Guide
How to Choose a 3D Printing Material: PLA, PETG, Nylon, Resin and Metal
By the Triiidiii editors · Updated
The material you choose decides how strong, flexible, detailed and heat-resistant your part will be, and it is usually the biggest single factor in the price. It also limits which process can make the part: you can't get SLS-printed PLA or FDM-printed titanium. So the useful question is not “which material is best?” but “what does this part have to do?”
Start with what the part has to do
- Only has to look right (a display model, a figure, a form check): PLA by FDM, or a standard resin by SLA if fine detail matters.
- Has to work (clips, brackets, housings, gears): PETG or ASA by FDM for simple shapes, nylon by SLS or MJF for complex or load-bearing parts.
- Has to bend: TPU, or a flexible resin for small, detailed parts.
- Gets hot or lives outdoors: ASA, nylon, or an engineering resin rated for heat. Avoid PLA.
- Has to be metal: stainless steel, aluminum or titanium by metal printing, or a precious metal cast from a printed pattern for jewelry.
The common materials at a glance
| Material | Process | Good for | Watch out for |
|---|---|---|---|
| PLA | FDM | Display models, early prototypes, low-cost parts | Softens at fairly low temperatures; brittle under impact |
| PETG | FDM | Tougher everyday parts, enclosures, brackets | Surface is a little glossy; fine detail is limited |
| ABS / ASA | FDM | Heat-tolerant parts; ASA for outdoor use | Can warp on large flat parts |
| TPU | FDM, SLS, MJF | Flexible parts: seals, grips, bumpers | Hardness varies by grade, so check the Shore rating |
| Nylon (PA12, PA11) | SLS, MJF | Strong functional parts, snap fits, small batches | Grainy surface unless smoothed or dyed |
| Standard resin | SLA, DLP | Fine detail, smooth surfaces, visual prototypes | Can be brittle; some resins yellow in sunlight |
| Engineering resin | SLA, DLP | Tough, heat-resistant or flexible prototypes | Costs more than standard resin |
| Stainless steel, aluminum, titanium | SLM / DMLS, binder jetting | Metal functional parts and complex shapes | Much more expensive; strict design rules |
| Silver, gold, brass, bronze | Lost-wax casting from a printed pattern | Jewelry and small decorative pieces | Priced partly by metal weight |
A general guide, not a specification. Each service names its own grades and publishes data sheets: check the material page of the service you order from before you rely on a property.
Plastics for FDM: PLA, PETG, ABS, ASA, TPU
FDM (fused deposition modeling) melts a plastic filament and lays it down line by line. It is usually the cheapest option and the materials are familiar from desktop printers. PLA is easy to print and fine for models, but it softens in a hot car. PETG is tougher and handles moisture and moderate heat better. ABS and ASA take more heat, and ASA also resists UV light, which is why it is used outdoors. TPU is rubbery and comes in different hardnesses.
Some services also offer filled filaments, such as carbon-fiber nylon, and high-temperature plastics such as PEEK or Ultem. They are stiffer or more heat-resistant, and cost considerably more.
Nylon for SLS and MJF
Powder-bed processes (SLS and HP's Multi Jet Fusion) fuse nylon powder layer by layer. PA12 and PA11 nylon are the workhorses: strong, slightly flexible, and good for snap fits and moving parts. Because the loose powder supports the part, complex shapes print without support structures. The raw surface is matte and slightly grainy; dyeing, smoothing and painting are common options. Glass- or carbon-filled grades are stiffer.
Resins for SLA and DLP
SLA and DLP cure liquid resin with light, which gives the finest detail and the smoothest surfaces of the common processes. Standard resins suit visual models and fit checks but can be brittle. Engineering resins are formulated to be tough, heat-resistant, flexible, clear or castable. Resin parts can change over time in strong sunlight, so ask about UV stability for outdoor parts.
Metals
Metal printing (SLM or DMLS, sometimes binder jetting) builds dense parts from metal powder in stainless steel, aluminum, titanium and other alloys. It is used for functional parts with shapes that would be hard to machine. Expect a much higher price, longer lead times and stricter design rules: minimum wall thickness, support removal and powder removal all matter.
For jewelry, many services print a wax or resin pattern and cast it in silver, gold, brass or bronze. That gives you a precious-metal part with printed detail.
Still undecided?
- Pick the process first with our FDM vs SLA vs SLS guide.
- Upload the same file to two or three services and compare the instant quotes for your shortlist of materials.
- For an important part, order one piece in your top two materials before you order a batch.
See which materials each service lists in our comparison of six services.