Every 3D printing forum has the same recurring thread: “why won’t my print stick to the bed?” The honest answer is that adhesion failures follow a predictable order, and most people skip straight to the least likely fix — buying glue — before checking the two things that cause the vast majority of failed first layers. This guide walks the fixes in the order that actually solves the problem fastest.
Bed adhesion fixes by the numbers
- 90% — the isopropyl alcohol concentration Prusa’s knowledge base recommends for cleaning a print surface before every print. Lower-percentage IPA, and any IPA marketed for skin or nails, commonly contains moisturizing additives that leave a film behind rather than removing one.
- 40°C vs 55°C vs 35°C — Bambu Lab’s own PLA bed temperature by plate type: Cool Plate, smooth PEI, and textured PEI respectively. The same filament needs a different setting depending entirely on which plate is installed — a leading cause of “it worked yesterday” adhesion complaints after a plate swap.
- 70-85°C — PETG bed temperature range on textured PEI per Bambu’s guidance, against just 55-60°C on a Cool Plate SuperTack. Running PETG at Cool-Plate temperatures on a textured PEI plate is a common under-temperature mistake.
- 80-100°C — the PEI-side bed temperature range Bambu recommends for ABS, which is why ABS, ASA, and PC are routed to an Engineering or High-Temp plate rather than a standard one.
- A couple hundred hours — roughly how long a PEI sheet holds its adhesive properties under normal use before the surface glazes over and grip drops off, per Prusa’s documentation. An acetone wipe restores it; most people replace the sheet before trying that first.
Adhesion aids compared
| Fix | Cost | Fixes | Best for |
|---|---|---|---|
| 90% IPA cleaning | $6-10/bottle | Oil/fingerprint contamination | Every print, every material |
| Re-leveling / Z-offset | Free | Squish too high or too low | First layer gaps or scraping |
| Bed temperature correction | Free | Wrong temp for plate/filament | Corners lifting mid-print |
| 3D printing glue stick | $6-12 | Weak natural grip (ABS, ASA, PC, nylon) | Engineering-plate materials |
| Brim (slicer setting) | Free | Small footprint, tall/warping parts | Tall, narrow, or fine-detail prints |
| Acetone wipe / sheet replacement | $3-25 | Glazed, worn-out PEI surface | Sheets past a few hundred hours |
1. Clean the plate — the fix that solves most adhesion problems
90% Isopropyl Alcohol (IPA), print-bed grade
- Prusa's official guidance: clean with roughly 90% IPA before every print, always on a cold plate.
- Avoid dermal/cosmetic IPA (hand sanitizer, nail products) — moisturizing additives leave a residue that actively works against adhesion.
- If adhesion still degrades over time, dish soap and warm (not hot) water removes oils and sugars that IPA alone does not touch.
- A single unwiped fingerprint on a PEI sheet is enough to cause a localized release on an otherwise good print.
- Re-apply after handling the plate with bare hands — gloves are cheap insurance if you touch it often.
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Adhesion problems get diagnosed backwards more often than any other issue in FDM printing — people assume a hardware fault and start re-leveling, re-flashing firmware, or buying a new plate before ever wiping the surface down properly. Skin oil transfers to a plate the moment you touch it, and PEI’s grip depends on surface chemistry, not just texture. Wipe with 90% IPA, let it flash off completely (seconds, not minutes), and re-test before changing anything else.
2. Fix the first-layer squish
If cleaning didn’t solve it, the next most common cause is a first layer that is either too high (not squished flat enough to bond) or too low (scraped so thin it doesn’t extrude evenly). This is a leveling and Z-offset problem, not a temperature or chemistry problem, and it looks identical to an adhesion failure from the outside — filament balls up, drags, or simply doesn’t stick to specific spots on the bed.
Run your printer’s bed-leveling routine, then dial in Z-offset by eye: the first line should lay down with visible pressure — flattened, not round in cross-section — but not so thin that you can see the plate texture through gaps. If one corner sticks and the opposite corner doesn’t, that’s a leveling problem masquerading as an adhesion problem, and no amount of glue fixes it.
