How to dry and store filaments for 3D printing

The worst enemy of any filament is humidity.

To use a Filament for a long time, however, you will have to deal with environmental humidity.

However, we will explain how to best preserve your coils and how to recover coils that have already been exposed to humidity.

How to recognize a wet filament?

The signs that a filament is wet, in order of severity, from least to most serious, are:

Excessive fragility of the Filament;

Bubbles and crackling noises at the exit of the hot nozzle;

Rough print surface;

Difficulty in extrusion;

Fragility of the Press.

Surface and deep humidity

If the humidity is only SUPERFICIAL it will only cause aesthetic damage to your prints, which will appear less smooth.

If, however, the humidity has penetrated DEEPER, into the heart of the Filament, in this case it could cause serious damage to your prints and to the chemistry of the Filament itself, compromising the final characteristics and the robustness of the object itself.

The cube on the left was printed with filament stored inside Creality's Dry-Box, the one on the right was printed with the same filament, which did not undergo the drying treatment.

Drying Temperature and Times

Each material has specific drying times, but it's also important to consider that each material, regardless of the brand you're using, will require different drying temperatures and times.

So which one to choose?

To avoid going crazy, a general rule of thumb is to consider the Glass Transition Temperature (Tg). This parameter can be found in the filament datasheets; if it's not there, you can request it directly from the manufacturer. Another way to calculate it is to look at the melting point of the material and subtract 30%.

Here are some methods to recover the coils in case of humidity

If your spool has been open for a long time, it's always a good idea to dry the filament. However, we at 3Digital always recommend drying the filament before each print for best results.

There are various methods, from the most home-based to the most professional, and various factors must be considered, including the energy consumption of the device used.

Be careful ⚠ of some materials

Indeed, some materials are particularly hygroscopic, meaning they are susceptible to wear and tear caused by humidity. For example, polyamide, nylon, PEEK, and PET. For these materials, even just a few hours of exposure to humidity can cause printing problems. For this reason, they should be printed in a heated chamber or stored in special dryers.

Filament Dryer

Designed for this purpose, it's definitely the best way to preserve or recover your reels. They usually allow you to set them based on the material you're drying. They can operate independently. Some are designed to dry the reel next to the printer, saving you time.

Furthermore, being designed for this, unlike some home methods, they consume little.

Examples are: the Creality Filament Dry Box.

The Creality Filament Dry Box pictured is a spool dryer specifically designed to protect your filament from the elements.

Food dehydrator

These devices are designed for drying fruit and vegetables. But they're also quite suitable for drying rolls.

The only drawback is the uneven heat distribution. Heat is typically distributed from bottom to top, as the tops dry food in layers on trays stacked one above the other.

Home oven

This is certainly the cheapest method for drying coils. But it's also the most imprecise, as the oven can reach high temperatures, so before inserting the coil, check the temperature with a thermometer to make sure it's not too high, otherwise you risk melting the filament. It can also be dangerous because some materials could release toxic substances into your oven, which will then make it impossible to cook your food if it's contaminated.

Store filaments correctly

We at 3Digital recommend that you conserve and preserve your filaments.

After drying, you can store them in the dehydrator itself or in airtight plastic bags. Add a moisture absorber like silica gel to the bag.