ABS residue on printer bed - can't remove with acetone

Hi all,

I’ve printed two small models with ABS on our office LulzBot Mini, and some residue was left on the printer bed.
I tried removing it with acetone, but even after some thorough soaking & rubbing, some still remains:

When I touch the bed it feels completely smooth, ie. this is probably a super thin layer of residue.
My questions:

  1. How can I clean the bed better? Is there a stronger material than acetone, or perhaps something I’m doing wrong?
  2. Is it safe to print over this tiny layer of residue?

Thanks!

Try a green scottbrite pad with isopropyl alcohol. Also try scraping off with a metal spatula type tool.

Its fine to print over it and hope it comes off with the next printed object.

If it is smooth to feel I do not think it is residue, its likely air bubbles under the PEI. How hard was the print to remove and what temperature was bed when print removed

Be very careful if you use acetone on a PEI sheet, it can eat through it. Next time you should try 9 parts water to 1 part alcohol, it works great for cleaning the PEI sheet, without having the risk of eating through it. You can even use the water/alcohol mixture with some 2000 grit sandpaper to wet sand the bed and it help prints adhere better to it, just make sure that you wipe it off good after doing the wet sanding.

Obviously you don’t need to get prints to stick better though. :smiley:

PEI (Ultem) really isn’t eatable by Acetone. http://www.astisensor.com/ultem.pdf There is a slight risk of crazing on the surface due to heat differential if you apply cold acetone to a warm bed, but otherwise it basically won’t do anything at all to PEI.