The question comes back with every useful print: should I stay with PLA, easy and precise, or switch to PETG for strength? The answer depends less on the material than on how the part is going to live.
At a glance
| Criterion | PLA | PETG |
|---|---|---|
| Ease of printing | Very easy | A bit trickier |
| Fine detail | Excellent | Good |
| Impact resistance | Brittle | Tougher and more flexible |
| Heat resistance | ~55 °C | ~75 °C |
| Moisture resistance | Average | Good |
| Stringing | Rare | Frequent |
When I reach for PLA
- Prototypes and decorative parts
- Figurines and objects with lots of fine detail
- Anything that stays indoors at room temperature
When I reach for PETG
- Brackets and mechanical parts under stress
- Objects exposed to heat, like a car parked in the sun
- Parts that live with moisture or outdoors
Starting settings for PETG
Nozzle: 235 °C
Bed: 75 °C
Part cooling fan: 30–50%
Speed: 40 mm/s for the first tests
Retraction: slightly shorter than for PLA
Tip: PETG sometimes sticks too well to a smooth bed. A thin layer of glue stick acts as a release agent here, not an adhesive, and keeps you from tearing off the bed's coating.
Before every print, I check that the spool hasn't absorbed moisture: a filament that crackles at the nozzle and leaves a rough surface needs a trip through the dryer.
- Filament dried
- Bed degreased
- Take a photo of the first successful part