If you are about to embark on creating things with your new printer, it might be a good idea to learn something about your new paints, namely the plastic that you’ll be using.
Choosing your Plastic
Currently there are two common types of plastic used in 3D printing – PLA (Polylactic Acid or Polylactide) which is plant starch based and ABS (Acrylonitrile Butadiene Styrene) which is petroleum based. Both PLA and ABS have pros and cons. One or the other may be better for your situation. For example, ABS requires higher temperatures to extrude than PLA. That often requires that you use a hot plate to print on so the part does not cool too fast as it is being printed. PLA, on the other hand, frequently prints better if there is a fan blowing on the part to cool it down before it can droop.
PLA is made from plants rich in starch like sugar beets, corn and wheat. It is both commercially 100% compostable and 100% biodegradable. Compostable means that it can be broken down into water, carbon dioxide and biomass, will not produce any toxic material and can support plant life. Biodegradable means that it can be broken down over time through a process involving microorganisms (fungi or bacteria). However, the process can create methane at a rate 62 times the global warming potential of carbon dioxide.
ABS is a petroleum based plastic and not safe to use for products which may come into contact with food.
- More brittle than ABS
- Can droop if it gets too hot, for example, if it is left in a hot car in the summer time
- Usually turns white along the high stress zone when it is bent, then breaks into lots of little pieces
- Even though it is made from plants, it may contain dyes and binders which are not food safe
- Smells sweet when it is being printed
- Strength is relatively equal to ABS
- Impact resistant and tough
- Petroleum based
- Prone to cracking if cooled too quickly
- Usually bends before it breaks
- Has a strong, toxic smell when it is being printed
- Strength is relatively equal to PLA
ABS usually needs a fully up to temperature heat bed or the part may not work. PLA , on the other hand benefits from cool blowing air to keep its temperature down so it does not droop. But it can also benefit from a heated printbed.
Many people have had good results printing ABS on Kapton, a form of Polyimide tape which is surprisingly expensive. But it usually lasts a long time. PLA , on the other, hand can often print right onto borosilicate glass. Some people find that PLA works great unheated on blue painters tape but the tape needs to be replaced fairly frequently.