ASA problems: warping, cracking, fumes, plate damage

This guide is for ASA prints that lift at the corners, split between layers, won't stick or won't let go of the plate, smell strongly, or come out bubbly. It collects what Bambu Lab, Prusa, Polymaker, Overture, eSUN, SUNLU, Anycubic and ERYONE say about their own ASA, and keeps each setting to the product or printer the maker names. For the general causes of warping and weak layers in any material, see our warping guide and layer adhesion guide. ASA shares much of this with ABS, which our ABS printing problems guide covers. Start here:

Does ASA need an enclosure?

Seven of the eight makers here require or recommend an enclosure for their ASA, though SUNLU says so only in Chinese, on its data sheet. Anycubic doesn't say either way on the pages we checked:

The chamber temperatures the makers give:

Polymaker's ASA wiki says to "Heat up your build plate to 90-100˚C for 10 minutes before starting your print so that the chamber has time to heat up." On Bambu's enclosed printers, the filament guide's plate table says "NO" to removing the upper glass cover for ASA.

Open-frame printers

Bambu's A1 FAQ says that because of its open frame and lower chamber temperature, the A1 "is prone to reduced interlayer strength when using high-temperature filaments." It doesn't recommend ASA on the A1 for large models, or models with high infill, that need strong layers, but says these materials "can be used on A1 for printing small-sized models with low infill densities."

Without an enclosure, Prusa's ASA guide offers "one simple alternative": the draft shield in PrusaSlicer, which "will create a wall around the object and keep the model slightly warmer, mitigating the warping." See the draft shield notes under Warping below. Our enclosure planning guide covers what an enclosure does and doesn't do.

Part size limits

Several makers say ASA sets a limit on part size, not only on settings:

• Polymaker ASA wiki: "In general a non-enclosed 3D printer with 90˚C bed temperature and 260˚C printing temperature can handle models smaller than fist size." Bigger prints need an enclosed printer at about 40–50 °C, and models bigger than about 15–20 cm in any direction need an actively heated chamber of about 70 °C or more.
• Bambu Lab ASA: "ASA is prone to warping when printing large size and/or high infill density model." Its first tip is "Not recommended to print too large size and/or high infill density models."
• Bambu Lab warping guide: "Large flat models printed in ABS, ASA, or PC will almost always warp without an enclosure." Without one, it says to switch to PLA, PLA-CF, PETG or PETG-CF for large prints.
• Prusament ASA: lists "Large models have a tendency to warp" as a con, and says "Even with the heatbed set to 110°C, the prints can shrink and warp, causing them to detach from the print bed." It says this "can be eliminated by printing inside an enclosure or by adding a tall skirt around the object."

If the part doesn't need ASA's outdoor or heat performance, our ASA vs PETG guide compares the easier option, and our PETG printing problems guide covers PETG's own quirks.

Warping

Bambu's ASA store page gives three fixes: don't print too large or too dense, "use enclosure printers and ensure the build plate is properly glued before printing," and "set lower printing speed and higher heatbed temperature." The other makers add:

• Bambu Lab warping guide: for corners lifting on ABS or ASA, raise the bed temperature by 10–15 °C and "Close all doors and top cover." For large flat models, it suggests Gyroid infill at 25% or less. For sharp corners that pop up, it suggests painted brim ears on just those corners.
• Polymaker warping guide: "for ABS and ASA you can help to reduce your warping issues by extruding slower and at a higher temperature."
• Polymaker ASA: "Use an enclosure, avoid drafts, and keep the cooling fan off."
• Prusa: "For high-temperature materials such as PC-Blend, ASA, or ABS, try using a printed skirt (draft shield)," print more objects at once, and orient the problematic parts "towards the center of the heatbed."
• ERYONE: "During printing, try to avoid strong wind and temperature fluctuations to reduce the risk of warping and deformation."
• SUNLU: "Use a 90–110°C heated bed with a glue stick or PEI sheet to eliminate warping." The same page also gives 80–120 °C, and its spec block and data sheet give 80–100 °C, so check which figure your printer can hold.
• Prusa, on drafts: when ventilating the room, "do not create a draft around the print – this will negatively impact the result."

Draft shields, skirts and brims

PrusaSlicer's draft shield "creates a skirt as tall as the tallest object in the scene," and Prusa says it "can be used to protect ABS, ASA, and other materials from warping by creating a micro-climate around the printed part and protecting the print from draft/wind." The Prusament ASA data sheet adds that "A 3 mm brim (or taller) can improve the adhesion of edges and corners of larger objects to the print sheet."

Our warping guide covers plate cleaning, first-layer checks and drafts for any material.

