PLA vs PETG vs ABS: Which 3D Printing Filament Should You Use?
In short, Choose PLA for decorative models, prototypes, and sharp visual details. Choose PETG for functional indoor/outdoor brackets, tool holders, and water resistance without needing an enclosed printer. Choose ABS (or ASA) if the part will live inside a hot car (above 60°C/140°F) or requires acetone vapor smoothing.
1. Heat Deflection Temperature (HDT)
The number one reason 3D prints fail in the real world is temperature creep. PLA begins softening at just 55°C to 60°C (130°F). If you print a phone mount or sunglasses clip out of PLA and leave it inside a parked car in July, it will droop into an unusable melted blob within two hours.
PETG resists heat up to 75°C to 80°C, making it safe for indirect outdoor exposure. ABS resists heat all the way up to 100°C (212°F), meaning it survives direct engine bay proximity and hot vehicle interiors without deformation.
2. Print Ease and Warping Behavior
PLA is the king of ease: zero bed warping, sticks to standard PEI at 60°C, and requires no heated enclosure.
PETG prints easily on an open-frame printer but has high surface tension. It can stick too aggressively to bare smooth PEI or glass, taking chunks of glass coating with it unless you use a glue stick or textured sheet.
ABS has severe thermal shrinkage (~1.5% volumetric contraction upon cooling). On an open printer, cold ambient drafts will cause layer delamination and cause corners to peel off the bed with tremendous force. ABS requires a heated chamber or enclosed printer.
Head-to-Head Specification Table
| Property | PLA | PETG | ABS |
|---|---|---|---|
| Density (g/cm³) | 1.24 | 1.27 | 1.04 (Lightest) |
| Heat Resistance (HDT) | 55°C (Low) | 75°C (Medium) | 100°C (High) |
| Impact Resistance | Brittle (Snaps) | Ductile (Bends) | Tough / Absorbing |
| UV Weatherability | Degrades over years | Excellent | Yellows (Use ASA instead) |
| Enclosure Required? | No | No | Yes |
| Odor / VOC Emissions | Sweet / Harmless | Low odor | Styrene fumes (Filter needed) |