Bed Adhesion: How Six Methods Work and Where Each One Fails

Bed adhesion advice is mostly inherited. Everyone has a method they trust, and most of the trust comes from the fact that it worked the last time rather than from knowing why.

The useful way to sort these six methods is not by a league table but by mechanism: what actually holds the first layer down, and what makes that mechanism let go. Once that is clear, picking one for a given filament stops being guesswork.

The one that beats all six

Before any of this: a correctly calibrated first layer outperforms every adhesion aid on this page. A Z-offset even 0.05 mm too high undermines all of them equally, and no amount of glue compensates for a nozzle that is not pressing the first layer into the surface. If you have adhesion trouble, run a first layer calibration before you change anything else. Our first layer guide covers the procedure.

How the six actually work

Textured PEI

The modern default, and the reason most printers now ship with it. Adhesion is mechanical: the filament flows into the texture and keys into it, then lets go as the plate cools and the two materials contract at different rates. That is why a print that will not budge at 60 °C often pops free on its own below 40 °C. Waiting is usually better than levering.

Its one real weakness is the opposite of a weakness elsewhere: PETG bonds to PEI hard enough that over-squishing the first layer can tear the sheet surface when you remove the part. Raising the Z-offset by roughly 0.02 to 0.04 mm for PETG compared with PLA keeps adhesion reliable while leaving a releasable bond. The PETG bed temperature guide has the rest of the settings.

Smooth PEI

Same chemistry, different surface. It gives a mirror-smooth bottom face, which is worth having on display pieces, and it has less margin than textured PEI on exactly the filament that already needs margin. For PETG on smooth PEI, a thin layer of glue stick is the standard answer, and it is worth understanding that it works as a release agent here rather than an adhesion promoter: the PVA is a sacrificial barrier between the PETG and the sheet.

Magigoo and similar adhesives

A purpose-made product that bonds while the bed is hot and releases as it cools. Its appeal is consistency across materials: if you switch between PLA, PETG and ABS regularly, it removes the need to change strategy for each one. The costs are real, around fifteen dollars a bottle and reapplication every few prints, so it earns its place in a multi-material workflow rather than on a printer that only ever runs PLA.

Glue stick on glass

The budget classic, and still perfectly serviceable for PLA. The weakness is consistency rather than strength: application thickness varies by hand, and adhesion varies with it. Too thin and the part lifts, too thick and the bottom surface comes out rough with residue.

What glue cannot do is counteract warping. On ABS it holds the first layer while the part above contracts, and contraction wins.

Hairspray on glass

It works, and it is the least pleasant option to live with. The film builds up unevenly over a few prints, the buildup attracts dust, and restoring a clean surface takes more effort than wiping PEI with isopropyl alcohol. There is also the matter of aerosolising a sticky polymer near a printer's electronics and fans. If you use it, take the plate off the machine and spray it somewhere ventilated.

Blue painter's tape

Genuinely obsolete on a modern machine. Adhesion to PLA is fine, but the seams between strips print into the bottom surface, the tape itself can lift from the glass mid-print, and it needs replacing constantly. It solved a real problem in 2018. A spring steel PEI sheet now costs about the same as a few rolls and solves it permanently.

Keeping the surface working

PEI loses adhesion for one reason far more often than any other: skin oils. Handling the plate by its face transfers enough grease to create a patch where nothing sticks, and that patch stays until it is cleaned off. Pick the plate up by the edges, and wipe the surface with isopropyl alcohol every few prints rather than waiting for a failure.

Alcohol handles oils but not PLA residue baked onto the texture over months. For that, warm water with a little washing-up liquid and a soft brush restores the surface, as long as it is dried completely afterwards. Avoid acetone on PEI, and avoid anything abrasive on smooth PEI in particular, since the finish is the whole reason to own it.

A textured sheet that has genuinely worn smooth in the middle, where most prints land, is consumable rather than broken. Many are coated on both sides, so flipping the plate buys a second life before it needs replacing.

When adhesion is not the problem

Three failures look like bed adhesion and are not, and chasing them with glue wastes time.

• Corners lifting on large prints only. That is contraction, not grip. The fix is an enclosure or a draught shield, not a stickier bed.
• The first layer looks fine but the part shifts later. Usually a belt or a loose part cooling fan knocking the model, not the surface letting go.
• Adhesion that is too strong. A part that needs force to remove, or that takes a chip of the sheet with it, is a calibration problem in the same family as a part that will not stick. Both come from the wrong first layer height.

What to use for which filament

• PLA: textured PEI at 60 °C, nothing else. Wipe with isopropyl alcohol every few prints and it stays reliable.
• PETG: textured PEI at 80 °C with the raised Z-offset above. If it still bonds too hard, add glue stick as a release layer.
• ABS: textured PEI at 110 °C, inside an enclosure. Without one, no adhesion method reliably prevents warping on parts much over 50 mm, because the problem is contraction in the part rather than grip at the bed. See the enclosure guide.
• TPU: textured PEI at 60 °C and a slow first layer, around 15 mm/s. TPU sticks to almost anything, so speed and retraction settings matter more than the surface does.

Bottom line

If you are buying or upgrading, get a textured PEI sheet. If your printer still has a bare glass bed, a spring steel PEI plate is a fifteen to twenty dollar upgrade that removes most adhesion problems outright.

And keep the order of operations in mind: calibrate the first layer, then clean the surface, then consider an adhesion aid. Most of what gets blamed on the bed is a Z-offset problem wearing a disguise.