The two primary technologies used for desktop 3D printing are fused deposition modeling (FDM) and stereolithography (SLA). For those new to 3D printing, FDM technology feeds melted plastic filament through a nozzle that traces out a design one layer at a time from the bottom up. SLA technology, builds the layers of a print by curing resin with specific wavelengths of light. These two types of 3D printers use different materials for printing. FDM machines use filament and SLA machines use resin.
If you are working with an FDM printer, you will use one of two sizes of filament: 1.75mm or 2.85mm. It’s very important to check which diameter of filament your 3D printer uses because using the wrong size will cause failed prints and can even damage your machine.
Every FDM printer has slightly different characteristics so keep in mind the temperature, speed, and functional ranges of your printer when choosing filament. Resin is the input material for SLA 3D printers. It is a viscous liquid that comes in bottles,
whereas FDM filament is solid and comes in rolls. With open print settings
enabled on an SLA printer, most resins are compatible so temperature and speed
of your printer are not an issue. To decide which type of resin you want to
use, you should think about the purpose of the model and what
properties you want it to have.
This guide breaks up printing materials into four categories based on function and purpose so you can decide which is needed for your project.
General Purpose: If you’re a 3D designer who wants to print detailed models or a hobbyist looking to get started with 3D printing.
Functional: If you’re looking to produce functional prototypes that simulate a material you want to create your end product in.
Aesthetic: If you’re a 3D designer or hobbyist looking to play around with different effects that serve a more aesthetic than functional purpose.
Application Specific: If you’re a dentist, jewelry maker, engineer, or artist, looking for specialty materials that are used for industry specific purposes including dentistry, casting, electronics, and ceramics.
Whether you’re new to 3D printing or are an experienced maker looking to experiment with new material options, this guide will help you explore all the different material possibilities your printer can work with.
PLA (Polylactic Acid)
PLA is made from bio materials like cornstarch, sugar cane and tapioca root which makes it biodegradable. When heated, it gives off a sweet aroma that smells similar to syrup. Unlike ABS, it doesn’t give off toxic fumes so an enclosure isn’t necessary. In general, PLA is less temperamental and requires a lower temperature to print than ABS and does not need a heated build plate. The layer bonding is very strong with PLA , however, the material itself is brittle and will break or crack if you drop it. If you need something for engineering purposes then a tougher material might be more appropriate.
HIPS (High Impact Polystyrene)
HIPS is primarily used as support material for ABS and works well when used with a dual extrusion FDM printer. HIPS is a great support material because it easily dissolves in Limonene. This makes removing the supports during post processing easy, leaving you with a clean print. This is ideal material for printing designs that have overhangs or complicated parts. It can also be used like PLA on its own as a general purpose material.
PET (Polyethylene terephthalate)
PET is both flexible and sturdy, making it a great material for functional, engineering quality products. It’s chemically resistant and does not absorb water like many other materials. PET has a similar price range to PLA and ABS and is mechanically similar to ABS though it can be printed without a heated build plate and is extruded between 220-250 C. The layer bonding is very strong which allows it to be used in mechanical parts, drones, and wearable technology.
Standard resin is great if you are creating a prototype of a product that won’t undergo intense stress from functional use. It comes in a variety of colours and will leave your prints with a smooth surface finish. Since SLA printers are capable of producing finer details in parts, this resin is commonly used by engineers or designers who are prioritizing the look of the print rather than function.
ABS has a higher melting point than other filaments and needs a heated build platform to prevent warping. It is also slightly stronger than PLA so if you are looking for strength in a print, ABS might be the way to go. Its strength and durability will give your print a longer service life, but it has poor UV resistance which is not ideal if you plan on using your print outdoors. ABS is also known to give off harmful fumes during printing so an enclosure and ventilation are recommended.
This resin was specially made for durability and impact strength. Much like ABS plastic, tough resin is best used for functional, engineering related parts. Tough resin can withstand high amounts of stress and elongation before failure.
