Bed Surfaces & Adhesion
PEI, glass, textured plates, brims and rafts — how to get prints to stick (and release).
Know Your Build Surface
The build plate is half of the adhesion equation. The common surfaces each behave differently:
- Textured PEI (powder-coated): forgiving, great for PLA/PETG, leaves a pleasant matte finish. The most popular all-rounder.
- Smooth PEI: strong grip and a glossy bottom, but PETG can stick too well — use a glue release.
- Glass: dead-flat, glossy bottoms, needs glue or hairspray for grip; prints pop off as it cools.
- Spring steel (flexible): any coating on a removable magnetic plate — flex it to release prints instead of prying.
The Golden Rule: Keep It Clean
Skin oils are the #1 cause of adhesion failure. Wash the plate with dish soap and warm water periodically, and wipe with isopropyl alcohol (90%+) before important prints. Avoid touching the print area with bare fingers.
If adhesion has slowly gotten worse over weeks, the plate is almost certainly just dirty — clean it before changing any settings.
When You Need Help: Brims, Rafts and Glue
For tall, small-footprint, or warp-prone prints, add bed contact:
- Brim: a flat skirt attached to the part's edge — adds hold for tippy models, peels off easily. The first thing to try.
- Raft: a full platform under the part — maximum adhesion and bridges an uneven bed, but uses material and can mar the bottom.
- Glue stick / PVA: a thin layer adds grip on glass and acts as a release layer that protects smooth PEI from PETG.
Most prints need none of these once leveling and Z-offset are correct.
Releasing Prints Safely
Let the bed cool before removing — most surfaces release on their own as they contract. With a flexible plate, remove it and gently flex; never gouge a fixed surface with a metal scraper, which scratches the coating and ruins future adhesion. If a part is truly stuck, a few minutes in the freezer makes it pop free.