Dry filament with moving warm air at the temperature on its data sheet, for 6 to 12 hours, and do not round the temperature up. PLA dries at 45 to 55 °C and starts to deform under load at 54 to 60 °C, so the safe window is about the width of a cheap oven’s thermostat error. A purpose-built dryer is the right tool. A kitchen oven is the riskiest one.
Temperatures and times
The first column is the range across the maker data sheets in our drying chart. The next two are what Prusa and Bambu Lab publish in their own drying guides. Use the figure for your brand where you have it.
| Material | Data sheet range | Prusa (Prusament) | Bambu Lab, forced-air oven |
|---|---|---|---|
| PLA | 50 to 55 °C, 6 to 8 h | 45 °C, 6 h | 50 °C, 8 h |
| PETG | 60 to 65 °C, 8 h | 55 °C, 6 h | 60 to 65 °C, 8 h |
| ABS | 75 to 80 °C, 7 to 8 h | not listed | 75 to 85 °C, 8 h |
| ASA | 75 to 80 °C, 7 to 8 h | 80 °C, 4 h | 75 to 85 °C, 8 h |
| TPU 95A | 70 °C, 7 to 8 h | 60 °C, 4 to 6 h | 70 °C, 8 h |
| Nylon (PA6 blends) | 70 to 95 °C, 7 to 12 h | not listed | 75 to 85 °C, 8 to 12 h |
| Carbon-fiber nylon | 80 to 100 °C, 8 to 12 h | 90 °C, 6 h (PA11 CF) | 75 to 85 °C, 8 to 12 h |
| PC | 75 to 80 °C, 6 to 8 h | 85 °C, 5 h (PC Blend) | 75 to 85 °C, 8 h |
| PVA | 45 to 80 °C, 4 to 12 h | not listed | 75 to 85 °C, 8 to 12 h |
Prusa’s filament drying guide runs cooler and shorter than everyone else, and warns about both directions: exceed the temperature and the filament softens and sticks together on the spool, exceed the time and you risk overdrying. Bambu Lab’s drying guide marks drying as required for TPU, PC, PVA and every nylon, and only recommended for PLA, PETG, ABS and ASA.
The wide ranges are real disagreements between brands, not rounding. eSUN’s ePA nylon page says dry it at 70 °C for more than 12 hours. Overture’s Easy Nylon listing says 95 °C for 7 hours. PVA runs from 45 °C on eSUN’s PVA page to 80 °C on Polymaker’s PolyDissolve S1 data sheet. For those materials a generic number is close to useless.
Why overshooting ruins PLA
Put the drying temperature next to the heat deflection temperature (HDT) from the same data sheet. HDT is the point where a test bar bends under a fixed load.
| PLA data sheet | Drying temperature | HDT at 0.45 MPa | HDT at 1.8 MPa | Margin to the lower HDT |
|---|---|---|---|---|
| Bambu Lab PLA Basic | 50 °C | 57 °C | 54 °C | 4 °C |
| Polymaker PolyLite PLA | 55 °C | 60 °C | 58 °C | 3 °C |
| Prusament PLA | 45 °C (Prusa guide) | 55 °C | 55 °C | 10 °C |
A spool is not a test bar, but the filament on it sits in tight turns pressing on each other, which is a load. Three or four degrees is no margin at all if your heat source swings. That follows from the numbers, and it matches Prusa’s warning that home ovens are imprecise and that fluctuations which do not matter for food can damage low-temperature filament like PLA.
PETG has more room. Bambu’s PETG HF data sheet gives a drying temperature of 65 °C against an HDT of 69 °C at 0.45 MPa, which is still only 4 °C, but Prusa dries its PETG at 55 °C against 68 °C. If you are unsure, take the lower temperature and add time.
The spool can fail before the filament does. Prusa says its older black Prusament spools loosen above 45 °C unless you add a screw through the hub, the older grey ones are glued and hold to 90 °C, and the redesigned spools sold from October 2025 take 90 °C. Bambu quotes 80 to 90 °C as within its spool’s heat resistance. If your spool is some other brand, find out before you dry nylon on it.
Dryer, oven or printer bed
A filament dryer
The low-drama choice. Prusa’s one instruction is to check that the box actually reaches your filament’s drying temperature. Bambu states that its AMS 2 Pro tops out at 65 °C and its AMS HT at 85 °C, and lists ABS, ASA, PC, PVA and nylon as not compatible with AMS 2 Pro drying for that reason. It also notes the AMS 2 Pro may not fully dry TPU.
An oven
This is where the makers split. Bambu says flatly not to use a kitchen oven or a microwave: heat distribution is uneven and areas near the elements get hot enough to damage spool or filament. It recommends a forced-air convection oven with at least 250 x 250 x 90 mm inside for one spool, and the spool kept away from the heating elements. Prusa allows a home oven but attaches two conditions: use an external thermometer, and accept that many ovens cannot be set low enough, in which case a shorter time does not save you. I side with Bambu for PLA and PETG. The margin table above is the reason. A food dehydrator with the trays removed is Prusa’s other suggestion, again subject to checking its temperature range.
The printer’s heated bed
This works only on enclosed machines. Bambu says its open-frame printers (A1, A1 mini, P1P) cannot dry filament. On its enclosed printers the method is: spool on the bed under a cover such as the filament’s cardboard box, door and lid shut, 12 hours, and flip the spool halfway. The bed setpoints look alarming next to the table above, 60 to 70 °C for PLA and 75 to 85 °C for PETG. Those are bed temperatures, not air temperatures. Bambu’s own oven figure for the same PLA is 50 °C, so the 10 to 20 °C difference is best read as heat lost between the plate and the spool. Never carry a bed setpoint over to an oven or dryer.
Nylon and PC: store dry, do not rely on rescue
Bambu adds a warning worth knowing before you buy: polyamide left in open air for around three months absorbs so much water that a convection oven at 80 to 90 °C struggles to recover it. It also says PC can turn brittle after repeated heat and cool cycles. Both point the same way. Store these dry from day one, because drying is a rescue, and rescues do not always work. Prusa’s advice for the highly hygroscopic group (polyamide, polypropylene, PVA, BVOH) is to keep them in a dry box or dry before every print.
What a drying cycle costs
Bambu’s power consumption table gives the drying power of its units: 80 W for the AMS 2 Pro and 170 W for the AMS HT. A 12 hour PLA cycle in the AMS 2 Pro is 0.08 kW x 12 h = 0.96 kWh. At Ofgem’s price cap rate of 26.32 pence per kWh (October to December 2026) that is 25 pence. At the EIA’s US residential average of 18.34 cents per kWh (June 2026) it is 18 cents. Twelve hours in the AMS HT is 2.04 kWh, or 54 pence.
If the spool cost you $20, drying it costs about one percent of that. One failed print from wet filament costs more. For other dryers, read the wattage off the label and use the electricity cost calculator, keeping in mind that a label figure is a maximum and the real average will be lower.
How to tell it needs drying
Prusa’s list of symptoms: poor surface quality first, then stringing beyond what the material normally shows, weak layer adhesion, blobs, and in bad cases bubbling and visible steam or smoke at the nozzle. Nylon, PVA and TPU need drying far more often than PLA. On multi-tool printers such as the Prusa XL, idle toolheads sit at 70 °C by default and cook moisture out of the filament inside them, so Prusa recommends drying even PLA for that machine.
For anything that gives off fumes when heated, check the maker’s safety data sheet before you dry it indoors.
