No extrusion - etching on printer bed

When I started a recent print with PLA, the filament stopped extruding almost immediately and the bed became etched in the pattern the hot end followed until I stopped the print. Its not deep, but is enough that the pattern now appears on the bottom of everything I print.

Is there a way to remove this, short of buying a new bed? is there something I needed to do to prevent it in the future? I’m still new to this but followed the instructions as I’d done on previous successful prints, and verified the printer was up to temperature extruding OK before I started the print.

Thanks for any advice or recommendations.

I had the same thing happen to me, and am also curious about the best way to go about repairing it, as well as prevent it…

Although my printing has of yet, needed PLA, but I’ve stayed away from PLA just because of the clogging issues I’ve read about with LB’s…

I would guess that mine happened when my hotend “clogged”, or in better terms “hydro-locked”… and the knurled bolt dug into and carved away at the filament…

Weird because it was with ABS… To fix it, I heated the hotend as hot as it would go… Pulled the old stuff out, cut about a foot off the reel I was using, and fed a butt-ton of filament through it…

I’ve since finally landed some E-Sun cleaner filament<-- seems gimmicky to me, but whatever… I’ll give it a go…

The beds I have ran across with the PEI plastic ‘etched’ like that I have had to pull the old PEI and clean off the adhesive then reapplied a new sheet of PEI on the clean glass plate. The nozzle kind of puts the groove into the adhesive also while damaging the plastic sheet.

So just replacing the PEI leaves the grove in the adhesive which will still show underneath, but may be good enough to not show up on the parts. But I have found that the adhesive damage tends to cause the sheet to not adhere very well anymore there.

Sounds like a a Z-Axis problem to me. Have you made sure your z-axis is level on both sides?

Try a fine grit sandpaper to get gouges out. Make sure to sand in long strokes to keep the eveness of the bed.

For reallly fine marks try a Mr.Clean Magic Eraser… also good to revitalize / remove oil.

Anytime you have a too small first layer height on the LulzBot Mini it is due to the nozzle being dirty/excess plastic remaining on the surface of the nozzle. During the homing/bed probing process it is pushing through the plastic on the nozzle so the Z0 it establishes is lower than it actually is. Nozzle cleanliness is the key for great prints on your LulzBot Mini.

Heat up your hot end and wipe off the nozzle with a clean dry cloth. Contact our Support Team at Support@LulzBot.com for information on your PEI bed surface.

I’m thinking that it’s time to EBay this Mini, and move on…
The more I print with it, the worse it gets… and being a super-duper nerdy 3D printer/hobbyist, is NOT what I’m after… :smiley:

Good luck… I’m tossing this one as a bust!!! What really sucks, is that I spent a good dime on 3MM filament, that I’ll have to take a hit on trying to sell(not many printer use it) :cry: