Hey there… I think this is the PERFECT time for me to step in. I have a great page of information from top 3d printer brands in how to clean PEI plates. I will link the document for you. Just so you know, the document was specifically who used GLUE way too much, and you build plate looks to be in much much better condition than his.
Official Bambu Labs Recomendation
https://wiki.bambulab.com/en/filament-acc/acc/pei-plate-clean-guide
We recommend cleaning the printing surface with a basic sponge and dishwashing detergent, rinsing it with warm water, and drying it with a regular paper towel.
The reason why we recommend detergent for cleaning the textured plate is due to its textured surface. Alcohol might just spread the oils on the print surface instead of removing it. Detergent acts as a degreaser and using a sponge or scrubber to wash the plate will ensure the detergent reaches inside the textured surface to clean it and improve adhesion.
After applying the dishwashing detergent to the Textured PEI plate, it’s important to scrub it with a sponge or a brush to completely remove any leftover models and grease.
Also make sure that you avoid touching the print surface with your fingers and try to handle the plate from the sides.
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Official Creality Store Recommendation
https://store.creality.com/blogs/all/how-to-clean-3d-printer-bed
Start by letting your printer bed cool down. Once it’s safe to touch, use a scraper or putty knife to gently remove any bits of filament or debris that are loosely attached to the bed.
Then wipe down the entire surface of the bed with isopropyl alcohol to remove any oils, fingerprints, and leftover residue. Use a soft sponge or cloth with dish soap to gently scrub the surface. Rinse it thoroughly with warm water and dry it with a clean cloth.
If you handle the bed, try to do so with clean hands or wear gloves to minimize transferring oils to the surface. For PEI surfaces, avoid using acetone as it can damage the material. Stick to isopropyl alcohol for routine cleaning.
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Official Prusa Research Forum Recommendation
https://forum.prusa3d.com/forum/original-prusa-i3-mk3s-mk3-hardware-firmware-and-software-help/pei-bed-cleaning-methods/#post-141005
Consumer-grade solvents won’t break grease down completely, just enough to ease removal. Unless you’ve both broken the grease down and physically removed it, adhesion will remain poor.
Hot water and dish soap are FAR more effective for the following reason. Volume. There’s just so much more soap and water being used to wash and rinse that it is more likely to break down grease sufficiently and wash it away.
Soap is a surfactant and causes material to lift from surfaces. Water acts to dilute the soap and rinse soap and lift material away.
Hot Water wash: Handle the bed only by the edges. Wash the bed in hot water, use a fresh paper towel as a wash cloth, with a few drops of plain dish soap (Dawn, unscented, no anti-bacterial, etc.). Rinse well in hot water - if you have very soft water, rinse a bit longer. Dry the bed with a fresh paper towel. Handle the bed only by the edges.
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Official Additive+ Recommendation
https://additiveplus.com/how-to-clean-your-3d-printer-bed-and-remove-3d-prints/?srsltid=AfmBOoofD7oLWaYF_ZwwG0dsqJF0JMzXMaztGMhtPRHeiionxzNplXRs
Polyetherimide (PEI). Strong, durable surface, works well for lots of filaments. Sensitive to IPA/acetone
PEI should not be exposed to harsh chemicals or IPA and acetone at all often. Instead, wash thoroughly with warm water and soap. Make sure to NOT touch the build plate after washing it, as it will get oily fingerprints back on it.
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Official Snapmaker Recommendation
https://www.snapmaker.com/blog/how-to-clean-your-3d-printer-bed/
Warm Water & Soap: In cases where the stains are tougher or have heavier residues, warm water with mild dish soap usually helps. The bed should be rinsed and dried thoroughly before use. Don’t soak parts attached to the printer.
PEI-coated surfaces are sensitive to oils and fingerprints, so avoid touching them directly after cleaning.
IPA is fine for general cleaning, but when using it to clean with low adhesion, you might as well wash it in warm, soapy water. Use acetone only occasionally to revive it. The more you do this, however, the more the sheet will degrade.
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Official Sovol Recommendation
https://www.sovol3d.com/blogs/news/how-to-clean-build-plate-safely-easy-steps-3d-printer?srsltid=AfmBOorICS-EAXXbVGvAvUnNZK0cXfJ4V8SQWo8yBohfTPPoGCHk4k_6
Warm water and a mild detergent soap make a safe cleaning solution for most build plates.
Use a basic sponge to spread the soap. This helps break down oils and leftover glue. Rinse the plate with warm water after you clean it. Make sure your soap does not have oils or moisturizers. Avoid acetone. It can damage PEI surfaces and other coatings.
If you notice stubborn spots, let the plate soak for a few minutes. This helps loosen up any stuck-on material. Remember, specialized cleaners can sometimes work better for tough stains, but plain dish soap is safe and effective for regular cleaning.
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Resources
https://www.youtube.com/watch?v=Hp9YtXFFOMQ&t=2s
https://www.gambody.com/blog/helpful-tips-for-cleaning-your-3d-printer-bed-pei-glass-magnetic/?srsltid=AfmBOooSm15dl4cDTIe-9
Rv1HWBotsjRyb_tZ6p-3dbEw9JYfr-3gpvw
https://www.eufymake.com/blogs/maintenance-guides/how-to-clean-3d-printer-bed
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In closing, it seems to be widely agreed upon that glue should only be used when you don’t have a specialized print bed, when the print bed is low quality, when the print bed is of a CERTAIN material, or when printing objects from materials that adhere much too well or way too little. (Nylon and TPU)
Acetone seems to be looked down upon by most, and should probably not be used at all. Isopropyl alcohol has proven itself to be a good way of ‘loosening’ difficult grease marks, but overtime it harms PEI plates.
Washing the plate reasonably often, (three-five times per month) is overall the most agreed upon way to have incredible adhesion, super good first layer quality, and unharmed build plates.
Too much glue, (more than a thin sparse layer after a wash), has proven itself to lead to WORSE adhesion, WORSE print quality, unstable printing environments, and crusty build plates.
Solution? If you MUST use glue, use it sparingly and wash the build plate often. But it’s not necessary! By not touching the build plate with bare hands at all, by buying an enclosed printer to reduce dust, and by not using glue, you will succeed in having the best of every world.
NO YES
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