3-D printing in plastic uses spools of plastic string (filament) as the raw material. The filament is melted and extruded layer by layer to build up the 3-D shape that you want manufactured. Different filaments have different characteristics that make them suitable for particular purposes.
Common filaments we print with include PLA, PETG, ABS, HIPS, TPU, PC.
PLA – Polylactic Acid – easy-to-print, plastic made from corn starch, biodegradable. Comes in hundreds of colors and variations, PLA+, PLA-HT. Good for models and figures especially where mechanical or temperature resistance aren’t needed.
PETG – Polyethylene Terephthalate modified with Glycol – higher temperature resistance, used for printing technical and mechanical parts. Glossy surface, doesn’t shrink or warp.
ABS – Acrylonitrile Butadiene Styrene – Opaque, high temperature plastic, strong mechanical properties. Releases fumes, tends to curl.
HIPS – High Impact Polystyrene – lightweight, strong, structural plastic, relatively high temperature.
Flexibles (TPU, TPE) – Thermo Polyurethane/Thermoplastic Elastomer – Rubbery materials with a high elasticity. Used for bumpers, flexure joints, traction surfaces (tires).
PC – Polycarbonate – high-temperature, very strong, nearly transparent, very hygroscopic.
Each of these filaments requires different storage conditions, handling, nozzle temps and bed temperatures, bed surface/treatment (PEI, PVA, ABS slurry) to print successfully.
For those who are doing your own 3-D printing, consider a Maker Box subscription (several options for amount and frequency) which will get you a wide variety of colors, mostly PLA, but a variety of other materials included as well.
The first step of 3-D printing something out of plastic is to define or get a 3-D model of the object you would like to print. To define the object you would use 3-D CAD (Computer-aided Design/Drafting) software like OpenSCAD, Autodesk Fusion 360, SketchUp, or OnShape that allow you to design your object and export the result as an .STL file. Alternately, you can search an find a part that has already been designe that also meets your needs. There a numerous 3-D model repositories and index sites online where you can download (free and paid) models to print.
Once you have your desired object defined, it will be loaded into software called a slicer (we use PrusaSlicer) that will break the 3-D object into a series of discrete layers and generate the step-by-step instructions for the 3-D printer to follow to create the object. There are many variables (layer height, perimeters, infill type, infill density) and configurables (support, rafts, brims) that can be modified in the slicer to get the exact print result you want. The output of the slicer software is a .gcode file containing all the instructions.
This .gcode is then loaded onto the 3-D printer along with the desired filament and the printer is given the instruction to start printing. The printer will heat up the bed and nozzle, the step through the instructions (gcode) created by the slicer. Depending on the size of the object, the layer height, density of infill the printing of your object can take anywhere from tens of minutes to tens of hours or even multiple days.
Once the print is finished the printer will cool down and the print will be removed from the print bed. Any necessary post processing (removing supports, sanding surfaces, finishing, painting) would then be performed. This process ends with a 3-D plastic model of the object you designed or selected.
While the capabilities of 3-D printers continue to increase and prices continue to decrease, we realize that not everyone wants to do every step of this process. We can help by performing any or every step of this process for you, or we can assist you in any area where you need help.
I’ll defer to the great articles Prusa published on their site on this subject, but the short version is: 3-D printed plastic should not generally be used for storing or handling food products. There are far too many microscopic nooks and crannies for germs to get into that cannot be cleaned properly.
layer.works is a full-service 3-D design/make/teach service provider, based in Central Alabama.
We do custom prototyping, mass production, training, troubleshooting, and consultation in additive and subtractive manufacturing.
If you have 3-D printing, 3-D design, or large-format CNC (4×8 foot) needs, send us an inquiry and we’ll get back to you quickly. Not sure if we can help you? Drop us a line with your needs and we’ll figure out what we can do or point you in the right direction.