Damaged or worn PEI sheet: causes, care and replacement

This guide is for anyone looking at a build plate with a torn patch, gouges, a dull shiny area or grip that's faded. It covers what Prusa, Bambu Lab, Creality, BIQU and Polymaker say damages a plate, which marks they call normal, how each maker says to clean and restore its own plates, and when they say to replace them. Each maker's advice applies to that maker's plates. If you're dealing with a print that won't come off right now, start with our other guides:

Damage or normal wear?

Check this first, because several marks that look bad are ones makers call harmless.

• Bubbles under smooth PEI (Prusa). Prusa says these are "nothing serious," that they "usually do not affect print quality and will disappear after a few days or weeks." They form where you print most, "most often underneath the corners of your printed parts." Prusa suggests swapping to the other side of the sheet and varying where you place prints.
• A dent in new smooth PEI (Prusa). Prusa says to flip the sheet and use the other side, and that the dent "will disappear by itself" after about 1 to 2 days of print time.
• Wear in the wipe zone (Bambu Lab). On the X1C, P1S/P1P and A1, Bambu says the nozzle touches the plate in a wipe area, so some "wear" may show there, and that it "does not affect the functionality of the nozzle or the build plate." Bambu says the A1 mini wipes on the heatbed instead, so its plates don't get this.
• Wear at the rear wiping area (Creality SPARKX i7). Creality says the raised rear section of the i7 plate is the Fine Wiping Area, and that coating wear there after long use "is considered normal."
• Marks and discoloration (Bambu Lab and BIQU). For the Cool Plate SuperTack, Bambu says a few persistent stains or first-layer marks "are normal and do not affect long-term use or performance." It says faint marks on the Engineering Plate are normal too. BIQU says minor discoloration or first-layer imprints on CryoGrip Pro that can't be fully removed "do not affect long-term performance."
• Light scratches on soft coatings (Bambu Lab and BIQU). Both say the Cool Plate SuperTack and CryoGrip Pro coatings are softer than textured PEI and scratch more easily, and that minor scratches from normal use won't significantly affect adhesion.

Real damage looks different. Prusa's guidepost describes a removal where "a piece of the surface was ripped off or cracked." Polymaker's troubleshooting table lists textured PEI that is "gouged or pitted." Bambu warns that glue that grips too tightly can make a sheet "bubble or crack."

What damages a PEI plate?

On removing prints, Prusa says to "always wait until the steel sheet cools down to room temperature," and for its Textured PEI Plate, Bambu recommends waiting until the heatbed reaches 35 °C or lower. Prusa ties a ripped or cracked surface to the filament and preparation: "you might be using a filament type that is not suitable for being printed on this kind of print sheet or the surface was not prepared correctly." Our print stuck to the bed guide has the step-by-step removal methods.

Cleaning and restoring, maker by maker

Prusa says grease stains "often cause poor surface adhesion," so clean the plate the maker's way before deciding it's worn. Prusa also says "Any grease will greatly reduce adhesion," and Bambu says skin oils "reduce the plate's adhesion to filament." Our print stuck to the bed guide also covers how cleaning changes grip.

Prusa smooth PEI sheet

• Routine: "Clean with ~90% IPA (isopropyl alcohol) or denatured alcohol when cold," on an unscented paper towel. "Do not use anything made for skin!"
• Deeper clean: acetone in the same way, "1-2 times a month," if IPA isn't enough.
• Restore: Prusa says that after 1 to 2 years "the surface can smooth out further, which affects adhesion." Light sanding with 600 to 1000 grit paper brings "fresh PEI to the surface," and the sheet "will have a very light texture after this treatment."

Prusa textured (powder-coated) sheet

• Routine: ~90% IPA or denatured alcohol when cold.
• If prints still won't stick: wash it in "warm water (not hot!) with a few drops of liquid dish soap (not hand soap)." Prusa says the sheet "is not waterproof," so treat this as a last resort, and don't submerge it completely in hot water.
• Don't: use acetone, ABS juice, metal spatulas or the freezer.

Prusa's textured sheet article doesn't describe sanding. Its first-layer issues guide has a "Resurface it" section for shiny marks left by the nozzle or tools, which it says don't affect adhesion: gently rub with the hard side of a dry kitchen sponge or 400 to 600 grit sandpaper, then wipe with IPA. That section doesn't say which sheet types it applies to.

