DFM for 3D Printing: A Practical Design Guide
Wall thickness, tolerances, supports, and hole sizing rules for printable parts.
Read the ArticleASA 3D Printing Material
Fused Deposition Modeling (FDM) · Engineering Plastics
UV- and weather-resistant plastic built for the outdoors.
What Is ASA?
ASA delivers ABS-like toughness with markedly better UV and weather resistance, making it the default choice for parts that live outdoors. It resists yellowing and embrittlement from sun exposure while holding good mechanical strength and heat tolerance.
Acrylonitrile Styrene Acrylate, printed with Fused Deposition Modeling (FDM). Every order is reviewed by our engineering team - no minimum order quantity.
When to choose ASA
Choose ASA whenever a part will be exposed to sunlight, rain, or outdoor weather. It is the only FDM material in our catalog engineered specifically for UV stability - ABS, PLA, and even nylon will yellow, crack, or degrade outdoors within months, while ASA holds its color and mechanical properties through years of sun exposure.
ASA's mechanical properties are comparable to ABS: similar tensile strength, impact resistance, and heat deflection (100 °C). The trade-off is cost - ASA runs at the $$$ tier vs $$ for ABS. If your part stays indoors, ABS saves money with equivalent performance.
For outdoor parts that also need high stiffness, there is no direct FDM composite in ASA - consider SLS PA12-GF or PA12-AF, which combine stiffness with reasonable weather tolerance in a powder-bed process. For outdoor parts that need flexibility, no FDM material excels; discuss your application with us.
Material Properties
Representative values - process- and orientation-dependent. Full technical datasheet available on request.
Process
Fused Deposition Modeling (FDM)
Tensile strength
37 ± 3 MPa
Elongation at break
8–12%
Flexural modulus
1,920 ± 130 MPa
Heat deflection (HDT)
100 °C @ 0.45 MPa
Density
1.07 g/cm³
Max build size
Up to 914 × 914 × 914 mm
Min wall thickness
1.2 mm
Resolution / layer
150 µm
Relative cost
$$$ (1 = lowest, 4 = highest)
Design Guidelines
Plan features to print reliably and assemble cleanly in ASA. Need DFM help?
Min wall
1.2 mm - 1.6 mm+ for load
Min hole Ø
1.5 mm - ream for precision
Clearance
0.4–0.6 mm - fit & moving parts
Max size
Up to 914 × 914 × 914 mm - 36 in per side
Dimensional tolerances
Typical tolerance is ±0.3 mm or ±0.5%, matching ABS. ASA has similar shrinkage characteristics to ABS, so warp mitigation practices apply: uniform wall thickness, avoid large flat unsupported spans, and orient critical features in the XY plane. Post-machining is available for critical bores and mating surfaces.
Printing notes
ASA prints at 240–260 °C nozzle / 90–110 °C bed and requires an enclosed, heated chamber - warping tendency is comparable to ABS. We hold chamber ambient at 45–55 °C. ASA is moisture-sensitive and must be dried at 65 °C for 4+ hours before printing; wet ASA produces visible bubbles and poor inter-layer adhesion. Support strategy mirrors ABS: breakaway supports with careful removal. Standard brass nozzles are fine. ASA emits mild fumes similar to ABS, so we run all ASA jobs with active chamber filtration.
How ASA Compares
ASA alongside related materials.
| ASA | ABS | ABS-GF | PC-FR | |
|---|---|---|---|---|
| Tensile strength | 37 ± 3 MPa | 33 ± 3 MPa | 36 ± 3 MPa | 60 ± 4 MPa |
| Heat deflection (HDT) | 100 °C @ 0.45 MPa | 87 °C @ 0.45 MPa | 99 °C @ 0.45 MPa | 113 °C @ 0.45 MPa |
| Flexural modulus | 1,920 ± 130 MPa | ≈ 2,200 MPa | 2,860 ± 130 MPa | 1,890 ± 70 MPa |
| Elongation | 8–12% | 10–15% | 3–5% | 5–8% |
| Density | 1.07 g/cm³ | 1.05 g/cm³ | 1.12 g/cm³ | 1.20 g/cm³ |
| Relative cost | $$$ | $$ | $$ | $$ |
When to Use ASA
Where ASA fits, where it doesn't, and what to use instead.
