Your Guide to Large Scale 3D Printing With ASA Filament

With so many 3D printing filaments on the market, it can be challenging to find the perfect material for a given application. At the same time, the wide variety of filaments means that 3D printing is viable for more applications than ever, whether it’s assembly fixtures for the aerospace industry or industrial-grade end-use parts for automotive applications. 

BigRep, known for its industrial large-format 3D printers, offers a range of engineering-grade filaments optimized for its machines, from PLA variations to carbon-fiber-reinforced thermoplastics. In this article, we’re looking at BigRep ASA, a heavy duty filament ideal for outdoor use.  

What is ASA 3D printing filament?

ASA (Acrylonitrile Styrene Acrylate) is a thermoplastic filament known for its high strength and weather resistance. The engineering-grade material bears many similarities to ABS, one of the most widely used 3D printing filaments, but has some distinct advantages. Similar to ABS, ASA is characterized by good temperature resistance, high impact resistance, and toughness. Where ASA starts to stand apart from ABS is when we look at weather resistance, and specifically UV resistance. 

BigRep ASA filament is engineered to withstand UV exposure and is therefore ideal for outdoor applications, like automotive components, consumer goods, sporting equipment, and more. The robust thermoplastic filament also offers a range of other beneficial properties when 3D printing, including a low rate of shrinkage and good layer adhesion. 

Why Use BigRep ASA filament? 

BigRep ASA is a good fit for many applications, like functional prototyping, tooling, and end-use parts. Optimized for BigRep’s large-format 3D printing—and specifically the BigRep STUDIO G2 and BigRep PRO 3D printers—the filament is particularly handy for making large parts (up to 1020 x 970 x 985 mm) that are used in outdoor environments or are exposed to sun and heat. 

In addition to its UV and weather resistance, ASA filament demonstrates excellent impact strength (30 kJ/m²) and good heat resistance. For instance, BigRep ASA has a Heat Deflection Temperature (HDT) of up to 86 °C, meaning that printed parts will not deform under certain loads below that temperature. Ultimately, if you’re looking for a material with similar properties to ABS but with superior mechanical properties, aesthetics, and UV resistance, ASA is it. 

Benefits of 3D Printing BigRep ASA

Among the main benefits of 3D printing BigRep ASA are the material’s high UV stability, impact resistance, and heat resistance. Compared to ABS, ASA filament is also easier to print: it tends to warp less and can be post-processed using mechanical methods like sanding or drilling, as well as chemical smoothing methods, like acetone vapor. When printing ASA, it is possible to achieve high quality surface finishes that will last through various climates and weather conditions.

In order to unlock the most benefits from BigRep ASA filament and maximize the material’s properties, it’s important to use the right combination of print settings. BigRep recommends the following print temperature and print speed ranges for its ASA material:

• Nozzle temperature: 200 - 240 °C

• Print Bed Temperature: 40 - 80 °C

• Chamber Temperature: n/a

• Print Speed: >40 mm/s

What to Look Out For When 3D Printing BigRep ASA

As we saw, BigRep ASA has numerous benefits, but the material also comes with a couple of challenges. Fortunately, these can be easily overcome by simply adjusting print settings and implementing some print preparation techniques.

The main issue you may encounter when 3D printing ASA filament is warping. Like ABS, ASA is prone to warping on the print bed. This is the result of the printed part cooling too rapidly or unevenly, which causes the material to shrink and pull up from the print surface. The first line of defense against ASA warping is to use a print bed adhesive, such as BigRep Kapton print bed foil and/or Magigoo glue. You can also minimize warping by slowing down the print speed in the first layers of your build. This will help to ensure strong first layer adhesion as the printer deposits more and more layers.

Material Properties 

To better understand ASA’s material properties, we’re going to take a quick look at the thermoplastic’s mechanical, thermal, and chemical properties.

Mechanical properties

Starting with ASA’s mechanical properties, the material is known for its high impact resistance and strength. ASA boasts a higher tensile strength (40 MPa) than standard ABS (30 MPa) as well as a superior tensile modulus (1900 MPa) than ABS (1400 MPa). Put another way, ASA is more ductile than ABS and can withstand greater stresses without breaking. 

Thermal properties

In terms of thermal properties, ASA has good heat resistance with an HDT of up to 86 °C. Like ABS, the filament does require relatively high nozzle temperatures for the optimal printing results, typically around 215 °C, as well as a heated print bed (40 - 80 °C). 

Chemical properties

One of ASA’s main selling points is its resistance to UV exposure. In addition to this, the material is also resistant to many chemicals, including certain acids and oils. ASA is also known for its anti-static properties, which make it suitable for electronic applications.

Best Practices for Storing and Handling BigRep ASA 

You can make the most out of BigRep ASA by following proper storage and handling guidelines. In terms of storage, ASA is fairly low maintenance and can easily last upwards of a year under the right conditions. In this case, the right conditions consist of a dark, ambient environment that is protected from moisture. 

A dry environment is important because ASA is somewhat hygroscopic, meaning it absorbs moisture from the air. In order to preserve the quality of BigRep ASA spools, you should therefore store the material in a dry room or a sealed container with desiccant. (That said, ASA is less hygroscopic than other common filaments like PLA and Nylon, so it may not be as critical to dry it if it is briefly exposed to humidity.)

ASA filament does not come with any serious health warnings, but significant exposure to fumes created in the printing process can become hazardous to users. To avoid any potential health risks associated with 3D printing ASA, ensure you are 3D printing in a well-ventilated space. If you are running a 3D print farm or a multi-printer operation, for instance, it’s a good idea to install a local exhaust ventilation system. 

Use Cases: See How Customers Use BigRep ASA 

BigRep ASA has been enthusiastically adopted by a range of industries, but perhaps none more than automotive. The material’s high strength, as well as its resistance to impact, high temperatures, and weather, have made it a popular option for printing automotive end-use components as well as jigs and fixtures for automotive manufacturing and assembly processes. 

Zoeller-Kipper, a specialist in waste disposal technologies, has adopted BigRep 3D printing to produce bespoke modifications for waste disposal vehicles. Thanks to its durability and ability to withstand UV exposure, ASA has been a perfect fit for its needs. In one use case, for example, Zoeller-Kipper 3D printed a large ASA part to be mounted on the rear corner of a garbage truck. The end-use part, which weighed 1,824 grams, was printed on the BigRep PRO and was ready within just two days.

Other uses for ASA in the automotive industry include jigs and fixtures, brackets, mirror housings, and manifolds. Outside automotive, ASA is also a popular material choice for 3D printing electronic enclosures, sporting equipment, parts for the maritime industry, and more. 

For more specifications on BigRep ASA or to purchase a spool of 2.85 mm filament, head to the BigRep Online Shop.