PLA, ABS & PETG
3D Printing Materials
The three most widely used FDM printing materials — each with distinct strengths, temperature limits, and ideal applications. Understanding the difference helps you get the right part from the first print.
Side-by-Side Comparison
| Property | PLA | ABS | PETG |
|---|---|---|---|
| Tensile Strength | 50–65 MPa | 40–55 MPa | 50–60 MPa |
| Heat Deflection Temp (HDT) | 55–60°C | 90–100°C | 70–80°C |
| Print Difficulty | Easy — beginner-friendly | Moderate — requires enclosure | Easy to moderate |
| Warping Tendency | Low | High (enclosed printer required) | Low to moderate |
| Impact Resistance | Moderate | High | High |
| Finish Quality | Good — sands well | Very good — acetone-smoothable | Good — slight surface sheen |
| UV Resistance | Poor — yellows outdoors | Moderate — degrades over time | Moderate |
| Moisture Resistance | Low — absorbs moisture | Moderate | Good |
| Translucency Option | Yes (limited colors) | No | Yes — excellent clarity available |
| Relative Cost | Low | Low–moderate | Moderate |
| Biodegradability | Bioplastic base — compostable | Petroleum-based | Petroleum-based — recyclable |
PLA — Best for Prototypes & Display Models
Properties
PLA (Polylactic Acid) is a bioplastic derived from renewable resources like cornstarch. It is the easiest material to print with high dimensional accuracy, making it the default choice for prototypes, display models, and architectural models. It sands, primes, and paints exceptionally well.
- Tensile strength: 50–65 MPa
- Elongation at break: 3–6%
- Heat deflection: 55–60°C (will warp in a hot car)
- Available in 20+ colors including white, black, gray, wood-fill, metal-fill
Best Applications
- Architectural and scale models
- Product prototypes and concept models
- Display pieces and presentation models
- Educational models and teaching aids
- Trade show props and exhibit elements
- Figurines and decorative objects
- Non-functional mockups and visual samples
ABS — Best for Functional Parts & Heat Applications
Properties
ABS (Acrylonitrile Butadiene Styrene) is the classic engineering plastic — the same material used in LEGO bricks, automotive interior panels, and consumer electronics housings. It handles heat and impact significantly better than PLA and can be chemically smoothed with acetone vapor for an excellent surface finish.
- Tensile strength: 40–55 MPa
- Heat deflection: 90–100°C
- Impact resistance: significantly higher than PLA
- Acetone vapor smoothing: eliminates layer lines completely
- Available in standard colors; black and white most common
Best Applications
- Functional enclosures and housings
- Automotive interior mockups and brackets
- Parts that will be used near heat sources
- Consumer product prototypes requiring impact resistance
- Tooling aids and assembly jigs
- Costume and cosplay armor (durable, sandable)
- Parts requiring a chemically smooth finish
PETG — Best for Functional, Chemical-Resistant, or Translucent Parts
Properties
PETG (Polyethylene Terephthalate Glycol) bridges the gap between PLA and ABS — easier to print than ABS, stronger and more heat-resistant than PLA, with excellent chemical resistance and available in clear/translucent variants. It’s also one of the most food-safe FDM options when printed on clean equipment with food-safe filament.
- Tensile strength: 50–60 MPa
- Heat deflection: 70–80°C
- Chemical resistance: good against most common chemicals
- Moisture resistance: excellent
- Clear/translucent options: best in class for FDM
Best Applications
- Clear panels, light diffusers, and transparent parts
- Containers and enclosures requiring moisture resistance
- Food-safe containers and kitchen tools (food-grade PETG required)
- Outdoor parts requiring weather resistance
- Architectural glazing simulation in scale models
- Medical device housings and lab equipment
- Parts requiring both strength and ductility
Frequently Asked Questions
It depends on which property you mean by “strongest.” In tensile strength (resistance to pulling apart), PLA and PETG are similar at 50–65 MPa, with ABS slightly lower at 40–55 MPa. In impact resistance (resistance to sudden force), ABS leads significantly — it’s much more resistant to cracking from drops or impacts. PETG has the best combination of tensile strength and impact resistance with the easiest print characteristics. For most functional applications where toughness matters, PETG or ABS is the better choice than PLA, despite PLA’s good tensile numbers on paper.
PLA has a heat deflection temperature of approximately 55–60°C. In practical terms, this means PLA parts left in a hot car on a summer day in Houston (interior temperatures regularly exceed 60°C) will warp or deform. PLA is not suitable for applications near heat sources, outdoor environments with direct sun exposure, or any part that will experience temperatures above 50°C in use. For those applications, choose ABS (90–100°C HDT) or PETG (70–80°C HDT) at minimum. Engineering materials like PC, ASA, or Nylon handle even higher temperatures.
Yes — all three materials accept paint well with proper surface preparation. The standard process is: sand progressively from 120 grit to 400 grit, clean with isopropyl alcohol, apply a plastic-compatible primer (rattle can or spray), then apply your topcoat color. PLA accepts this process particularly well and is the easiest to sand smoothly. ABS can be acetone-vapor smoothed before painting for an ultra-smooth base. PETG can be tricky because some paints don’t adhere well without a good primer coat — always use a plastic primer. We offer in-house sanding and painting services — ask about our finishing packages when you quote.
PETG can be food-safe in the right conditions, but FDM-printed PETG is not automatically food-safe. The issues are: layer lines create micro-gaps that harbor bacteria, most printers have brass nozzles that contain lead (not food-safe), and standard filaments may contain colorants or additives that aren’t food-grade. For food-safe applications, we print with food-grade certified PETG on a dedicated stainless-steel-nozzle printer with a clean filament path, and apply a food-safe resin coating to seal the surface. This is a specialty service — specify food-safe requirements when you quote and we’ll walk you through the options.
Choose SLA resin printing when surface quality is the priority — jewelry, miniatures, dental models, high-detail consumer product prototypes, and any application where you need near-injection-molded surface finish without extensive post-processing. FDM in PLA, ABS, or PETG wins on size (we can print much larger in FDM), cost (resin is typically more expensive per part), and for functional mechanical parts where layer adhesion anisotropy is less critical. If you need both fine detail and large size, we sometimes print the main body in FDM and detail components in SLA, then assemble — ask us about hybrid approaches for complex projects.