PLA (Polylactic Acid) and ABS (Acrylonitrile Butadiene Styrene) are two common 3d printing materials. ABS filament is slightly more expensive but produces stronger and more durable prints. PLA is generally easier to work and produces more aesthetic-looking parts.
Since both are common materials in 3D printing, you may wonder which 3D printing filament you should use for your project.
With over ten years of experience with PLA and ABS filament, we’ll look at the differences between PLA and ABS to help you decide which is best for your project.
Material Comparison of PLA vs. ABS
PLA is favored by hobbyists and professionals for its ease of use, reliability, low cost, and high print quality. The easy-to-use nature of the filament makes it ideal for beginners. And it’s low melt point and easy-to-use properties of PLA make it compatible with most 3D printers.
However, PLA lacks mechanical strength and is unsuitable for high-heat environments or outdoor use, as it can warp and discolor.
PLA is biodegradable under industrial composting conditions but degrades slowly in nature. It’s made from crops like corn and sugar cane, processed into filament.
Poor storage of PLA 3D printer filament can lead to moisture absorption, causing printing defects. You can dry wet filament to restore its print quality.
In contrast, ABS is chosen for its durability and mechanical performance. ABS plastic is commonly used in injection molding and 3D printing for high-strength applications.
ABS filament is more difficult to use than PLA, requiring higher nozzle temperatures and an enclosure to avoid warping. You must also take more safety precautions as ABS emits toxic fumes during printing, posing safety concerns.
PLA and ABS have similar tensile strength. However, ABS is more robust due to its higher durability and ductility.
Temperature Settings
PLA requires a lower printing temperature between 190°C and 220°C and a bed temperature around 60°C. ABS, on the other hand, requires a slightly higher print temperature, ranging from 210°C to 250°C, and a bed temperature between 80°C and 130°C.
Both filaments are considered low-temperature printing filaments and are compatible with most hobby 3D printers.
You don’t need to print either filament at a high temperature. We recommend the lowest nozzle temperature that allows for layer adhesion to avoid heat creep.
However, ABS filament is prone to warping and shrinking as the filament cools on the print bed. You’ll want to print with an enclosure to prevent warping, as the enclosure slows cooling and prevents shrinkage.
Bed Adhesion
Bed adhesion plays an essential role in the success of your 3D prints. You’ll have a bird’s nest if the part doesn’t stick to the print bed.
When looking at the ability of the prints to stick to the build plate, PLA has far greater bed adhesion than ABS.
When printing in PLA, it is recommended to have a heated build plate, but it isn’t required. If you struggle to get your PLA to stick to the bed, you can use bed adhesives like painter’s tape or glue.
On the other hand, ABS requires a heated build plate. Otherwise, you won’t get any bed adhesion.
I have had many successful PLA prints with the heated bed turned off, but I cannot say I’ve never succeeded with a cold bed and ABS, even with bed adhesives.
If you are struggling to get ABS to stick to your bed, there are a few things you can try out.
- Turn off your part cooling fan. ABS needs time to let the layers set into the bed. Setting the cooling fan to 0% allows more time for layers to bond to the print surface.
- Use an enclosure. A 3D printing enclosure ensures a consistent ambient temperature, minimizing shrinking and promoting bed adhesion.
- Use a PVA glue stick. ABS doesn’t like to stick well to glass build surfaces. PVA glue is our preferred bed adhesive when working with ABS. We find great surface adhesion, and it’s easy to remove prints.
- Use Hairspray. Hairspray creates a slightly rougher and stickier surface for the material to adhere to. Hairspray doesn’t affect the part’s surface finish but will help it stick to the bed better.
Print Quality
PLA is popular for its incredible print quality. PLA filament is easy to work with, and even beginners can achieve excellent results with the default profiles in your slicing software.
If your printer is level and set up correctly, you won’t have any significant issues printing PLA.
ABS is much more difficult to work with. As we mentioned earlier, ABS filament is prone to warping and shrinking.
As a result, it’s much more difficult to achieve a high print quality with ABS. Even with a perfectly tuned 3D printer, it’s nearly impossible to match the print quality of PLA.
As ABS plastic cools, it’s more likely to pull away from the print bed, causing adhesion issues. Additionally, if the layers cool too quickly, the molten filament won’t bond to the previous layer, causing gaps between the layers.
Printing with ABS filament requires a properly calibrated 3D printer, enclosure, and finely tuned slicer settings.
Even experienced makers struggle to get good results with ABS filament. We only recommend printing with ABS once you’ve gained experience printing with PLA.
Post Processing Techniques
Experimenting with hot acetone vapor smoothing of PLA
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Post-processing your 3D prints helps transform them and take them to the level of a finished product.
I find that both PLA and ABS respond similarly to sanding, filling, and painting.
You can achieve excellent results with either plastic with enough time and patience.
When sanding PLA, you must be careful using an electric sander. PLA has a low melting point. The heat generated from the friction of an electric sander is enough to soften the plastic.
If you use an electric sander, ensure you keep the sander moving around the part. Don’t sand one place too long, or you’ll risk heating the plastic.
ABS is more forgiving as it has a higher glass transition temperature of 105°C.
Although I generally find PLA easier to sand and smooth, ABS has the advantage of vapor smoothing.
Vapor smoothing is a process that involves placing the ABS part in a sealed chamber with acetone vapor. The acetone vapors slightly dissolve the surface, smoothing out imperfections and print lines.
Acetone is chosen because ABS acetone is insoluble. The duration of exposure varies based on desired smoothness and part size. After treatment, the 3D printed part exhibits a glossier and smoother finish.
However, acetone smoothing can affect the part’s dimensional accuracy and mechanical properties. You also must take safety precautions due to acetone’s flammable and toxic nature.
Environmental Impact
PLA is renowned for its eco-friendliness, primarily due to its biodegradability. PLA plastic is derived from renewable resources like corn starch or sugarcane, allowing it to break down more easily than traditional plastics.
However, PLA requires specific industrial composting conditions for efficient decomposition and does not degrade quickly in nature or in landfills.
Thanks to its plant-based origin, PLA consumes less energy to produce, leading to a lower carbon footprint.
Additionally, PLA is safer for indoor use compared to ABS as it emits a relatively low level of ultrafine particles (UFPs) and volatile organic compounds (VOCs). It’s generally viewed as a safe filament, posing less risk to users and the environment. You don’t need advanced filtration when printing PLA, though we always recommend using an air filter when possible.
ABS filament has a worse environmental impact. Although ABS plastic is recyclable, it isn’t biodegradable.
The production of ABS is more energy-intensive, reflecting its petroleum origins and resulting in a higher carbon footprint.
ABS emits high UFPs and VOCs, which can be harmful if inhaled. It’s essential to have proper ventilation and an enclosure due to the harmful toxins released during the 3D printing process.
Applications: Which Should You Choose?
PLA is the best choice for beginners, cosmetic items, and indoor applications.
PLA filament’s low shrinkage, low cost, and excellent print quality make it a perfect option for decorative items and prototypes. However, due to its low heat resistance and low durability, PLA is not suitable for outdoor use or applications that require temperature and
Choose ABS when making parts for high-temperature and high-wear applications. ABS has higher flexural strength and is more impact-resistant compared to PLA.
