How to dry filament and why it matters
Wet filament ruins prints: stringing, bubbles, weak layers. How to spot it and dry it properly.
2026-02-02 · 3DHub.ge
Most filament is hygroscopic — it absorbs moisture from the air. Wet filament produces weak, rough and ugly prints. It is one of the most common problems, and one of the most often overlooked.
How to tell your filament is wet
Signs:
- Popping or crackling sounds while printing — that is moisture flashing to steam in the nozzle.
- Heavy stringing even when retraction is tuned correctly.
- Tiny bubbles or a rough texture on the surface.
- Poor layer adhesion — the print falls apart easily.
Which materials absorb moisture fastest
Most sensitive: PA (nylon), TPU, PVA — within hours. Medium: PETG, ABS, ASA. Most resistant: PLA, though it too gets wet within a few weeks if stored in the open.
How to dry it
A filament dryer is the best option. You set temperature and time, and the spool dries evenly. Many models feed the printer directly from inside the dryer during printing.
An oven can work, but it is risky: temperature swings can deform the spool. Only use one that holds a low temperature accurately.
Rough temperatures and times:
| Material | Temperature | Time |
|---|---|---|
| PLA | 45–55°C | 4–6 h |
| PETG | 60–65°C | 4–6 h |
| ABS / ASA | 65–75°C | 4–6 h |
| TPU | 50–60°C | 6–8 h |
| PA (nylon) | 70–80°C | 8–12 h |
Storing it so it stays dry
After drying, keep filament in an airtight container with silica gel, or in a dry box. A spool left in the open will slowly absorb moisture again.
Frequently asked questions
Do I really need a filament dryer?
For PLA that you use quickly, no. But for PETG, ABS, TPU and especially nylon, a dryer is almost essential — it directly changes print quality.
Can I dry filament in a kitchen oven?
Carefully. Many ovens do not hold low temperatures accurately and the spool can be damaged. A dedicated dryer is safer and more reliable.
How long does dried filament stay dry?
It depends on storage. In an airtight box with silica gel — months. Left in the open in humid air — a few days to weeks.