PETG absorbs moisture from ambient air within hours of exposure. Drying it at 60-65°C for 4-6 hours restores print quality and prevents stringing, bubbling, and layer delamination.
Why PETG Absorbs Moisture
PETG is hygroscopic — its molecular structure attracts and bonds with water molecules from the surrounding air. Within 4-8 hours of exposure to ambient humidity (above 40% RH), PETG begins to degrade. After 24 hours, the effects are visible in your prints: stringing between features, surface bubbles, and reduced layer adhesion.
How to Dry PETG
- Set your filament dryer or oven to 60-65°C (140-150°F)
- Place the spool inside for 4-6 hours
- For severely wet filament, extend to 8 hours
- Store in a sealed bag with desiccant immediately after drying
Signs Your PETG Needs Drying
- Popping or sizzling sounds during extrusion
- Excessive stringing between print features
- Bubbles or voids in the surface finish
- Brittle layer adhesion — parts snap instead of flex
- Inconsistent extrusion with gaps
Prevention Tips
Vacuum-sealed packaging with desiccant — like the packaging we use for every Yiqiu3D spool — keeps filament dry during ocean transit and long-term storage. Once opened, store in a sealed bag or a filament dryer set to 45-55°C.
Print Settings After Drying
| Parameter | PETG Value |
|---|---|
| Nozzle temperature | 220-250°C |
| Bed temperature | 70-80°C |
| Print speed | 30-60mm/s |
| Cooling fan | 30-50% |
Individual results depend on your printer, environment and application.