is true for most filament materials, it is not true for PETG. $\endgroup$
    – Perry Webb
    Sep 13 at 12:04
  • $\begingroup$ ABS scrapes off best with the bed hot, but this will distort a print. $\endgroup$
    – Perry Webb
    Sep 13 at 12:09
  • $\begingroup$ @PerryWebb: What happens with PETG? It adheres better to the bed? I think it might work with PETG if you get the bed really hot -- in my experience, PETG can be difficult to get adhesion between the first and second layer because the bed sinks too much heat out of the material for it to bond well. If not for that, I'd print PETG on a fully unheated bed. $\endgroup$ Sep 13 at 13:12
  • $\begingroup$ @GitHub The trouble with 1st and 2nd layer adhesion with PETG is usually caused by the initial z-height being slightly high to keep PETG from sticking too well to the print surface. If the initial z-height is slightly low without an extra print surface such as a glue stick layer, PETG can stick so well to the print surface that it rips holes in the print surface. Heating the bed might help. I would try printing the PETG at room temperature, then heat the bed to get a thermal mismatch for removal. Of course, this is backwards from getting a good printed object. $\endgroup$
    – Perry Webb
    Sep 13 at 13:40

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.