Traditionally FDM 3D printing is done via the extrusion of plastic through a hot nozzle, melting layer by later until you create the Mona Lisa or another storage box to hold your other 3D printed items. What exactly is this plastic? And what properties does it have?
PLA (Polylactic Acid) PLA is the great value of 3D printing filament - it's cheap, it's abundant, it's easy to use, and it's very generic. PLA is also one of the more environmentally friendly of 3D printing filaments, being made from the fermenting process of things like corn and beets. As a result, it's fairly economical to come by, and it is a bio-degradable plastic (on the span of a few hundred years, but better than certain other plastics) PLA being so versatile allows you to make blends with other materials to change color or material properties. Add a bit of TPU and you have a semi-flexible material. Add some sawdust and you have a wood-feeling 3D print. Add some metal and you've got a (very brittle) but partially metallic print. Manhattan Makerspace maintains a stock of the whole rainbow of colors of PLA for rapid prototyping all manners of items exactly as wanted. Real world usage: Compostable packaging, cups, 3D printer filament, human body inserts
ABS (Acrylonitrile butadiene styrene) Try saying that 5 times fast. ABS plastic is another standard of 3D printing, though less common due to a number of reasons. Owing to its impact resistance and ability to stay in its form during hot days, ABS sees more rigorous usage in the world. As such, it is also more difficult to print on hobbyist printer (though more difficult in the sense of running 1 mile versus running 1.5 miles). Heated printer beds and enclosures aid in the printing process for these, and they're more often used for physical applications such as brackets, protective parts for drones, etc. Real world usage: Legos, automotive bumper bars, gold clubs, 3D printer filament
TPU (Thermoplastic Polyurethane) Probably one of the more interesting plastics in the hobby 3D printing space. TPU filaments come in a variety of grades depending on their flexibility. Whereas ABS and PLA are rigid plastics, TPU can range from only very slightly flexible like hard rubber, down to TPE filaments which have a lot of "squish" (a technical term). TPU is a more difficult material to print - it's bending can cause feeding issues in certain 3D printers, and as a result, are generally limited to direct drive extruders, or highly-tuned bowden-style extruders. The applications for this plastic are in various parts that require frequent deformation. Think of the hinge on a plastic box or a door stop - things that have to be deformed slightly to fit. TPU plastics also make for very interesting toys, flexible octopi and other such animals are very popularly printed items. Real world usage: Phone cases, drive belts, footware, inflatable rafts
PET/PETG (Glycolized Polyester) PETG filament is entering the
hobby 3D printing space in increasing amounts. While it requires a bit hotter temperatures than PLA, it also has increased structural strength and flexibility while still being easier to print than ABS. PETG also has the added interesting quality of having a wide range of transparency. PETG is a modified version of PET, which both are highly recyclable. You have have seen this plastic in your water bottles, which are nearly all PET. The G in the PETG allows for increased flexibility and reduced brittleness in the plastic. Real world usage: Everything from polyester yarn to water bottles to plastic cases
Nylons Nylons tend to be extraordinarily strong plastics despite thinness. Commonly seen in things such as fishing wire and weed-eaters, nylons also make up shirts, bags, and other things that need to be both light and rugged. Nylons are very uncommon in the 3D printing space, as it requires both a high temperature and is a hydroscopic material. This means that it takes on water from the environment, which combined with the above-boiling-point extruder of a 3D printer, creates errors in the print as the water very rapidly boils off. For certain high-strength applications, it's very useful, and some people have even been able to print with weed-eater wire. Real world usage: Nylon fibers (clothing, etc), food packaging, musical instrument strings
And that's our post for the day! 3D printing nowadays has a wide variety of materials at its disposal, with the only limits being time and build space. Thank you for the read, and let us know if there's any other content you'd be interested in hearing about!