Published on Wed May 22 2024 18:51:27 GMT+0000 (Coordinated Universal Time) by Alex

Prusa ASA Filament: A Deep Dive into Engineering-Grade 3D Printing

Acrylonitrile Styrene Acrylate (ASA) is an engineering-grade thermoplastic known for its superior UV resistance, toughness, and dimensional stability compared to more common materials like ABS. Prusa Research offers its own version of ASA filament, designed and optimized for consistent and reliable 3D printing. This article will provide a detailed look at Prusa ASA, covering its specifications, best practices for use, and overall assessment.

Prusa ASA: Key Specifications

• Material: Acrylonitrile Styrene Acrylate (ASA)
• Diameter: Typically 1.75mm ± 0.05mm (Prusa standard)
• Spool Size: Typically 1kg
• Recommended Nozzle Temperature: 240-260°C
• Recommended Bed Temperature: 100-110°C
• Density: ~1.05 g/cm³
• Tensile Strength: ~40 MPa (varies slightly based on print parameters)
• Elongation at Break: ~20% (varies slightly based on print parameters)

Understanding the Advantages of ASA

Prusa ASA offers several key advantages over other filaments, particularly ABS:

• UV Resistance: This is ASA’s standout feature. It’s significantly less prone to yellowing, cracking, and weakening when exposed to sunlight, making it ideal for outdoor applications.
• Mechanical Properties: ASA boasts good tensile strength and impact resistance, resulting in durable and functional parts.
• Dimensional Stability: ASA exhibits relatively low shrinkage during cooling, leading to more dimensionally accurate prints with less warping.
• Chemical Resistance: ASA resists many common chemicals, making it suitable for parts that might encounter solvents, oils, or cleaning agents.

Best Practices for Printing with Prusa ASA

Achieving optimal results with Prusa ASA requires careful attention to print settings and environmental conditions:

• Enclosure is Highly Recommended: An enclosure is crucial for printing ASA. It helps to maintain a consistent ambient temperature, preventing warping and cracking. A draft-free environment is essential.
• Bed Adhesion: ASA can be prone to warping, so excellent bed adhesion is vital. Use a textured PEI spring steel sheet, clean it thoroughly with isopropyl alcohol before each print, and consider using a brim or raft for larger parts.
• Print Temperature: Experiment within the recommended range of 240-260°C for the nozzle and 100-110°C for the bed. Find the optimal temperature for your specific printer and ASA spool. Lowering the bed temperature to 90-95°C after the first few layers can sometimes help prevent elephant’s foot.
• Cooling: While some cooling is necessary, excessive cooling can lead to layer adhesion issues and warping. Start with a very low fan speed (10-20%) for the first few layers, then gradually increase it if needed.
• Print Speed: A moderate print speed generally yields the best results. Start with around 40-60 mm/s and adjust as needed. Faster speeds can sometimes lead to layer adhesion problems.
• Layer Height: A layer height of 0.2mm is a good starting point, but you can experiment with different layer heights to optimize print time and surface finish.
• Proper Storage: Like most filaments, ASA is hygroscopic (absorbs moisture from the air). Store your ASA in an airtight container with desiccant when not in use to prevent printing issues caused by moisture absorption.
• First Layer Calibration: A properly calibrated first layer is vital for successful ASA prints. Ensure that the nozzle is the correct distance from the bed and that the filament is adhering well.
• Ventilation: While ASA produces fewer fumes than ABS, it’s still advisable to print in a well-ventilated area.

Troubleshooting Common ASA Printing Issues

• Warping: The most common problem with ASA. Ensure proper bed adhesion with good prep and a brim. Increase enclosure temperature, reduce cooling, and check nozzle to bed distance.
• Cracking/Delamination: Caused by uneven cooling. Ensure an enclosure, reduce cooling, and potentially increase the nozzle temperature slightly.
• Poor Layer Adhesion: Increase nozzle temperature, reduce print speed, and ensure the filament is dry.
• Stringing: Reduce nozzle temperature, increase retraction settings, and ensure the filament is dry.

Prusa ASA Filament: Detailed Rating

Here’s a detailed rating of Prusa ASA filament based on key performance characteristics, out of 10:

• Print Quality: 8/10 - Can produce high-quality parts with proper settings, but requires more dialing in than PLA.
• Toughness: 9/10 - Excellent impact resistance and durability.
• Flexibility: 3/10 - Relatively rigid material; not suitable for flexible applications.
• Warping: 5/10 - More prone to warping than PLA, requiring an enclosure and good bed adhesion.
• Adhesion: 7/10 - With proper surface preparation, provides very good adhesion.
• Moisture Sensitivity: 7/10 - Hygroscopic, requires proper storage.
• Color Range: 7/10 - Usually offers a decent range of colors.
• Temperature Range: 8/10 - 240-260C is the recommended printing range
• Odor & Fumes: 6/10 - Produces fewer fumes than ABS, but still emits a noticeable odor. Good ventilation is recommended.
• Spool Winding Quality: 9/10 - Prusa spools are generally well-wound, minimizing tangles and feeding issues.

Average Score: (8 + 9 + 3 + 5 + 7 + 7 + 7 + 8 + 6 + 9) / 10 = 6.9/10

Conclusion

Prusa ASA is a solid choice for 3D printing functional parts that need to withstand outdoor environments and mechanical stress. While it requires a bit more effort to print successfully compared to PLA, the resulting parts offer superior UV resistance and durability. With careful attention to print settings and proper storage, you can consistently produce high-quality ASA prints with Prusa ASA filament.

Written by Alex