Material Comparison

ABS vs ASA

Both need an enclosure. One handles UV, the other doesn't. Here's when to pick which.

Last updated: March 2026

Quick comparison

ABS

ASA

Nozzle Temp

230 - 250 °C

240 - 260 °C

Bed Temp

100 - 110 °C

Strength

Strong, moderate flex

Heat Resistance

~100 °C (Tg)

UV / Outdoor

Poor - yellows and degrades

Excellent - UV stable

Ease of Printing

Moderate - needs enclosure

Warping

High

Moderate (less than ABS)

Fumes

Strong - ventilation required

Acetone Smoothing

Yes - vapor smoothing works well

Slower vapor smoothing (more resistant than ABS)

Typical Price

$15 - 25/kg

$18 - 30/kg

Best For

Indoor functional parts, enclosures

Outdoor parts, automotive, UV exposure

When to use

ABS

ABS is the classic engineering filament. It prints well in an enclosed chamber, handles heat up to ~100 °C[1], and offers good impact resistance with moderate flexibility. Its biggest advantage over ASA is acetone vapor smoothing - you can achieve a glossy, injection-molded finish that no other filament matches. ABS is also more affordable and more widely available than ASA.

Ideal for: indoor functional parts, prototypes, electronics enclosures, and any project where you want a smooth post-processed finish via acetone vapor smoothing.

Community tip: ABS warps aggressively without an enclosure. Even a simple cardboard box over your printer can make a noticeable difference. A heated chamber at 50-60 °C virtually eliminates warping.

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When to use

ASA

ASA is ABS that can survive outdoors. It shares nearly identical mechanical properties - similar strength, heat resistance, and layer adhesion - but adds excellent UV stability. Where ABS yellows, becomes brittle, and cracks after months in sunlight, ASA holds its color and structural integrity for years.[2] It also warps slightly less than ABS, making it marginally easier to print.

Ideal for: anything going outdoors - garden fixtures, car mounts, drone parts, outdoor signage, weatherproof enclosures, and any UV-exposed functional part.

Community tip: ASA still needs an enclosure and good ventilation, just like ABS. The fumes are comparable. The only real difference is what happens after the print leaves the printer - ASA survives the elements, ABS does not.

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The community verdict

If it's going outside, use ASA. If it's staying inside, ABS is more affordable and can be vapor-smoothed. Both need an enclosure and good ventilation. That is the consensus across Reddit, Discord, and YouTube. The materials are so mechanically similar that the decision almost always comes down to one question: will this part see sunlight?

If you are already set up for ABS (enclosed printer, ventilation sorted), switching to ASA requires no hardware changes - just a slightly higher nozzle temperature and a different spool. Many users keep both on hand and pick based on the project.

Frequently Asked Questions

Can I use ABS outdoors?

No, ABS degrades in UV light.[1] It yellows, becomes brittle, and loses strength within months of sun exposure. Use ASA instead.

Does ASA need an enclosure?

Yes, just like ABS. ASA warps without an enclosed build chamber. Both materials emit fumes that should be ventilated.

Is ASA stronger than ABS?

Very similar. ASA has slightly better impact resistance and significantly better UV stability, but the raw strength numbers are comparable.

Can I smooth ASA with acetone?

Yes, ASA can be acetone vapor-smoothed, but it is more resistant to acetone than ABS — the process takes longer and the results are more subtle. ABS remains the better choice if a glossy, injection-molded surface finish is your primary goal.

References

Prusa Knowledge Base — ABS. https://help.prusa3d.com/article/abs_2058
Prusa Knowledge Base — ASA. https://help.prusa3d.com/article/asa_1809