Issue With Print Bed
Hello,
New here with an MK3S+. After my 2nd print, some descoloration appeared on the print bed sheet. Looks like bubbles and they are slighty raised.
Default PLA settings (bed temp and nozzle temp) Bed cleaned only with Isopro. Alcool and part removed after bed was cold.
What it is?
Thank you
RE: Issue With Print Bed
If I had to guess, your print head crashed into the smooth sheet multiple times and places repeatedly, perforating the PEI sheet. Second guess would be a thick glass vase fell on your print bed and shattered, leaving cuts in the smooth PEI
RE: Issue With Print Bed
@dan-rogers
Thank you. I watched first layers and they went ok. The bubbles are inside the PEI sheet. You can feel the bump but there is no scratch.
RE: Issue With Print Bed
Bubbles under the smooth sheet can be managed. Take a plastic spatula/scraper and "iron" your bubbles, pressing the PEI sheet back onto the glue. Then heat it up (preheat) and iron it some more with your scraper - the bubbles should re-adhere to the underlying glue layer.
Were you previously printing something with PETG by chance? Those bubbles can be the result of peeling a print off the sheet and not having used an appropriate release agent for the material you used. If you're lucky the sheet isn't perforated (that picture sure does look like pits to me)
To avoid over-adhesion causing this kind of release-stress on your smooth sheet - for PETG use windex. Spritz some on while the bed is relatively cool, wipe it off with a paper towel, and do your print. It'll come of a lot easier and usually won't separate the PEI sheet
RE: Issue With Print Bed
@dan-rogers
Hello, i will try.
I only made 5 prints and all of them with PLA. The printer is brand new and it happened at the base of the large prints. The print piece came out perfectly after the bed cool down or with no force at all, but those bubbles appeared.
Thanks for the reply.
RE: Issue With Print Bed
If it's a new printer, you could try and convince Prusa support to replace it, but they probably will not since this is considered a wear part. Were those holes there before your big-surface print? If you can still print on it - consider this side your first "spare". Turn it over.
I'm on my 3rd smooth sheet - and now I stack them up when I ruin them (have learned to avoid ruining new ones though) - and you can order the replacement surface from Prusa online shop - log in with your registered account and they are in the spare parts section. There is a nice article that and instructions that come with the replacement PEI sheet - but it's a messy job to do outside with gloves and a respirator.