3d Printing Materials
The materials that can be 3d printed seems to increase by the day. Initially there were only a couple of practical choices but now there are many. We find that for most projects a small selection of materials usually suffices. We are capable of printing more than what is in this list.
Filaments for FDM Printing
FDM printers melt filament fed from a spool and deposit the molten plastic in precise locations to build up a print.
Resins for SLA Printing
SLA printing creates a print by selectively curing a vat of resin. Not all resins have identical properties.
Polylactic Acid, or PLA, has been a standard on the 3d printing scene for years. It has the dual advantages of being economical and produced from renewable resources. PLA is a favorite as it is easy to print with reliable results. It is a solid choice for most objects.
PLA is a good all around choice for general applications. It is safe for use with food and drink and much disposable plasticware is made from it. It should not be used in high temperature applications as it becomes rubbery at a glass transition point of roughly 140 degrees Fahrenheit, and for items subject to a lot of mechanical stresses there are better options.
Polyethylene Terephthalate Glycol, known as PETG or PET-G, is Originate 3d’s go-to plastic for many applications. It is a bit tricky to print but when dialed in the results are very good. Stronger and more heat resistant than PLA, PETG is a good choice where PLA will not do. It too is food safe with many plastic bottles being made from it.
Acrylonitrile Butadiene Styrene, or ABS, was the standard plastic for 3d printing for years but has since been eclipsed by other choices. This is the plastic that Legos are made from. Temperamental to print, it is considered a challenge to obtain good prints using ABS. The reward are parts that can withstand higher temperatures than PETG. O3d printed exclusively ABS for years and knows exactly how to obtain good results. Originate 3d internally uses ABS in very limited applications where heat resistance is required.
ABS has an interesting feature in that it can be smoothed to a glass-like surface finish with the application of acetone vapors. This process can be temperamental but O3d has developed an expertise in this technique.
Thermoplastic Polyurethane, or TPU, is a flexible plastic. If one needs a gasket or cellphone case or other part that needs to be rubbery, this is the material to use. Like all flexibles it is time consuming as it requires very slow printing.
Nylon is a general name given to a class of plastics composed as polyamides. Prints made with Nylon are tough, semi flexible and wear well. Nylon prints require higher printing temperatures (twice that of PLA!) and are prone to warping. Unless your print requires the very highest level of durability and fatigue resistance PETG is often a better choice.
Many 3d printed plastics have some sort of additive to enhance the base plastic in some way. Carbon fiber is one of those additives and is added to most of the plastics listed above. Carbon Fiber prints are extremely stiff with almost no flex to them at all. Carbon Fiber enhanced plastics are very abrasive and require special hardened nozzles to print. The failure rate of carbon fiber prints is higher which means a higher cost to print per part.
PC is a relative newcomer on the 3d printing scene. Polycarbonate prints are semi flexible with a little bit of bend before breaking. It is naturally transparent and is a high strength material intended for serious engineering applications. It is also prone to warping and has a tendency to ooze when printing leading to lower quality prints.
There are all sorts of other materials available for printing. Glow in the dark? Yes. Brass? Yes. Wood fiber? Yes. While we may not have experience with exactly the one you are interested in do not hesitate to ask us about it. There is not a fiber out there that we cannot figure out how to print.
Resins for SLA
3d printer resin falls into four general categories: standard, engineering, biocompatible and castable. Each has its own strengths and weaknesses.
Standard resins are good for stiff, high resolution prints. The finish quality tends to be excellent with near injection molding finish quality. They are low cost and suitable for most applications. The downsides are that they tend to be brittle and have low impact resistance and tend to deform at relatively lower temperatures than other resins.
These resins are designed are more mechanically reliable and tough than standard resins. They do share the brittle nature of standard resins but have better impact resistance. They are generally unsuited for parts with thin walls. Temperature resistance is not particularly good on these resins.
Most resins are toxic and actually require protective gear to use when wet. Once cured they are safe, but if one has got an application that will be in regular contact with people one should use a biocompatible resin. Resins with both Class I and Class IIa biocompatibility are available.
When moldmaking with resins the technique often involves burning the print out of the mold made around it. Castable resins produce prints with excellent detail and do not leave ash behind when burnt out. The are well suited for jewellery and other intricate parts.
Most resins produce hard, inflexible prints. Prints made with flexible resins are rubber-like but have inferior performance to actual rubber parts. They are well suited for prototyping and adding ergonomic features to multimaterial assembiles such as stamps and grips. These do tend to degrade over time, especially if exposed to sunlight for significant lengths of time.
High temperature is less a category of resin and more of a characteristic. There are resins in each of the four previous categories that perform better in high temperature environments. If this is a feature you need we can accommodate it and select a resin to satisfy it.
Need More than Just 3d Printing? Let Us Know how We can Help.
Originate 3d is a full-service shop that can not only 3d print your designs but can also help you with product development and even manufacturing. If you would like to know more about our capabilities please contact us.