Layer splits and cracking

Bambu says interlayer cracking along the Z direction "is common during printing with materials such as ABS, ASA, PC, PET-CF, and PA-CF." Its fixes, in order:

1. Clear a partial clog. "A slight nozzle clog may prevent filament extrusion during a specific layer, manifesting similarly to cracking."
2. Raise the nozzle temperature or slow down, which "allows the extruded filament more time to bond with the layer below."
3. Reduce the part cooling fan, lowering "Max fan speed" if the walls are being cooled at 60%.
4. Raise the bed by 5–10 °C, and the chamber by 5 °C if the printer has active chamber heating.

Polymaker's ASA wiki says "The hotter and slower you print, the better your layer adhesion will be," but warns that you may get "uglier overhangs": "You will battle between great layer adhesion and great overhang quality." It also says to "Keep your cooling fan off if you are having layer adhesion or build plate adhesion issues." Its product page says to use 240–260 °C "For faster printing or improved layer adhesion."

Should the part fan be on or off?

Start from the fan setting your filament's maker gives. If layers split, Bambu says to reduce the fan and Polymaker says to keep it off.

Our layer adhesion guide covers the other checks.

Bed, plate and glue

Bambu adds rules for its own plates:

• Textured PEI Plate: "When printing PC/PA/ABS/ASA filaments on a Textured PEI Plate, it may be necessary to apply a layer of glue stick."
• Gluing: "Ensure that the print adheres properly to the plate without causing damage to the surface by sticking too tightly. Otherwise, the sheet may bubble or crack." It says "third-party glues are strongly discouraged and may damage the plate."
• Cool Plate SuperTack: Bambu ASA is "Not compatible with Cool Plate SuperTack."

On Prusa printers, Prusa says "ASA sticks very well to our print sheets (smooth and powder coated) but other print surfaces, like glass, might require a layer of acetone with dissolved ASA (or ABS)." It also says: "Do not put acetone or ABS/ASA juice on the powder-coated sheet!" Polymaker suggests Magigoo Original if you're having bed adhesion issues. Our first-layer adhesion guide covers the general checks.

Sticking too hard and plate damage

ASA can grip some plates hard enough to damage them. The Prusament ASA page says:

"For ASA printing, we recommend using the satin spring steel sheet. With the powder-coated or smooth sheet, the adhesion of the material can be too strong, which could potentially result in damage to the surface of the sheet."

For the textured and smooth PEI sheets, it says to clean the surface with isopropyl alcohol and apply glue, and "To remove the print, wait until it cools down – it will then pop off easily."

The other makers point the same way. Polymaker says to "Apply a suitable adhesive as a release layer, and let the build plate cool before removing the print." Bambu's filament guide says to "wait a few minutes until the plate and model have fully cooled before removing the print," and its plate guide says prints come off its Textured PEI Plate easily at room temperature, recommending "waiting until it reaches 35℃ or lower."

For freeing a stuck part, see our print stuck to the bed guide. For a sheet that's already marked or torn, see our PEI sheet damage guide.

Fumes and ventilation

These are the makers' own statements about their ASA. We don't add to them.

• Prusa: lists "Potentially dangerous fumes (styrene)" as a con, and says "It's important to run the prints in a well-ventilated room because the material releases fumes and substances that could pose a potential health risk." Prusament ASA lists "Contains styrene" and "Produces odors during printing (less than ABS)."
• Bambu Lab ASA: "Pungent and unpleasant odors may be released during printing. Make sure your printer is placed in a well-ventilated area." Its safety tips say to print "in a well-ventilated area, or install an effective air filtration or exhaust system," that "this filament may release harmful gases, including styrene, which can cause dizziness or nausea," to wear "a protective mask with a vapor filter (such as an activated carbon mask)" for extended operation, and to increase ventilation or pause printing if people with asthma or respiratory conditions, pregnant women, or children are present.
• Bambu Lab A1: "ABS and ASA release harmful and irritating gases during printing," and Bambu recommends "not to use A1 for printing ABS and ASA unless in well-ventilated environments at a safe distance from people."
• Polymaker: "Print in a well-ventilated area." Its ASA wiki says "normally the smell during ASA printing is stronger than PLA/PETG," and "it is recommended to have proper ventilation and filtration regardless of the plastic you are printing with."
• OVERTURE: "While Overture ASA does produce some odor during printing, the emissions are generally less harmful compared to those from ABS." It advises "ensuring good ventilation and considering air filtration."
• SUNLU (data sheet): "The print processing area should be well ventilated," and "Local extract ventilation should be used when necessary."
• Anycubic: says its ASA "produces minimal odor" compared with traditional ABS. That's its claim for its own product.

Bambu's own documents differ on odor: the ASA data sheet lists odor as "Odorless," while the store page warns of pungent odors and styrene. The store page's safety tips are the more cautious of the two. Our ABS vs ASA guide and enclosure planning guide cover ventilation and filtration in more detail.

