How to store and dry filament

Filament absorbs moisture from the air. Dry storage prevents most of the trouble it causes.

Signs of wet filament

Popping or hissing at the nozzle, extra stringing, a rough surface and weak layers can all mean the filament has taken on moisture. PETG and TPU are affected sooner than PLA.

How to store it

Keep opened spools in a sealed bag or airtight box with desiccant. Keep them away from damp rooms such as an unheated garage. Unopened spools can stay in their original vacuum bag until you need them.

How to dry it

A filament dryer is the safest choice. As a starting point, dry PLA at 45 to 50 °C, TPU at 50 to 55 °C and PETG at 60 to 65 °C, for about 4 to 6 hours.

Household ovens can run hotter than their display says and may soften the spool, so check the temperature with a separate thermometer if you use one.