PETG Slicer Settings Guide
PETG (Polyethylene Terephthalate Glycol) sits between PLA and ABS in the difficulty ranking: stronger and more heat-resistant than PLA, easier to print than ABS. Its main challenge is stringing — PETG oozes at higher temperatures and requires more careful temperature and retraction tuning than PLA. Here are the exact settings that work.
PETG at a glance
PETG temperature by printer
| Brand | Model | Nozzle rec. | Bed rec. | Fan | Notes |
|---|---|---|---|---|---|
| Bambu Lab | P1P / P1S / X1C | 240°C | 70°C | 30% | Bambu profiles run warm for fast speeds. |
| Bambu Lab | A1 / A1 Mini | 240°C | 70°C | 30% | Textured PEI — no glue needed for PETG. |
| Prusa | MK4 | 240°C | 85°C | 50% | Prusa profiles use 85°C bed for PETG on smooth PEI. |
| Creality | K1 / K1 Max | 240°C | 70°C | 50% | — |
| Creality | Ender 3 V3 SE | 235°C | 75°C | 50% | — |
| Elegoo | Neptune 4 Pro | 240°C | 75°C | 50% | — |
| Anycubic | Kobra 3 | 240°C | 75°C | 40% | — |
| Voron | All | 240°C | 90°C | 50% | Voron runs high-bed temps for speed. |
Fixing PETG stringing
Stringing is PETG's most common problem. Work through these steps in order:
- Reduce nozzle temperature by 5°C. PETG stringing is primarily caused by too-high temperature. If you are at 250°C, try 245°C. Each 5°C reduction reduces ooze significantly.
- Lower retraction distance — but only slightly. PETG retraction distance should be 0.5–1 mm for direct drive, 2–4 mm for Bowden. Using too much retraction with PETG causes gaps and rough surfaces. If strings remain after temperature reduction, increase retraction by 0.2 mm at a time, not 1 mm jumps.
- Enable combing mode. Combing routes travel moves inside the printed walls so the nozzle never crosses open air. This eliminates most stringing without increasing retraction distance.
- Dry the filament. Moisture causes stringing that no amount of temperature or retraction tuning will fix. Dry PETG at 65°C for 4–6 hours and re-test.
- Increase travel speed. Faster travel moves give the oozing nozzle less time to deposit strings. Increase travel speed to 150–200 mm/s.
PETG bed adhesion
PETG has excellent adhesion on smooth PEI — sometimes too excellent. PETG can bond permanently to smooth PEI at high bed temperatures, making the part impossible to remove without damaging the bed.
- Smooth PEI: use glue stick or lower bed temperature
- Apply a thin layer of glue stick (Elmer's or similar) to smooth PEI before printing PETG. The glue acts as a release agent. Alternatively, lower bed temperature to 65–70°C — slightly less adhesion, but easier removal. Let the bed cool to 30°C before attempting to remove the part.
- Textured PEI: safe at 70–80°C without release agent
- Textured PEI surfaces (Bambu Lab, Prusa textured sheet) provide good adhesion for PETG without the risk of permanent bonding. No glue stick needed. Parts release cleanly when cooled.
- Glass bed: reliable but slower heating
- Borosilicate glass at 85°C with PETG adheres well and releases when cooled to room temperature. The downside is slower heat-up time. Apply a light coat of hairspray or glue stick for more consistent first layers.
PETG fan speed
PETG prints best with moderate fan speeds of 25–50%. Unlike PLA (which needs maximum cooling), PETG benefits from some heat to maintain good layer bonding. Too much fan causes layer delamination on PETG bridges and reduces inter-layer adhesion. Zero fan causes poor overhang quality.
A good general rule: use 25% fan for the first 3 layers (let them bond well), then 50% for the rest. On bridge spans, the slicer will automatically increase fan speed to 100% to cool the unsupported filament quickly.