Drying

Bambu's data sheet says to print and store its ASA below 20% RH, sealed with desiccant, and its drying guide says "Do not use a microwave oven or a kitchen oven to dry filaments." Our wet filament guide covers how to tell if a spool is damp.

Bambu printers: AMS lite, plates, cover

• AMS lite. Bambu's ASA store page says "AMS 2 Pro, AMS HT & AMS Compatible" and "AMS lite NOT Compatible." Its filament guide lists ASA as "Compatible" in a combined AMS / AMS lite column. The store page is specific to Bambu ASA, so follow it for that spool.
• Plates. No Cool Plate ("Not recommended") and no Cool Plate SuperTack ("Not compatible") for Bambu ASA.
• Top cover. Keep it on: the filament guide says "NO" to removing the upper glass cover for ASA, and the warping guide says to "Close all doors and top cover."
• Maintenance. Bambu's ASA-CF and PAHT-CF usage guide says volatile substances from ABS, ASA "or similar filaments" can build up inside the printer, and recommends a cleaning "after every 5 spools (5 kg) of ABS or ASA filament." For its X, P and H2 series, it says the activated carbon filters should be replaced every 1,440 printing hours, about 60 days.

UV and outdoor parts

Every maker here sells its ASA for outdoor use. Only some publish anything behind the claim:

• Polymaker says that after a two-year natural aging test, its ASA showed a color change value (ΔE) below 2.5, and in an accelerated test a ΔE below 5 "and minimal tensile strength loss, even after exposure to 8000 kj/m2 irradiation." It says outdoor parts "maintain integrity for a minimum of two years."
• Prusa lists "High UV resistance" and says Prusament ASA "will keep toughness and durability for a long time and will not turn yellow."
• SUNLU's product page says its ASA remains "fade-resistant and shape-stable even after prolonged exposure to outdoor conditions." Its data sheet adds: "The product may yellow under the action of ultraviolet light, so it should be stored away from direct sunlight."
• Bambu Lab describes "Extraordinary UV Resistance" and asks you to store the filament "away from direct sunlight." Anycubic, eSUN, ERYONE and OVERTURE also state UV or weather resistance, without a test figure on the pages we checked.

For choosing between ASA and its alternatives for outdoor parts, see our ABS vs ASA guide and ASA vs PETG guide.

What are the side effects of a hot enclosure?

• Printer parts. Prusa says "printing a lot of ASA in an unventilated enclosure can cause the fan shroud and/or extruder plastic parts to deform over time. This may impact performance or cause issues."
• Electronics. Polymaker's warping guide says that when ambient air gets this hot, "Stepper motors and other electronics can overheat and cause your printer to malfunction," and suggests keeping the power supply and board outside the chamber if possible.

A sensible order

1. Confirm your printer and filament maker support ASA on your setup, and that the part is within the size they suggest.
2. Dry the spool to its maker's setting.
3. Clean the plate and apply glue or a release layer where your plate or filament maker says to. On Prusa sheets, use the satin sheet or glue.
4. Close the enclosure and let the chamber warm up before printing.
5. Set the bed, nozzle and fan from the filament maker's numbers.
6. Add a brim, and a draft shield if your printer is open.
7. If corners still lift, slow down and raise the bed within range.
8. If layers split, reduce the fan, raise the nozzle temperature within range and slow the walls.
9. Let the plate cool before removing the part.
10. Print in a well-ventilated area, as Prusa, Bambu, Polymaker, OVERTURE and SUNLU say.

Checklist

• Enclosed printer, or a small, low-infill part if your printer is open.
• Chamber warm: 45–60 °C in Bambu's data sheet, at least 50 °C in Polymaker's warping guide.
• Glue or another release layer on the plate. On Bambu printers, no Cool Plate or Cool Plate SuperTack.
• Bed inside the filament maker's range.
• Fan off or low, as your filament maker says.
• Brim on, and a draft shield where there's no enclosure.
• No drafts across the printer.
• Filament dried to its maker's setting and stored sealed with desiccant.
• Plate cooled before the part comes off.
• Bambu ASA kept out of the AMS lite.
• A well-ventilated room. On a Bambu A1, ASA only in a well-ventilated space at a safe distance from people.

If you're still choosing a spool, our ASA shortlist compares the spools themselves.

How this guide was checked

This is a research-based guide. We haven't run these tests for it. Every setting, quote and recommendation comes from the Bambu Lab, Prusa Research, Prusa Polymers, Polymaker, OVERTURE, eSUN, SUNLU, Anycubic and ERYONE pages and data sheets listed in the sources, retrieved on 2026-10-13. Settings and claims are kept to the product or printer each page names, and where makers disagree we show both. Safety statements are the makers' own. Read more in our editorial standards.

Specialty materials: what to check before you buy a spool ↗