3D printing filament absorbs moisture from the air at varying rates depending on the specific type of filament. When enough moisture has been absorbed, print quality with that specific roll of filament begins to decline. Quality can be restored by drying your filament.

By elevating the plastic to a specific temperature (usually just above Tg¹⁾), the water can escape the network of plastic molecules and enter the far drier (due to elevated temperature) air.

The higher the temperature used, the faster the drying occurs, but the greater the risk of melting or annealing your filament. Cold temperatures (below Tg²⁾) can be used with limited degrees of success, but should not be expected to work well.

Please see the oven page for more information on drying equipment whether it be lab oven, filament drier, or anything in between.

Information on viable filament-specific drying temperatures can be found on their own filament page.

If you are working with especially hygroscopic³⁾ filaments, plan to immediately store your plastic in a drybox.