Carbon Fiber PLA is well-liked because of its high strength and durability. Proto-Pasta’s carbon fiber filament combines PLA with 15% carbon fiber strands by volume. This filament has a tendency to be brittle so be extra careful when feeding it through your printer. It’s strength is perfect for printing drones, remote control cars, propellers, and frames. The added carbons fibers does mean the filament works best with larger nozzle sizes like 0.4mm and up.
Nylon is a low friction material that boasts very high strength and durability. The material is flexible especially for thinner models. Its layer bonding is the strongest of all commonly used FDM filaments. Some types of nylon are used in medical devices, toys, and FDA approved products. For proper storage, it should be kept in a non-humid environment.
Flexible Filament (TPE and TPU)
Flexible filaments are typically made of polyurethane or polyethylene. They can be challenging to print because the filament tends to buckle in the extruder which can cause print failures. For best results, we recommend printing with a direct drive extruder and printing at higher extrusion temperatures. Slowing down print speeds will also help to avoid failed prints. For more detailed instructions on how to successfully print with flexible filament, check out our blog on Top 5 Tips for Best Results with Flexible Filament .
SLA also has flexible resin that allows you to print bendable and functional parts. It is especially useful for ergonomic prototypes like handles and grips. Although FDM printers sometimes require special nozzles for printing flexible filament, resin printers do not require any special add-ons for printing with flexible resin.
Formlabs just came out with a material which has a has a heat deflection temperature of 289 C at .45 MPa which is the highest temperature resistance on the market at that pressure. This makes it the perfect material for applications that expose your print to high temperatures like mold prototyping, environmental testing, and fluidics.
Durable resin is a low friction and high impact strength resin that simulates polypropylene. This material is great for consumer product prototypes and parts that will undergo wear like ball joints and bearings.
Filament like Woodfill and Laywood are made from a combination of plastic infused with wood fiber and polymer binders that allow it to be extruded with similar settings to PLA. This allows you to emulate a wood like appearance and feel. Because wood filaments are PLA based, they don’t require a heated bed to print. You can oftentimes change the color of the filament by changing the temperature. This can be used to create a neat layered effect much like real wood. For more details on post processing wood prints, check out our blog on 3D printing wood finishing techniques.
Thermo Temperature Changing PLA
This filament will change colors when exposed to higher temperatures. Different varieties will offer different colours as well - some will change from blue to green and others from grey to white, and the list goes on. The filament is PLA based and doesn’t require a heated bed. There is another PLA based filament that changes colors based on light exposure. Thermochromic PLA has a number of neat applications from cell phone cases to consumer products.
Metal Filled PLA
Metal filled filaments are made by combining PLA with metal powder. The four most popular metal composites are bronze, copper, steel, and iron. The metal powder makes it around four times heavier than standard PLA. Although it looks and feels like metal when printed, it does require some post processing to capture the full effect. Before post-processing, Bronze PLA typically has a dull, rough appearance and the goal is to bring bronze particle to the surface of the object. Check out our blog on post processing metal filaments for more details on how to sand and smooth metal prints. To learn more about optimal settings for metal composites, check out our blog post on how to get started.
Conductive PLA offers a number of options for basic, low voltage applications. Examples of applications include LEDs and Arduino projects. Conductive PLA as a general rule will work with anything that can be run through a 1000 ohm resistor. Although the material is sturdy, it shouldn’t be used for heavy mechanical applications. Conductive PLA can adhere to standard PLA which is very helpful if you want to print circuits on top of a regular PLA print.
Castable resin is used for making investment cast molds at high detail. Design your part in CAD, 3D print it in a castable material, and use that printed part in investment casting as you would a wax model. Castable resins burn out cleanly with minimal ash or residue left behind to clean up, which makes it ideal for parts like jewelry, miniatures, or small mechanical components.
Ceramic resins are a good choice for artists or individuals with very high heat applications. The print process is similar to other resins, however you have the option to fire and glaze it afterwards.
There are a number of different biocompatible resins on the market with different certifications. These materials can be used to create surgical guides, unique to patients for increased accuracy during surgery and improved clinical outcomes.