Before even considering using ASA, make sure your 3D printer meets the following hardware requirements. This will definitely save you a headache in the future.

• Heated bed: This is mandatory. ASA is prone to shrinking and cracking due to the temperature difference between the nozzle and the surrounding air. The thermal deformation caused by this disparity creates internal tensions that potentially lead to problems during the printing process.
• Build surface: Proper bed adhesion is essential for ASA, and for this, there are dozens of solutions. Many use Kapton tape, coating solutions such as ABS glue, or standard hairspray. As with any other material that depends on good bed adhesion, make sure your bed is always properly leveled.
• Enclosed printer: This is highly recommended, especially when printing large parts. Though it’s possible to get away with printing smaller parts without an enclosure, larger models will produce a lot of residual stress that can eventually cause cracking and delamination. An enclosure also protects the 3D printer from drafts that will most certainly cause parts to warp.
• High-temperature hot end: No special hot end is required as long as it can print at temperatures as high as 260 °C. PTFE-lined hot ends might not be suitable for longer periods of ASA printing since PTFE starts degrading at 250 °C. While some ASA filament brands can be printed with temperatures lower than 250 °C, an all-metal hot end is surely the safer choice.
• Filament storage: ASA is hygroscopic, meaning it absorbs moisture from the air. This moisture can cause extrusion inconsistencies and surface defects, among other issues. Therefore, it’s important to store ASA in a dry box.

If all the hardware requirements are met, it’s time to fine-tune the print settings:

• Bed temperature: For ASA, it’s recommended to have the build plate temperature set between 90 and 110 °C, depending on the filament brand. Be sure to let it sufficiently preheat before starting a print (this will also heat the print chamber).
• Nozzle temperature: This material prints at a relatively high temperature, usually falling within the 240 to 260 °C range. Generally speaking, go higher when you notice poor layer adhesion and go lower if you notice sagging bridges, stringing, or oozing. It’s suggested to decrease the temperature for the first layer by 5-10 °C.
• Print speed: Generally, the best speed for printing ASA will be between 40 and 50 mm/s. To help improve bed adhesion, you can try printing the first layer at 25 mm/s. Reduce your print speed if you’re noticing layer adhesion issues.
• Cooling: No cooling is required for printing with ASA. In fact, it’s generally recommended to leave it off. However, very low speeds (5 to 10%) might improve overhangs and overall print quality. We suggest first focusing on having good layer adhesion, and once that’s achieved, try using the cooling fan to avoid overheating issues.

Other settings, such as layer height and infill, will depend on your specific printer, filament, and project. We suggest using the default settings for your specific filament brand and tweaking them to suit your needs.

For example, if you’re going for functional parts that need high strength, you may want to use upwards of 50% infill, however, using much higher infill content can make the part more prone to warping. The infill pattern can also help increase your print’s strength. You can get away with 20% infill for aesthetic prints, but don’t go lower as the part will be more susceptible to cracking.

Printing with ASA can have its difficulties because it can be terribly sensitive to temperature changes. The good news is that ASA is still easier to print with than ABS.

As mentioned earlier, perhaps the most pressing issues when working with ASA are the warping effects and the potentially dangerous fumes that can be released.

Warping

Warping happens when the part fails to cool evenly. There’s plenty of information on avoiding warping during FDM printing, which is mostly with ABS. And since these two materials are so similar, it’s a good idea to follow the same recommendations: avoid wind drafts, ensure good first-layer adhesion, keep your printer calibrated, and use brims or rafts.

Fumes

As for the fumes, most printing materials release some kind of harmful substance during extrusion. Perhaps the most famous one is ABS, known to emit both dangerous gaseous molecules and nanoparticles. Although less troublesome than ABS, printing with ASA can be a very smelly process – mostly due to the presence of styrene. However, if you’re noticing strong smells, you may want to decrease the printing temperature slightly.

Proper ventilation is strongly recommended along with the use of masks, if appropriate.