What is printing filament?
Filament is the term that is used to describe the material that Fused Deposition Modelling (FDM) printers use to print with, these are the ones . It is usually made up of either ABS or PLA plastics. PLA is short for Polylactic acid or polylactide and ABS is short for Acrylonitrile Butadiene Styrene, both quite big, scary words! Let’s break each of these down.
Both ABS and PLA are thermoplastics, this means that when heated they become soft and malleable, but as soon as they cool down they become hard again. This is perfect for 3D printing, as when the plastic is extruded from the nozzle it needs to be soft, then as soon as it has been placed at the necessary position, it needs to harden immediately.
PLA is fully biodegradable, being made from corn starch and other plant products, although it needs to be sent to a commercial compost facility rather than in your own home. This is great for the environment, but PLA has quite a low melting temperature, so objects that are printed using this plastic can start to melt in even moderately hot conditions. This makes it unsuitable for heavy duty printing, but prototyping should be fine.
ABS however, is much more hardy, having a much higher melting point, it is also more flexible and generally stronger. Because of this it can be machined after print, ie. sanded or cut and shaped. This makes it the preferred material for engineers and most product designers. Sadly, its fumes do smell and can make you ill if you do not have a room with ventilation.
Filament is usually sold on spools that contain between 5 and 10 meters of the plastic in a long thin thread that is either 1.75mm or 2.85mm wide, the thickness depends on what brand of 3D printer you are using. Some 3D print brands use their own proprietary filament rather than the general open source stuff. They claim that this is to stop bad prints through badly mixed plastic, some companies even encase the filament to make it more like standard ink cartridges on your normal 2D printer.
The basic ABS or PLA can be mixed with other powdered materials like wood or ceramic to get different textures, like bamboo or stone. Like most plastics it can come in thousands of different colours and in the case of PLA, some manufacturers have even added scents into the material, so you can print and deodorize your room at the same time! The amount of options is huge and the best thing to do is to have a play around and see what works for your specific project.
New materials to print with are being invented all the time, check out ‘Ninjaflex’ for more rubberised prints, play around and have fun with it!