Pellets, Powders, And Resins: Non-filament Plastic Used In 3D Printing
There are a few different forms of plastic that can be used in 3D printers: filament, pellets, powders, and resins. They each have different advantages and disadvantages.
You can’t use powders and resins with regular fused filament fabrication (FFF) 3D printers. But pellets can also be used with filament printers with some modifications to the machines.
For now, filaments are the most widely used. However, resins, pellets and powder printers are all gaining significant user bases. Someday one of these other types of plastic might be the industry standard.
Check out our complete guide to materials used in 3D printing.
3D Printer Filament: The Most Common Choice
Because FDM (or FFF) printers are the most popular desktop printers currently on the market, most 3D printers take filament.
3D printer filament are strands of plastic wire that go into a printer’s extruder. The extruder melts and extrudes the filament onto the print bed to form objects.
In comparison to 2D printers, filament basically acts as the ink of your 3D printer, except in three dimensions. There are many different types of 3D filament plastic available at the moment, and new types of filament are created practically every month.
Non-filament forms of plastic:
Pellets are simply unprocessed plastic beads straight from a manufacturer. They are usually processed into filament and then sold by filament manufacturers.
But you could skip that step and use the pellets instead of filament if you wanted to. And because pellets are the unprocessed form of the plastic, they are often much cheaper than filament. Plus you can buy them in bulk.
Some 3D printers use gypsum powder and binding material to create objects. Basically, a thin layer of gypsum is deposited on the printer bed.
Then a binding material is sprayed onto the gypsum in precise patterns. The binding material causes the gypsum to harden. Then the process is repeated. The object is created layer by layer.
Stereolithography (SLA) printers use resin and a laser to create objects. A pool of resin is hit by a laser that hardens the resin into a layer of polymer.
The laser then hits the resin again, hardening another layer of resin onto the previous layer. Over time, the successive layers build up to create an object.
Conclusion: So… why plastic?
At this point, you might be wondering why plastic is used so widely in 3D printing? After all, not everything is made of plastic. What about metal?
The answer is simple: metal printers are super expensive and plastic printers are cheaper. At the moment, 3D metal printers cost around $250,000 each.
Plastic filament deposition modeling (FDM) printers have steadily been dropping in price for the past 10 years. These days, you can get a plastic 3d printer for a few hundred dollars.
Meanwhile, metal 3D printers still cost thousands of dollars. There are many companies working on building affordable metal 3d printers. For instance, check out MatterFab.
But for now, most 3d metal printing is only affordable at an industrial level.