Bambu Lab Textured PEI Plate

Bambu recommends "a basic sponge and dishwashing detergent, rinsing it with warm water, and drying it with a regular paper towel." It says a scouring pad or plastic brush reaches "into the grooves of textures," and that alcohol "might just spread the oils" on a textured surface. Use a detergent with no oils or moisturizers.

Bambu gives a quick check for whether the plate is clean. Before cleaning, water on the plate "flows down in streams and gathers into droplets," which indicates poor adhesion. After cleaning, it "forms a thin water film."

To restore it, Bambu says: "Grinding the surface of the Textured PEI plate with fine sandpaper or steel wool will create a new, clean surface and enhance the build plate's adhesion." Clean off all the sanding debris afterwards.

Bambu Lab Cool Plate SuperTack and Engineering Plate

Bambu says most marks on both come off with alcohol wipes, or detergent and water. For a print that grips too tightly on either, it suggests applying alcohol where the model meets the plate before lifting it with a scraper.

Creality SPARKX i7 plate

Creality's page covers the dual-texture gold PEI plate that comes with the SPARKX i7. Wet it with warm water, scrub with dishwashing liquid and a scouring pad or soft brush until it foams, rinse, and dry with paper towels. Use a detergent without oils or moisturizers, and hold the plate by its sides. We didn't find an equivalent Creality wiki page for its other plates.

BIQU CryoGrip Pro

BIQU says to clean Frostbite "with soapy water" and Glacier "with alcohol or soapy water." Most residue comes off with alcohol or soapy water.

When should you replace a PEI sheet?

• Prusa smooth sheet: Prusa says the PEI film "can be replaced in case of extensive damage."
• Prusa sheets in general: Prusa treats sheets as consumables. Its warranty covers only sheets defective on arrival, not coatings that "diminish over time" or cosmetic damage such as "scratches, dents, cracks."
• Bambu Lab PEI and SuperTack plates: Bambu says its Textured PEI Plate, Cool Plate SuperTack and Smooth PEI Plate "do not support the replacement of spare sheet." The Smooth PEI Plate's sheet is stuck on with "a highly heat-resistant 3M adhesive, making it difficult to remove." Bambu calls its plates a consumable part that may need replacing if damaged after extensive use.
• Bambu Lab High Temperature Plate and Cool Plate: Bambu says only these two take a replacement sheet, and both have been discontinued.
• Creality SPARKX i7: "After extended use, PEI print plates may experience irreversible adhesion degradation. In this case, adhesive can be applied, or the print plate can be replaced."
• Polymaker: for gouged or pitted textured PEI, it says to "replace sheet if damaged."

If you're replacing a sheet because PETG or TPU tore it, change the setup too. For PETG, Prusa recommends "another type of steel sheet or adding PVA glue as a separation layer," and our bed adhesives guide covers what each maker says to use. Our PETG printing problems guide covers PETG-specific fixes, including prints that tear a smooth PEI sheet.

Choosing a replacement that fits

A plate only fits if its maker names your exact printer model. Our build plates shortlist lists plates by printer, using only the compatibility records we hold, each tied to the plate maker's own fit statement. If your printer isn't listed there, check the plate maker's compatibility list for your exact model before buying. For BIQU's two coatings, see CryoGrip Pro Glacier vs Frostbite.

On Prusa printers without a loadcell, Prusa says each sheet type needs its own Live Z value, because the sheets "have slightly different thicknesses." Recalibrate the first layer or set up a sheet profile when you switch.

Checklist

• Damage, not just bubbles, a dent, wipe-area wear or harmless marks.
• Cleaned the maker's way: IPA, detergent or soapy water, depending on the plate.
• No acetone on a plate whose maker forbids it.
• No metal spatulas on textured PEI, and scrapers used carefully on soft-coated plates.
• Separation layer for PETG and TPU on smooth PEI, and for PET or CoPE on textured PEI if your filament maker asks for it.
• Only materials the plate is made for.
• Worn surface restored only where the maker documents sanding.
• Replacement checked against your exact printer model.

How this guide was checked

This is a research-based guide. We haven't damaged or restored plates for it. Every cause, cleaning method, restoration step and replacement rule comes from the Prusa Research, Bambu Lab, Creality, BIGTREETECH (BIQU) and Polymaker pages listed in the sources, retrieved on 2026-10-12 (the first-layer issues guide on 2026-10-13), and applies only to the plates each page names. Plate fit comes only from our compatibility records. Read more in our editorial standards.

Build plates: what to check before you buy ↗