ABS and ASA share the same core requirements: an enclosure, a hot bed, and ventilation. They differ in one thing that matters. This guide covers when to use each, the print settings for both, how to deal with warping, and the one trick only ABS can do.
ABS (acrylonitrile butadiene styrene) was the original hobbyist engineering filament before PLA became viable. Strong, heat-resistant to around 100°C, sandable, and uniquely compatible with acetone smoothing for a near-perfect surface finish. Its drawbacks are well-documented: aggressive warping, fume production, and sensitivity to ambient temperature changes during printing.
ASA (acrylonitrile styrene acrylate) was developed to address ABS’s main limitation. It handles UV exposure where ABS would yellow and become brittle within months. ASA is slightly better to print than ABS in most setups, holds the same high-heat resistance, and requires the same enclosure and bed temperature. For outdoor applications, it’s the clear choice between the two.
Both materials live on this page because the honest answer to most questions about ABS leads directly to whether ASA is the better call.
This doesn’t need to be complicated.
Use ABS when: you need acetone vapour smoothing. ABS dissolves in acetone; ASA does not. For a near-injection-moulded surface finish without sanding, ABS is the only common FDM filament that gives you this. It’s the one thing ABS still does that nothing else can match.
Use ASA when: the part will see sunlight or outdoor exposure. ASA maintains its colour and mechanical properties under UV where ABS degrades noticeably within months. If you’re choosing between the two and have no specific reason to need acetone smoothing, ASA is the better default.
Consider PETG first: most applications that seem like ABS or ASA jobs are PETG jobs on closer inspection. PETG handles up to around 80°C, requires no enclosure, and produces no fumes worth worrying about. If the part doesn’t need to survive above 80°C and won’t see outdoor UV exposure, PETG is simpler and more reliable to print.
Full material comparison: PLA vs PETG vs ABS vs ASA.
These requirements apply to both materials.
Enclosure: both need one. ABS warps aggressively in any draft or temperature fluctuation. ASA is slightly more forgiving but still fails on larger prints without a stable chamber temperature. Aim for 40-50°C ambient inside the enclosure. Let the printer warm up with the bed at temperature for 10-15 minutes before starting the print.
Bed temperature: 100-110°C for ABS, 90-110°C for ASA. Most modern printers with heated beds handle this range. A PEI sheet at these temperatures works reliably for both materials without adhesive.
Adhesion: the first layer is critical. Both ABS and ASA need a well-adhered first layer to prevent corner lifting. Use a brim of at least 5-10mm on anything with a footprint larger than a few centimetres. Some setups add a thin layer of PVA glue on the PEI sheet for extra grip with ABS specifically.
Fumes: ABS produces styrene fumes. This is not optional to address. Print in an enclosure with a HEPA and activated carbon filter, or in a space with airflow to the outside. ASA produces fewer fumes than ABS but still warrants ventilation. Both materials are manageable with proper setup.
Nozzle: 230-250°C. Start at 240°C. ABS has a wide temperature window and most brands are forgiving across this range.
Bed: 100-110°C. First layer speed: 20-30mm/s. The first layer determines whether the print survives.
Speed: 40-60mm/s for the main body. Slow the perimeters slightly.
Layer height: 0.12-0.28mm depending on detail requirements.
Cooling: off. Running the cooling fan on ABS causes layer delamination and cracking. Keep it off for the entire print. At most 10-15% on the very top layers of fine features.
Brim: use it. 5-10mm minimum on anything larger than small parts.
Acetone smoothing is ABS’s defining feature. The process: place the finished print on a raised platform inside a sealed container. Pour a small amount of acetone into the bottom of the container, not touching the part. Seal it for 15-30 minutes. The vapour dissolves the surface layer uniformly, filling in layer lines and leaving a smooth finish. Check at 15 minutes. The longer it runs, the more material dissolves and the softer fine details become. On a well-printed ABS part, the result is genuinely close to injection-moulded.
Nozzle: 240-260°C. Slightly hotter than ABS. Start at 250°C.
Bed: 90-110°C. ASA adheres well to PEI at 100°C without adhesive in most cases.
Speed: 40-60mm/s. First layer at 20-30mm/s.
Layer height: 0.12-0.28mm.
Cooling: off or minimal. Same reasoning as ABS. Rapid cooling of ASA layers causes delamination.
Brim: use it.
UV resistance in practice: ASA is not infinitely UV-stable, but it handles the UV exposure that would destroy ABS within months. In direct Florida sunlight, ASA print colour holds for years where ABS would yellow and lose mechanical properties noticeably. For outdoor signage, exterior fixtures, and display pieces that see regular direct sun, ASA is the correct material. For items in shade or only occasional outdoor exposure, PETG is often sufficient and easier to print.
Warping is the defining failure mode for both materials. A corner lifts, the part detaches, hours are lost. Here’s what actually reduces it.
Let the enclosure temperature stabilise first. Starting a print immediately after the bed reaches temperature means the first layers go down in a cold chamber. Wait 10-15 minutes after bed temperature is reached before starting.
Use a brim. A 5-10mm brim dramatically increases first-layer adhesion area and counters the stress that pulls corners up. Non-negotiable on parts with a large footprint.
Keep the fan off. Any forced airflow on a cooling ABS or ASA layer makes the warping problem worse, not better.
Don’t open the enclosure door during a print. Even briefly introducing cooler ambient air at a critical layer can cause the current layer to contract and lift.
Add fillets to sharp corners where possible. Right-angle corners concentrate the stress that causes warping. Radius them in the design and the print holds better.
Rotate the part if one spot keeps failing. Airflow patterns inside an enclosure are not always even. A 45-degree rotation on the build plate sometimes eliminates a persistent problem.
If all of the above is in place and warping still happens: raise the bed temperature by 5°C and try again.
| Material | Nozzle | Bed | Enclosure | Cooling | Key Advantage |
| ABS | 230-250°C | 100-110°C | Required | Off | Acetone smoothing; high heat indoors |
| ASA | 240-260°C | 90-110°C | Recommended | Off or minimal | UV resistance; outdoor use |
Most OreKo models are designed for PLA. ABS and ASA become the right call in specific situations.
Deck boxes in extreme heat environments: PETG handles up to around 80°C. A closed car in South Florida on a summer day can reach 85-90°C at dashboard level. For deck boxes stored in the car, ASA is the correct material. Same model file, same slicer settings structure, just different filament in the printer.
Display pieces where surface finish matters most: ABS with acetone smoothing produces a surface PLA, PETG, and ASA cannot match without significant post-processing work. A display chess piece, trophy, or collector’s item where the surface is the whole point is a reasonable case for ABS.
Outdoor display fixtures and props: scale models or prop pieces that live outside or in direct sun need UV-stable material. ASA holds colour and shape where PLA degrades in weeks and PETG follows within months under direct sunlight.
For anything living indoors in air conditioning: PLA or PETG will outlast any practical need for the part.
We use eSUN ABS+ and eSUN ASA for the applications above. ABS+ is eSUN’s improved ABS formulation that warps less than standard ABS and still smooths cleanly with acetone. Both run consistently at the settings documented here.
eSUN ABS+ and ASA are available through the eSUN Official Store.
Disclosure: the eSUN link above is an affiliate link. If you purchase through it, we earn a small commission at no cost to you. We only recommend products we use ourselves.
Every OreKo model is verified in PLA. For high-heat or outdoor applications, the same file works in ASA with the settings above.