How to dry Ultimaker materials?

Last updated on May 13, 2022 11:30

Why is it important to dry materials?

To have optimal print quality and mechanical properties, filaments should be as dry as possible. When filaments absorb moisture, print quality decreases, leading to inferior surface quality (e.g. stringing) and reduced mechanical properties of the 3D printed part.

How do I know if my filament is dry?

In extreme cases, you might even hear the filament "popping" when it is being extruded. However, at lower moisture levels, the impact on your printed part may be huge even though it is not immediately visible.

To have absolute certainty, you can measure the moisture level using a specialized apparatus, such as the Precisa Moisture Analyzer. The complete instructions can be found here.

If you do no have access to such instruments, the easiest way to ensure dry filament is a) to dry your filament according to the procedure below and b) store it properly.

How to dry my filament?

To dry filaments, elevated temperatures are required. Thus, storing the material with the silica desiccant in the packaging, or storing it in the Ultimaker Material Station, does not dry the material.

The best way: a dedicated drying apparatus

The best results are obtained with a dedicated apparatus that keeps the filament actively at a set temperature for a set period of time, while controlling humidity to a low level. At Ultimaker, our engineers use the PrintDry, but other products are on the market that do the same. Note that products such as the PolyBox only keep the material dry but do not actively dry it.

The next best: use your heated build plate

If you do not have access to dedicated drying equipment, it is also possible to dry your filament on the build plate of your Ultimaker 3D printer. Naturally, the humidity is not controlled, so it typically takes a bit longer and higher temperature to dry your filament; also the process is less controlled than in e.g. a PrintDry.

Drying temperature and time

It is important to dry your material at the optimal conditions for each polymer type. As a rule of thumb, materials should be dried below the glass transition temperature (Tg) of a material, to prevent crystallization or softening of the material, that could cause the filament to stick together. Also, the Ultimaker spools are made of a polypropylene copolymer that can soften around 70-80°C. When drying a complete spool, it is important to stay below this temperature.

The table below outlines the recommended drying temperature for each of the Ultimaker materials.

	Temperature PrintDry	Temperature build plate	Drying time (Print Dry)	Drying time (build plate)
PLA	40°C	50°C	4-8 hrs	4-8 hrs
Tough PLA	40°C	50°C	4-8 hrs	4-8 hrs
Nylon	40°C	50°C	10-20 hrs	10-20 hrs
TPU95A	40°C	50°C	10-20 hrs	10-20 hrs
Breakaway	40°C	50°C	4-8 hrs	4-8 hrs
PVA	50°C	60°C	10-20 hrs	10-20 hrs
PETG	65°C	70°C	4-8 hrs	10-20 hrs
CPE	65°C	70°C	4-8 hrs	10-20 hrs
CPE+	70°C	70°C	4-8 hrs	10-20 hrs
PC	70°C	70°C	4-8 hrs	10-20 hrs
ABS	70°C	70°C	4-8 hrs	10-20 hrs
PP	Not needed	Not needed

For most filaments, it is sufficient to dry the spool for 4-8 hours. Moisture sensitive filaments such as Nylon, PVA and TPU95A that contain a lot of moist should be dried overnight (for 10-20 hours). If drying on the build plate, for those filaments that require higher temperatures, also 10-20 hours is recommended.

How to keep my filament dry?

There are several ways to store the filament in such a way that it stays dry once properly dried.

In the Ultimaker Material Station, which controls humidity to a low level
With a desiccant in a sealed bag, following the recommendations for PVA
In a third party dry box such as the PolyBox

Note: For more information for optimal drying conditions of third party materials, please take a look at the technical data sheets or printing guidelines, e.g. on the Ultimaker Marketplace.