Outdoor enclosures and housings
Retains >80% impact strength after 2,000+ hours of accelerated UV weathering - conditions that destroy ABS in under 500 hours.
EnergyAutomotive exterior trim and mirror caps
100 °C HDT handles direct sun on dark-colored parts without warping, and UV stability prevents the chalking and cracking that rules out ABS for exterior use.
AutomotiveSignage and outdoor mounting brackets
Resists yellowing for 3+ years in direct sun exposure, maintaining brand-color consistency where painted ABS would need repainting annually.
Sensor and antenna housings
Weather resistance keeps enclosure seals intact and wall dimensions stable through temperature cycling from -20 °C to +80 °C ambient.
EnergySolar and environmental monitoring mounts
The only FDM material in our catalog engineered for multi-year outdoor deployment without UV-protective coatings or secondary finishing.
EnergyStrengths
- Only FDM material rated for multi-year UV exposure - retains color and strength where ABS, PLA, and nylon fail within months
- ABS-equivalent toughness (8–12% elongation, 37 MPa tensile) with 100 °C HDT - no mechanical trade-off for weather resistance
- Acetone vapor-smoothable like ABS, which also seals layer lines against moisture ingress in outdoor applications
Keep in mind
- Warps comparably to ABS on flat parts - requires enclosed heated chamber at 90–110 °C bed and uniform wall thickness within 2:1 ratio
- $$$ cost tier - roughly 30% more expensive than ABS; if the part stays indoors, ABS delivers equal performance for less
- No glass- or carbon-filled ASA variant available - for outdoor stiffness, move to SLS PA12-GF or PA12-AF with a UV-protective coating
Finishes & Colors
Finishing options and in-stock colors for ASA.
Standard
As-printed with support removal; visible layer lines.
Best for: Outdoor functional parts
Vapor Smooth
Improves sheen and surface sealing.
Best for: Cosmetic outdoor housings
In-Stock Colors
White
Black
Gray
Custom colors and dyeing available on request. Contact us for options.
ASA FAQ
Choose ASA whenever a part will see sustained sunlight or weather. It resists UV yellowing and embrittlement that degrade ABS outdoors, with similar strength and heat tolerance.
Like ABS it can warp, so keep walls uniform and avoid large unsupported flat spans. We print ASA in enclosed, temperature-controlled chambers to minimize warp.
Yes. ASA responds to acetone vapor smoothing similarly to ABS, producing a sealed, glossy surface. This also improves weather resistance by sealing layer lines.
ASA is not certified for food contact. Like ABS, it contains styrene compounds and FDM layer lines are difficult to sanitize. For food-contact applications, discuss alternatives with us.
ASA maintains color stability and mechanical integrity through several years of direct outdoor exposure, depending on climate. In independent testing, ASA retains over 80% of its impact strength after 2,000+ hours of accelerated UV weathering - conditions that destroy ABS in under 500 hours.
ASA has better UV stability. PA12 (SLS or MJF) is stronger and more isotropic but will yellow slightly under prolonged UV. For structural outdoor parts, PA12 is stronger; for cosmetic outdoor parts, ASA holds its appearance longer.
We hold ±0.3 mm or ±0.5% on ASA parts, matching ABS. Warp risk on large flat parts is similar to ABS. We recommend uniform wall thickness and print in enclosed heated chambers.
ASA at $$$ is pricier than ABS but justified for any outdoor application. For indoor-use production parts, ABS saves about 30%. For outdoor production volumes above 50 units, SLS or MJF nylon may offer better per-part economics.
Technical Documents
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