Acrylonitrile Styrene Acrylate (ASA) filament is growing in popularity among 3D printing enthusiasts and professionals. But how does it actually compare to common filaments like ABS and PETG?
In this comprehensive guide, we’ll break down the key properties, benefits, and drawbacks of ASA filament. We’ll also compare it directly against ABS, PETG, PLA, and other materials on factors like temperature resistance, UV resistance, strength, flexibility, ease of printing, and more.
By the end, you’ll understand exactly why ASA is becoming a top choice for outdoor use cases and other demanding applications. Let’s dive in!
What is ASA Filament?
ASA filament is a thermoplastic that combines properties from ABS and acrylic polymers. The result is a material that has high temperature resistance like ABS but better UV stability thanks to its acrylic component.
Some key properties of ASA include:
- High impact strength and toughness
- Good tensile strength
- High heat deflection temperature (around 105°C)
- UV and weather resistance
- Low moisture absorption
- Easy post-processing like sanding and painting
The excellent blend of mechanical properties, heat resistance, and UV resistance make ASA an ideal choice for applications like outdoor enclosures and automobile parts. Products printed with ASA can withstand long-term sunlight exposure as well as hot environments.
ASA vs. ABS Filament
ABS has long been the go-to filament for professional 3D printing applications. So how does ASA compare?
Temperature Resistance
Both ABS and ASA have a high heat deflection temperature around 100°C. This gives products printed with either material good thermal stability in hot environments like inside automobiles.
However, ASA is generally considered to have slightly better temperature resistance than ABS. Its acrylic component boosts stability at high temperatures.
Weathering Resistance
One of the biggest advantages of ASA over ABS is UV and weather resistance. ABS will show noticeable color fading, cracking, and degradation when exposed to sunlight over time. ASA has much better stability thanks to its acrylic backbone.
Finished ASA parts can withstand extended outdoor use with minimal material degradation. This makes it ideal for applications like outdoor enclosures, tool housings, robotics parts, and more.
Strength
ABS and ASA have similar levels of tensile and flexural strength. Both can produce rigid, durable parts able to withstand mechanical stresses.
Impact resistance is also comparable, although ASA may have a slight edge. The acrylic portion improves impact toughness vs. pure ABS.
Ease of Printing
Printing ASA filament is very similar to ABS in terms of optimal settings and required equipment:
- Heated bed around 100°C
- Nozzle temperature 240-260°C
- Enclosed chamber recommended to prevent warping
The one difference is that ASA generally requires slightly higher extruder temperatures than ABS. Still, those accustomed to printing ABS will find the transition to ASA fairly seamless.
Post-Processing
A major advantage of both ASA and ABS is that they can be easily machined, sanded, painted, and modified after printing. This allows creating professional surface finishes or assembling multi-part designs.
ASA vs. PETG Filament
After ABS, PETG is likely the next most common filament for functional prototyping and end-use parts. Here’s how it stacks up against ASA.
Temperature Resistance
PETG has good temperature stability up to around 70-80°C before softening. However, ASA has a much higher deflection temp around 105°C, making it suitable for hot environments where PETG would warp or deform.
UV / Weathering Resistance
PETG is naturally transparent, so it already blocks UV compared to other opaque filaments. However, ASA has even better UV resistance thanks to its acrylic component. ASA is less prone to discoloration, hazing, and cracking over time versus PETG.
Mechanical Strength
In terms of tensile strength, PETG and ASA are fairly similar. Both produce rigid, durable parts.
However, ASA has noticeably higher flexural strength and impact resistance. The tough acrylic backbone makes ASA parts more resilient to sudden impacts and other mechanical stresses.
Ease of Printing
PETG is one of the easiest-to-print materials out there. It adheres well to most build surfaces, does not tend to warp, and has a wide optimal temperature range.
ASA requires more controlled printing conditions like an enclosed chamber and dialed-in temperatures to prevent warping. Still, ASA is not as finicky to print as original ABS.
ASA vs. PLA Filament
PLA is by far the most common beginner 3D printing filament. Here’s how it differs from ASA:
Temperature Resistance
PLA has a very low deflection temp around 60°C. Parts printed in PLA will quickly deform in hot environments.
ASA can withstand temperatures up to 105°C, making it suitable for outdoor or automotive applications where PLA would fail.
Weathering Resistance
PLA has poor UV resistance and will show noticeable degradation in sunlight over time. ASA retains its mechanical properties and appearance much longer thanks to its acrylic component.
Mechanical Strength
While suitable for low-force applications, PLA lacks the durability, impact resistance, and tensile strength of engineering-grade materials like ASA. ASA can produce long-lasting parts able to withstand years of mechanical stresses.
Ease of Printing
PLA is the easiest 3D printing material to work with by far. ASA requires an enclosed chamber and dialed-in extruder temperatures to print successfully.
ASA vs. Polycarbonate (PC)
Polycarbonate is another high-performance engineering filament like ASA. Here are some key differences:
Temperature Resistance
PC has the highest heat deflection temperature, around 130°C. This gives it better thermal stability than ASA for extremely hot applications.
Weathering Resistance
Untreated PC will degrade faster in sunlight than ASA. However, PC can be manufactured with UV inhibitors that give it excellent weatherability.
Mechanical Strength
PC has very high tensile and impact strength. It’s one of the toughest engineering thermoplastics available. Both PC and ASA can produce durable parts, but PC has a slight edge.
