How to Dry 3D Printer Filament (and When You Need To)
6 min read · Updated November 2026
Most 3D printing filaments absorb moisture from the air. Some, like nylon and TPU, can soak up enough in a day or two to cause problems. Wet filament prints badly, and the cause isn't always obvious, so it's worth knowing the signs and how to fix it.
Signs your filament is wet
- Popping, crackling or hissing from the nozzle as water turns to steam.
- More stringing than usual, even with tuned retraction.
- Rough, fuzzy or bubbly surfaces on walls.
- Weak, brittle parts with poor layer bonding.
- Inconsistent extrusion or small gaps in lines.
If a spool printed well when new and now shows these signs, moisture is the first thing to suspect.
Typical drying temperatures
These are common starting points, not exact rules. Always check your filament manufacturer's recommendation, because blends and brands differ.
| PLA | about 45–50°C, 4–6 h |
| PETG | about 60–65°C, 4–6 h |
| ABS / ASA | about 60–80°C, 4–6 h |
| TPU | about 45–55°C, 4–8 h |
| Nylon | about 70–80°C, 8–12 h |
Stay below the temperature where the material softens. PLA in particular starts to soften not far above its drying temperature, and a spool that softens can fuse into a solid lump.
How to dry it
A filament dryer
The easiest option. Dedicated dryers hold a steady temperature, and many let you print straight from the dryer so the filament stays dry during long prints.
A food dehydrator
Many hobbyists use one with the trays removed or cut out to fit a spool. Check its real temperature with a thermometer, since the dial is often approximate.
Avoid the kitchen oven
Ovens often overshoot their set temperature, especially at the low settings filament needs, and can melt a spool. Plastic fumes and food don't mix either.
Keep it dry
- Airtight storage: a sealed bin or vacuum bag with fresh desiccant.
- A cheap hygrometer in the box tells you when the desiccant needs drying or replacing.
- Put spools away after printing, especially nylon, TPU and PETG.
- Dry before long or important prints. A few hours of drying is cheaper than a failed 20-hour print.
Track what's on the shelf
A drying routine is easier when you know which spools you have, how much is left on each, and when you last used them. Spools that sit for months are the ones most likely to need drying.