What is ABS?
ABS (Acrylonitrile Butadiene Styren) is a common thermoplastic, very popular for injection molding and it is used to make legos, instruments, sports equipment and much more. It is one of the most used materials in 3D printing community. It is a rather strong plastic when printed at correct temperatures. ABS also has a decent amount of flexibility meaning it will rather bend than break. Things that make ABS a great choice for printing are heat resistance, strength, impact resistance… In short it’s very good for most objects.
We recommend printing ABS at 220-245°C depending on your printer. Although you can print without a heated bed, it is very recommended you use one. The bed temperature should be somewhere between 70-100°C.
Leveling the bed is really important before starting a print. If the bed is too far from the nozzle the print simply won’t stick to the bed. If the nozzle is too close to the bed, it will block the extrusion, which might cause the nozzle to get jammed, and you don’t want that. Enclosing your printer is recommended to prevent ABS from shrinking rapidly, which might cause it to lift from the bed and ruin the print later on. Applying a good adhesive is also recommended to help your ABS print stick to the bed. We found that hairspray works just fine, but you can also use glue sticks or ABS slurry (dissolved ABS in acetone). When you apply hairspray onto your bed surface, raise the temperature of the bed and leave it for 10-15 minutes so the spray dries and sticks to the glass.
To get the first layer to stick to the bed successfully you should raise both bed and nozzle temperature for about 5-10°C. After the first layer is printed, reduce the temperature back to normal. We found that lowering the speed of the first layer also helps it to stick to the bed better.
ABS is known for its warping problems. A 100 mm model can shrink as much as 1,5 mm if it is cooled too quickly, which causes most ABS printed models to lift from the bed in the middle of the print. This is why a heated bed is almost a must when dealing with ABS. If the heated bed is not enough, enclosing a printer is a good solution. This way you will have a controlled ambient temperature with no draft and your ABS models will cool down slower.
Finishing and post-processing ABS prints
If you’re not satisfied with how your ABS print came out you can use some post-processing tricks to smooth it out and make it glossy. If you printed with supports you should remove as much of those as you can. Keep in mind that this method will work with ABS only, since other materials have different properties and need different post-processing tools. One of the easiest and most efficient ways to smooth out you ABS prints is with an acetone vapour. If your prints will come in contact with food or small children we do not recommend using this method, as ingesting these compounds could be dangerous. Make sure you do this in a well ventilated place or even better, do it outside. We like this method since it is relatively slow and you have control over you model.
What you will need:
- A base to put your print on
- An airtight container
How to do it:
- Start by removing as much of the excess material from your print.
- Pour a small amount of acetone in your container.
- Place your 3D print inside, making sure that it does not come in direct contact with acetone, as this will cause your print to dissolve completely.
- Close the lid
- Allow your print to sit for some time, until you’re happy with the level of smoothness.
- Take your print out of the container and let it sit for a couple of minutes to allow it to dry.
When to use
Because of its great properties ABS can be used to print everyday objects. Due to it’s good heat resistance you can print things such as phone cases, car phone mounts and cup holders, because the print won’t change shape or start to melt.
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