Between four hours and a full day, depending entirely on the material:
| Material | Temperature | Hours |
|---|---|---|
| PLA and PLA blends | 45 °C | 4–6 |
| TPU 95A / 98A | 60 °C | 4–6 |
| PETG, ABS, ASA, HIPS | 65 °C | 4–6 |
| PETG-CF, PET | 65–70 °C | 6–8 |
| PVA, BVOH | 45–50 °C | 6–12 |
| Polycarbonate | 90 °C | 6–12 |
| Nylons and their filled grades | 80 °C | 8–12 |
| PPA | 100 °C | 8–16 |
| ULTEM 9085, PEEK | 120 °C | 8–24 |
Longer is safe, hotter is not
The hours in that table are minimums for a moderately damp spool. Running a cycle twice as long does no harm; running it above the material's softening point welds the coil to itself and destroys the reel.
That asymmetry is the whole reason the temperature column matters more than the hours column. If you are unsure, leave it longer at the correct temperature rather than raising the heat to save time.
How to know when it is actually done
Weigh the spool before and after. Water leaving the filament is mass leaving the spool, and on a genuinely wet reel that is a readable difference on a kitchen scale.
Two consecutive weighings with no change means the cycle has finished, whatever the schedule said. That test also catches the opposite case — a spool that was never wet, where you have spent six hours and learned something useful.
Why the schedules vary so much
The polymer's affinity for water and its softening point pull in opposite directions. Nylon holds a lot of water and softens high, so it gets a long hot cycle. PLA holds little and softens low, so it gets a short cool one. PEEK sits at the far end of both scales.
The filled grades add time rather than temperature: fibre and particle interfaces trap water that the base polymer would have given up sooner.
What it costs to run
Almost nothing per cycle — a six-hour run in a 50 W dryer costs about 5 cents. Leaving that dryer on permanently as a dry box is a different matter, at 438 kWh and $76.65 a year.
Cost a cycle for your own unit by entering its wattage and the hours above in the print cost calculator. Method and equipment are in the drying guide; per-material schedules sit on the materials index.