PSU vs ASA
Compare PSU and ASA filaments side-by-side. See which one is best for your 3D printing project.
PSU
BPolysulfone
Very high heat resistance (Tg ~187C) and retains strength near that range
ASA
AAcrylonitrile Styrene Acrylate
Excellent UV resistance (outdoors indefinitely), tough, matte surface
Detailed Comparison
Property
PSU
ASA
Tier Rating
Tier B
Tier A
Family
PSU
ASA
Nozzle Temp
340-380°C
220-275°C
Bed Temp
140-180°C
90-110°C
Enclosure
required
recommended
Cooling
Low cooling
Low to moderate; avoid drafts
Moisture Sensitivity
moderate
moderate
Strengths Comparison
PSU Strengths
- Very high heat resistance (Tg ~187C) and retains strength near that range
- Resists water/radiation/chemicals; can be sterilized
- Enables 'citizen science' type projects
ASA Strengths
- Excellent UV resistance (outdoors indefinitely), tough, matte surface
- Less warping than ABS; low viscosity enables very high speed printing
- High heat tolerance (~boiling water range)
Considerations
PSU Caveats
- Often nylon is a better overall choice unless you need the heat/sterilization envelope
ASA Caveats
- Still off-gasses; enclosure/ventilation recommended
- Can still warp; needs tuning
Frequently Asked Questions
Is PSU or ASA better for 3D printing?
ASA is generally rated higher (Tier A) compared to PSU (Tier B). However, the best choice depends on your specific needs: PSU is best for Very high heat resistance (Tg ~187C) and retains strength near that range, while ASA is best for Excellent UV resistance (outdoors indefinitely), tough, matte surface.
What are the temperature differences between PSU and ASA?
PSU prints at 340-380°C nozzle / 140-180°C bed. ASA prints at 220-275°C nozzle / 90-110°C bed.
Do PSU and ASA need an enclosure?
PSU: required. ASA: recommended.
Which is more beginner-friendly: PSU or ASA?
Neither is particularly beginner-friendly - both typically require an enclosure.