ASA (Acrylic Styrene Acrylonitrile) is a technical material that is considered a successor to ABS. Compared to ABS, ASA is more UV resistant, warps less, and doesn’t smell as much. ASA is a tough and resilient material that is, thanks to its UV and temperature resistance (up to 93 °C), suitable for outdoor use and for making technical parts. See for example our MK3S printer fan shroud. Another great advantage of ASA is its solubility in acetone vapors, which can be used to make a smooth and glossy finish. This gives the model not only great looks but also different mechanical properties (see our article about chemical smoothing).
The main disadvantage of ASA is significant warping caused by temperature differences between the model and its surroundings. Another disadvantage is that ASA releases potentially dangerous fumes during printing - this means you should keep your printer in a well-ventilated area. ASA can be easily sanded both wet and dry.
You can find more details about how to print with ASA in our in-depth article.
And to compare supported material properties, see our material table.
✔ High UV resistance
✖ Significant warping
✔ High temperature-resistance
✖ An enclosure is necessary for printing large parts
✔ Detailed prints with no stringing
✖ Potentially dangerous fumes (styrene)
✔ Possibility of acetone smoothing and gluing
✖ Prints at high temperatures
|✔ Easy postprocessing (e.g. sanding, cutting, etc.)
✖ Partially hygroscopic (absorbs moisture)
|✔ High impact and wear resistance
ASA is suitable for outdoor use and for making technical parts.
Try to keep a high ambient temperature
The bed should be heated to at least 100 °C, and the printer should be inside an enclosure to keep a higher ambient temperature. If you don’t have an enclosure, there’s one simple alternative: in PrusaSlicer, set the skirt value as high as possible. This will create a wall around the object and keep the model slightly warmer, mitigating the warping. Keep in mind that printing a lot of ASA in an unventilated enclosure can cause the fan shroud and/or extruder plastic parts to deform over time. This may impact performance or cause issues.
It is also possible to make your own enclosure.
Printing with HIPS
ASA sticks very well to our print sheets (smooth and powder coated) but other print surfaces, like glass, might require a layer of acetone with dissolved ASA (or ABS). If you print with MMU2S, you can use HIPS for printing supports - this material has similar print settings to ASA and can be easily dissolved in limonene.
ASA is a pretty good material for postprocessing. Not only you can sand it wet and dry but you can also glue/weld it with acetone and smooth it with acetone vapors. Smoothed models have a glossy surface that looks like it’s treated with car lacquer or was injection molded. However, printed objects usually tend to lose detail and sharp edges with smoothing. You can find out more about chemical smoothing in article about chemical smoothing.
|Acetone smoothed prints
|Fan shroud (high-temperature resistant parts)
|Outdoor (UV resistant) parts