My ender3 came with a BuildTak-clone surface, and as I was a little too vigorous in getting the print off the bed (I had failed to level right and printed a bit too tight to the bed, resulting in SUPER strong adhesion), I needed to replace it.
Peeling off the black was easy. The plastic sheet that held the glue was easy too... but how to clean up the bed to get the residue glue off and prepare for the new 3M sticker?
In my experience, we deal with 3M™ Adhesive Transfer Tape 468MP; high-temperature glue residue. To remove the leftover glue from my Aluminium build plate I found that it works best if I apply paint thinner.
I ran out of acetone for one refurbishment so I tried thinner and white (cleaning) spirit; the latter option did not work well. However, thinner worked very well. I got a bottle of "thinner" at the hardware store's house brand and found it to be more aggressive stuff than turpentine or acetone. I had tried those latter 2 but found that "thinner" works best.
Putting the thinner fluid on paper cloth directly to clean the glue did not work well. I applied the thinner directly onto the glue (splash it on), waited for a while to let it soak in to weaken the bonds after which you can remove it with a spatula and kitchen paper towel.
The exact contents of paint thinners are not always available but they contain various hydrocarbons.
Cleaning up the aluminium build platform was rather easy in a three step process as I figured out:
Get the old bed-surface off and any film layers that stick to the original glue. Don't bother to try to scrape off the glue, it is wasted time.
To remove the sticker's residue, I first tried heat and 70% isopropyl alcohol (aka isopropanol, 2-propanol), which was not very effective.
What did prove effective was nail-polish remover on the base of acetone. It worked like a charm to turn the sticky film into easily removable, goopy clumps. With small doses and a lot of rubbing/massaging it into the residue and careful use of the scraper, all the glue was gone after about half to three-quarters of an hour of work.
In subsequent replacement, I used paint thinner, which is more effective in goopifying the glue and allowing to scrape it off much faster. 10 minutes max.
After applying the generous amounts of nail polish remover, I thought that it might be best to get any of the additives that were meant to protect the skin off the bed - as well as the slight blue coloring - before applying the new tape. So I gave the aluminium a good wipe down with isopropanol.
In subsequent replacements I used ethanol 98 % to clean the bed before applying, just to make sure no fingerprints or glue residue creates bumps.
Applying the new bed surface was easy afterwards, and after a quick bed leveling, the printer runs like a charm again.
Following up from Charles Duffy's comment, I can confirm that adhesive remover containing D-limonene is an effective way of removing remaining glue when replacing an Ender-3 platform sticker. While “Goo Gone” was named in the comment, I used a similar product, Goo Buster.
Goo Buster turned the glue residue into a water soluble gel that was easily removed using a plastic scraper, with final clean up using a wet paper towel. While D-Limonene has a pleasant citrus fragrance, it is an irritant, and these adhesive removers typically also contain petroleum products and surfactants.
As ever, use care when using solvents near electrical devices such as 3D printers. Ensure the device is isolated from power and all parts are clean and dry before operating.
