In the ever-evolving world of 3D printing, the type of filament you choose can have a significant impact on the quality, durability, and functionality of your printed objects.

There is no single “best” filament; rather, there is a right filament for different projects, each with its own set of requirements.

While Polylactic Acid (PLA) and Polyethylene Terephthalate Glycol-modified (PETG) were once the go-to materials, the rise in popularity of enclosed 3D printers has sparked greater interest in other materials that were once considered difficult to print with on open-format 3D printers.

These materials include ABS (Acrylonitrile Butadiene Styrene) and ASA (Acrylonitrile Styrene Acrylate). While both filaments share many similarities, their unique properties make them ideal for different applications.

In this article, we’ll compare ABS and ASA filaments to help you make an informed decision for your next 3D printing project.

ABS: The Established Player

Though often considered “old-fashioned” or difficult to print with in the era of PLA, ABS has long been a favorite among 3D printing enthusiasts. Common in injection molding and traditional manufacturing, this polymer is well-known for its strength, flexibility, and resistance to high temperatures.

As a petroleum-based thermoplastic, ABS is durable and relatively inexpensive, making it a popular choice for a wide range of applications. It is particularly valued for its ability to be easily sanded or vapor-smoothed after printing, making it ideal for projects requiring smooth finishes or intricate details.

Pros:

• Durability and Strength: ABS is known for its toughness, making it suitable for parts that need to withstand mechanical stress or wear and tear.
• Thermal Resistance: With a relatively high melting point, higher than PETG but lower than Nylon, ABS can withstand high temperatures without deforming, making it ideal for objects exposed to heat.
• Post-Processing Ease: It can be easily sanded, acetone-smoothed, and painted, allowing for high-quality finishes.

Cons:

• Warpage: ABS tends to warp or shrink during cooling, which can lead to print deformities if not managed properly.
• Ventilation Needs: It emits noxious fumes during printing, necessitating good ventilation or, ideally, a carbon pellet filter such as the Nevermore or Bento Box for safety.
• Printer Requirements: ABS requires a heated bed and an enclosed print area to manage its tendency to warp.

ASA: The Rising Contender

ASA is the superior choice for outdoor applications!

Although you may not have encountered ASA yet, it has been gaining popularity as a strong alternative to ABS, particularly for outdoor use. ASA is a copolymer of ABS and shares many of its strengths, but offers additional benefits, particularly in terms of UV resistance and weatherability.

ASA’s ability to withstand prolonged exposure to sunlight and outdoor conditions without losing color or material properties makes it an ideal choice for outdoor projects. Additionally, it is more impact-resistant, stronger, and heat-resistant than ABS.

Pros:

• UV Resistance: ASA is highly resistant to UV radiation, preventing discoloration and material degradation in sunlight.
• Printability: ASA is less prone to warping and emits fewer fumes than ABS, making it easier to print in some aspects (though not without some challenges, which we’ll cover in the cons section).
• Weather Resistance: It is more resistant to water, chemicals, and environmental factors compared to ABS.
• Aesthetic Finish: ASA prints often exhibit a smoother finish with fewer visible layer lines, and it is available in a wider range of colors.
• Strength: ASA is slightly stronger than ABS, particularly in terms of impact resistance (though still not as strong as Nylon).

Cons:

• Printability: While ASA is easier to print in some ways, it can be more challenging in others, due to its higher melting point and less favorable adhesion to the print surface compared to ABS.
• Cost: ASA tends to be more expensive than ABS, which could be a consideration for large-scale projects or budget-conscious users. However, this may change as production volumes increase.
• Ventilation: While ASA emits fewer fumes than ABS, it still produces fumes during printing, so proper ventilation is required.

Comparing ABS and ASA: Use Case Considerations

When deciding between ABS and ASA, it is crucial to consider the specific needs of your project. ABS is an excellent choice for indoor items that require strength and flexibility, such as functional prototypes, gears, and automotive components.

On the other hand, ASA’s UV and weather resistance make it the ideal choice for outdoor applications, including garden tools, automotive exterior parts, or signage that needs long-term color stability and material integrity.

Research conducted by engineers and material scientists at Stratasys has shown that ASA has slightly superior tensile strength, inter-layer adhesion, and IZOD impact resistance compared to ABS.

 

Printing Considerations

Both ABS and ASA require careful temperature management during printing. A heated bed is essential to prevent warping, and an enclosed printer is recommended to maintain a stable temperature. ABS typically prints at temperatures between 220°C and 250°C, while ASA prints at slightly higher temperatures, usually between 235°C and 260°C. For bed temperatures, ABS adheres well to most surfaces at 80-100°C without the need for glue stick, while ASA performs best at 90-110°C and may still require glue stick or hairspray for better adhesion.

Health and Safety

While ASA produces fewer fumes than ABS, the emissions from both filaments can be harmful if inhaled in large quantities. It is essential to use them in well-ventilated areas or with a filtration system. If using a carbon pellet filter, make sure to replace the pellets regularly, as they can become saturated quickly.

Conclusion

In summary, both ABS and ASA filaments offer distinct advantages for 3D printing. ABS excels in strength, ease of post-processing, and affordability, while ASA outperforms in outdoor durability, UV resistance, and weatherability.

 

The choice between ABS and ASA ultimately depends on the specific requirements of your project, such as environmental exposure, required durability, budget, and finish quality. With their unique properties, both ABS and ASA remain valuable tools for 3D printing enthusiasts and professionals alike.

About The Author:

Jonathan Levi is a YouTuber and 3D printing expert. In 2022, he founded The Next Layer and its YouTube channel, where he posts weekly videos about various interesting 3D printing projects and products.

If you have any questions about PCBs and PCBA, please feel free to reach out to me at info@wellcircuits.com.