Ease of Printing
PC is notoriously tricky to print and master. ASA is easier to print thanks to lower extrusion temperatures and less warping.
ASA Filament Key Benefits and Drawbacks
Now that we’ve compared ASA to common 3D printing filaments, let’s summarize some of its major advantages – and potential limitations:
Key Benefits of ASA Filament:
- Excellent temperature resistance up to 105°C
- High UV/weathering resistance for outdoor use
- Good strength and impact resistance
- Easy to post-process and finish
- Less prone to warping than original ABS
Potential Drawbacks of ASA:
- More difficult to print than PLA or PETG
- Properties not quite as good as advanced engineered plastics like PC
- Lacks transparency of acrylic (PMMA)
- Can still require enclosure to prevent warping
So in summary, ASA combines excellent mechanical properties, heat resistance, and UV stability into one package. It bridges the gap between commodity plastics like ABS/PLA and truly advanced engineered materials.
Best Uses for ASA Filament
Thanks to its well-balanced set of properties, ASA is a great choice for:
- Outdoor applications like tool housings, enclosures, and components that require weather resistance
- Automotive parts and aftermarket accessories that must withstand hot engine environments
- Functional prototypes needing good thermal stability and mechanical strength
- Low-volume production parts such as drone components or scientific tools
- Applications requiring post-processing like painting or machining
ASA offers engineers a production-grade material for demanding use cases in 3D printing. It improves upon some of the drawbacks of traditional ABS while avoiding the difficulties of highly engineered plastics.
ASA Filament Printer Settings
To achieve optimal prints with ASA material, use these recommended slicer settings:
- Nozzle Temperature: 240-260°C
- Heated Bed: 90-110°C
- Print Speed: 40-80mm/s
- Cooling Fans: Off
- Chamber Temperature: 45-60°C
- Adhesion Method: ABS/ASA slurry or adhesive
- Nozzle Type: Hardened steel required
Key things to note are the high nozzle temperature required, the heated chamber to prevent warping, and use of a substrate adhesion method.
An enclosed 3D printer fitted with an active heating chamber is strongly recommended for ASA printing. Leaving the chamber door open or using strong cooling fans is likely to cause warping and layer separation. Dialing in the optimal temperature settings and adhesion method will produce the best ASA print results.
Finishing ASA Printed Parts
One of ASA’s advantages is that printed parts can be post-processed in various ways:
Sanding – ASA sands smoothly, allowing removal of layer lines for a smooth finish. Start with coarse grit sandpaper and work up to fine grits.
Painting – ASA adheres very well to paints and primers. Lightly sanding first will help paint stick. Use spray paints designed for plastics.
Polishing – Acrylic or ABS plastics polishes can bring ASA parts to a glossy shine. Polishing helps smooth the surface.
Machining – ASA can be tapped, drilled, and machined with traditional tools. Allow for 15-20% shrinkage if precision is needed.
Modifying and finishing ASA 3D printed parts is easy with standard plastics working techniques. The smooth surface gives excellent results for painting and polishing.
Where to Buy ASA Filament
ASA filament is growing in popularity and availability. Here are some top brands to look for:
- Prusament ASA – Made in an ISO certified factory with tight dimensional tolerances. Excellent consistency.
- MatterHackers Build Series ASA – USA-made with precise diameter and strict quality controls.
- Polymaker ASA – Known for high-performance engineering filaments. Polymaker ASA offers excellent interlayer adhesion.
- 3DXTech ASA – Produced in Michigan with tight dimensional tolerances (+/- 0.03mm).
- eSUN ASA – Economically priced ASA with high impact resistance and tensile strength.
Premium ASA filament brands like Prusament and Polymaker offer very consistent, precision filament ideal for critical applications. Economical brands can be suitable for less demanding prints.
The Future of ASA Filament
ASA has already grown into one of the most popular materials for high-performance FDM 3D printing. As more consumers and industries adopt 3D printing, ASA is likely to continue gaining users thanks to its engineering-level properties.
Material innovation will also continue expanding the capabilities of ASA:
- Specialty colors like neon or translucent ASAs for custom carbon fiber aesthetics
- ASA composites reinforced with carbon fiber or glass fiber for increased stiffness and strength
- Hybrid ASA blends that enhance properties like thermal resistance or toughness
- Improved resistance to hydrolysis and chlorine for plumbing and chemical applications
ASA offers the perfect base material for composite and specialty filament manufacturers to innovate upon. The acrylic-ABS chemistry provides balanced mechanical properties ideal for reinforcement or modification.
As technology improves, expect ASA to become accessible to wider audiences of designers, engineers, manufacturers, and 3D printing hobbyists needing its rugged performance.
ASA vs. ABS vs. PETG vs. PLA: Conclusion
Thanks to its well-rounded set of properties, ASA filament is emerging as a top choice for advanced FDM 3D printing applications. It combines the strength of ABS with enhanced thermal stability and UV resistance.
While not as easy to print as PLA or PETG, ASA offers engineering-level capabilities exceeding those commodity plastics. It also avoids some of the challenges of highly engineered materials like PC.
The excellent blend of strength, toughness, heat resistance, and weathering resistance make ASA ideal for demanding applications from outdoor usage to automotive parts. As material innovation and printer technology progress, ASA is likely to continue growing as a next-generation filament of choice.