3. Match bed temperature to plate type, not just filament
| Filament | Cool Plate | Smooth PEI | Textured PEI | Engineering/High-Temp |
|---|---|---|---|---|
| PLA | 40°C | 55°C | 35°C | — |
| PETG | 55-60°C | 60-70°C | 70-85°C | — |
| ABS / ASA | — | — | — | 80-100°C (+ glue) |
| PC / Nylon | — | — | — | 90-110°C (+ glue) |
This is the fix people skip because it feels like it “should” already be right — most slicer profiles set a generic bed temperature that assumes one plate type. Bambu Lab’s own documentation shows PLA wanting 55°C on smooth PEI but only 35°C on textured PEI, and PETG jumping from 55-60°C on a Cool Plate to 70-85°C on textured PEI. If you swapped plates and didn’t update the temperature in your slicer, that mismatch alone explains corners lifting mid-print or a first layer that never quite locks down.
4. Glue stick or adhesion spray — for the materials that actually need it
3D Printing Glue Stick
- Engineering and High-Temp plates are designed to pair with glue for ABS, ASA, PC, and nylon.
- These filaments run hot (80-110°C bed) and shrink more while cooling, so they need mechanical grip beyond plate chemistry alone.
- A thin, even layer is enough — heavy application makes removal messier, not more secure.
- Use a purpose-made 3D printing stick, not a household glue stick — the formulations differ.
- Not a fix for PLA or PETG adhesion problems; if a "safe" filament needs glue to stick, look at cleaning and temperature first.
Glue and adhesion sprays get reached for first because they’re the most visible, most-advertised fix — and they genuinely are the correct tool for high-temperature engineering filaments. But applying glue to solve a PLA or PETG adhesion problem is usually treating a symptom: a properly cleaned, leveled, and temperature-matched plate holds PLA and PETG with no glue at all. If you need it there, something upstream is still wrong.
5. Use a brim for small, tall, or warp-prone parts
A brim is the cheapest structural fix available and it’s built into every mainstream slicer. It prints a single-layer flat ring of extra plastic attached to your part’s base, increasing the surface area gripping the bed without adding the height, material, or removal hassle of a full raft. Tall, narrow parts (masts, figures, anything with a small footprint relative to its height) and materials prone to warping (ABS, ASA) both benefit. A 5-8mm brim is a reasonable default; increase it for taller or more warp-prone prints.
6. Know when your PEI sheet is actually worn out
Replacement PEI Build Plate
- Prusa's documentation states PEI can lose adhesive properties after roughly a couple hundred hours of use.
- Try an acetone wipe first — it strips the glazed layer that builds up and often restores grip without a replacement.
- Replace only after acetone-cleaning fails to bring adhesion back to normal.
- Match the plate to your exact bed size and mounting style (magnetic, clip, or direct) before ordering.
- A worn plate shows a visible sheen or gloss where prints used to release cleanly by hand.
The diagnostic order, in one paragraph
Clean with 90% IPA on a cold plate first — this alone fixes more adhesion complaints than every other fix combined. If that doesn’t do it, re-level and check your Z-offset; a first layer that isn’t squished flat looks exactly like a sticking problem from the outside. Next, confirm bed temperature matches both your filament and your specific plate type, since the same filament wants different temperatures on different surfaces. Only after those three are ruled out should you reach for glue (for ABS/ASA/PC/nylon specifically) or a brim (for small or warp-prone geometry). If a worn PEI sheet is the culprit, try an acetone wipe before buying a replacement.
Related guides
- Best 3D printer filament — PLA, PETG, ABS, and TPU compared, including which ones need glue.
- Best 3D printer accessories — the full accessory list, including cleaning and adhesion supplies.
- Best 3D printer nozzle — a different first-layer failure mode people often confuse with adhesion.
- Best 3D printers of 2026 — our head-to-head pillar ranking.
- Is Amazon Prime worth it for 3D printing shoppers? — the break-even math on fast-shipping consumables like these.