PLA vs PETG vs PCTG: which one for the part in front of you
TL;DR
- PLA for looks, speed and price. PLA+ when PLA cracks.
- PETG for outdoor, water and chemical exposure without an enclosure.
- PCTG when PETG breaks: 8× the impact strength and 101 °C HDT, at a 100 °C bed.
The numbers, same instruments, same day
All four are extruded on the same lines and tested on the same tensile and Charpy instruments, so the comparison is fair.
| Material | Tensile (MPa) | Impact (kJ/m²) | HDT (°C) | Bed (°C) | Enclosure |
|---|---|---|---|---|---|
| PLA | 40 ± 6 | 5 ± 3 | 55 ± 5 | 50–65 | No |
| PLA+ | 40 ± 6 | 5 ± 3 | 55 ± 5 | 50–65 | No |
| PETG | 48 ± 10 | 3 ± 1 | 70 ± 5 | 60–70 | No |
| PCTG | 50 ± 3 | 25 ± 5 | 101 ± 2 | 100–110 | Optional |
How to decide
Ask three questions. Will the part sit in a hot car or near a heater? Then PETG is the floor and PCTG is safer. Will it get dropped or flexed? PLA+ for light duty, PCTG for anything that must not crack. Does it need to look perfect? PLA in Matte or Silk wins on finish.
Price matters at print-farm scale: PLA costs least per kg, PETG a little more, PCTG about 50 % more. Only pay for PCTG where the part earns it.
