Filament Diagnostic Tool
Is My Filament Wet?
Wet filament is one of the most common causes of bad prints, and it is easy to miss. Pick your material, check off what you are seeing, and get a quick verdict plus a sensible drying starting point.
Drying recommendation
Starting points by material
Highlighted for your selected material once you run the check. These are general starting points, not exact settings: always verify against your dryer and the material spec sheet.
| Material | Temp | Time |
|---|---|---|
| PLA | 45-55 C | 4-6 h |
| PETG | 60-65 C | 4-6 h |
| TPU | 50-55 C | 4-6 h |
| ABS/ASA | 60-70 C | 4-6 h |
| Nylon (PA) | 70-80 C | 8-12 h |
| PC | 70-80 C | 6-8 h |
PETG, TPU, Nylon, and PC absorb moisture fastest. PLA absorbs more slowly but still does in humid conditions, so do not assume it is safe just because it printed fine last month.
This tool offers general guidance based on common, well-established drying ranges. It is not a substitute for your filament manufacturer's published specifications. When in doubt, follow the spec sheet and run a small test print.
How it works
How this tool works
The check starts from the material, because moisture behaves differently in each one. PLA absorbs slowly and shows it as a rough, dull surface and weak layer bonds. PETG, TPU and nylon pull water out of the air within hours and announce it with popping, hissing and stringing. ABS, ASA and polycarbonate sit in between. Once you pick the material, the symptom list is filtered to the ones that moisture actually causes, so a warped corner or a blocked nozzle is not blamed on wet filament when the real cause is elsewhere.
The verdict weighs the symptoms you ticked against how hygroscopic the material is. Two strong signs on nylon is a near-certain wet spool; the same two signs on PLA might just be a print temperature problem, and the tool says so. The drying recommendation then comes from published manufacturer ranges for that material, not from one dryer brand's presets, with a conservative starting temperature so a low-cost dryer cannot soften the spool.
Reading the result
How to read your result
Treat the verdict as a probability, not a diagnosis. A likely-wet result means drying is the cheapest first experiment, and if the symptom vanishes you have your answer. A probably-not-wet result is just as useful: it sends you back to temperature, retraction or bed adhesion instead of burning eight hours in a dryer for nothing.
The drying temperature and time are a starting point. Run the full time, print a short test with the same settings as the bad print, and compare. If it is only partly better, add a few hours rather than raising the temperature, because heat above the material's glass transition deforms the spool and fuses the windings.
FAQ
Questions people ask
Can I dry filament in a kitchen oven?+
You can, but most home ovens overshoot low temperatures by 10 to 20 degrees and cycle wildly, which is enough to warp a PLA spool. Use an oven thermometer, set it to the lowest setting, and prefer a purpose-built dryer or a food dehydrator for anything under 60 C.
How do I know the filament is dry enough?+
Print the same small test you used when it was bad. No popping, a smooth surface and clean bridging mean it is dry. A cheap hygrometer in the storage box, reading under 20 percent relative humidity, tells you it stays that way.
Does drying fix filament that has been wet for months?+
Usually for PLA and PETG. Nylon and TPU that have been damp for a long time can suffer hydrolysis, a chemical change drying cannot undo, and stay brittle. Dry it once, test, and retire the spool if it still snaps.
Why does the tool ask for the material first?+
Because the same symptom means different things. Stringing on nylon almost always means moisture; stringing on PLA is usually retraction or temperature. Filtering by material keeps the verdict honest.