Drying filament: How to keep your filament supple

Printing errors can quickly ensure that not much remains of an actually beautiful work. Printing errors are particularly frequent in connection with damp filament. Therefore, we will show you below how you can dry your filament and thus prevent printing errors.

The most important in a nutshell

  • Filament should always be stored dry, as moist materials can lead to printing errors
  • Damp filament causes, among other things, unevenness on the surface, hairy filaments in the print or clogged extrusion nozzles
  • Damp filament does not have to be disposed of immediately, but can be dried in many cases.
  • If you want to dry filament, you can use several options, such as the oven, special filament dryers or automatic dehydrators.

Why should I dry filament?

The filaments and printing materials are usually materials with a highly hygroscopic property. That sounds quite sympathetic. However, this mainly says that the materials very easily absorb the moisture of the environment. In the case of filament, this can have negative consequences and lead to massive printing errors.

In general, it is therefore important to store the filament correctly already and thus prevent moisture. However, if the moisture has already been absorbed, there are several ways to dry the filament. In the best case, you can prevent the materials from becoming completely unusable.

Why is moisture not good for filament?

The moisture can cause tremendous damage to the 3D printing filaments. The reason is that plastic polymers are built up in molecular chains. Moisture breaks the chains and can render the entire material unusable. Damp filament often brings with it a whole host of problems. This includes, for example, uneven surface texture resulting from impaired uniformity of extrusion. In addition, wet filament can even cause the extrusion die to clog completely.

Another problem with wet filaments is filament formation during printing. These small threads usually can't be corrected by post-processing, nor can you avoid them by adjusting the print parameters.

Detect wet filament

You can tell if your filament is wet by looking at several criteria. For example, if you can hear crackling, popping or slightly popping noises in the nozzle, this is pretty much an indication of wet filament. In addition to this, however, reduced part strength may indicate that the filament used may have been too wet. We have listed the typical characteristics of moist printing materials here:

  • Crackling, popping or slightly popping noises in the extrusion die
  • Reduced strength of the parts
  • Layer adhesion noticeably reduced
  • Extrusion lines are not uniform
  • Occurrence of wetness and increased spotting
  • White smoke emission during extrusion

Drying filament: These are your options

From conventional to modern. If you want to dry your filament, you have several options to choose from. We will introduce you to them in the following:

1. the initial cheapest option: use your oven

An inexpensive and at the same time widely used method, is to heat the filaments in the oven. Depending on the material, you must observe different temperatures and times. In addition, it is advisable to put the material in the preheated oven. Many ovens heat up strongly after being switched on, which in the worst case can lead to damage to the filament.

FilamentTemperatureDuration in oven
PLA40-45 degrees Celsiusmin. 4-6 hours
ABS80 degree Celsiusmin. 4-6 hours
PETG60 degrees Celsiusmin. 2-4 hours
PA/Nylon80 degree Celsiusmin. 4-6 hours
ASA70 degrees Celsiusmin. 3-5 hours
HIPSDrying not required/
PC120 degree Celsiusmin. 4-6 hours

2. for 3D printing enthusiasts: buy filament dryer

For whom the oven is not an option, filament dryers are also available. These are especially suitable for 3D printing enthusiasts, but at the same time allow for easy control. Simply place the material in question in the dryer, then set the dryer settings and all you have to do is wait. Modern filament dryers now also offer a sorption unit in which the moisture is absorbed. We have clearly listed three suitable specimens below:

BCN3D Smart Cabinet: The BCN3D Smart Cabinet is another addition to the Epsilon ecosystem. This can be connected directly to a BCN3D Epsilon printer and provides effective protection against moisture in the filaments. Furthermore, the dryer provides a fuse against power failures and can accommodate up to four large coils weighing up to 2.5 kilograms.

Ultimaker S5 Material Station: The Ultimaker S5 Material Station is primarily suitable for spools weighing up to 750 grams. Up to six coils can be easily loaded, and various settings can be made at the same time for optimum drying.

PrintDry filament dryer: The PrintDry filament dryer primarily impresses with its comparatively low price and simple operation. The desired temperature can be easily set, and the dryer has space for up to four coils.

3. dehydrator for drying filament (and fruit?)

Automatic dehydrators are actually used primarily for drying fruits. However, resourceful 3D fans have found that they can also be used to dry filaments. The advantage over ovens: temperatures are maintained better and more solidly, deviations and fluctuations are rare. In addition, the automatic dehydrators usually offer much finer settings in the lower temperature ranges. Overall, the operation is smooth and simple, at the same time, the dehydrators are often cheap to get.

However, it is important to note that if you use your dehydrator for your filament, you should not use it for drying fruit afterwards. If you want both, the favorable price is of course relativized due to the double purchase.

Preventing moisture: How to store filament correctly

To prevent moisture or to protect your just-dried filaments, you should store them properly. This means, first of all, that your rolls are stored in an environment where you can regulate the humidity. For example, various drying boxes from the 3D trade come into question. Likewise, you can also resort to airtight boxes with desiccant bags or similar.

We also advise storing the filament in a place that is as dry and dark as possible. Also, the sun's rays can damage your material.

Conclusion: Filament drying is easily possible

If filament is not stored properly, this can quickly absorb moisture. With serious consequences for your printmaking. A wet filament can lead to unsightly side effects, but it can also seriously damage your printer. The good thing is that if your material is damp, you don't necessarily have to dispose of it. In many cases, you can dry the filament and use it afterwards without any problems. However, you should pay attention to the exact temperature and that it can be kept constant.

Frequently asked questions about drying filament

Feel free to send me questions about filament drying and I'll answer them here for everyone.

Filament is sometimes supplied shrink-wrapped in silver foil to provide protection from external influences. In many cases, the protective film is even resealable. So be careful when opening the package.

Damp filament can damage the 3D printer and, for example, cause the extruder nozzle to clog. In addition to this, damp filament has a massive impact on print quality.

The moisture content at which a filament can no longer be processed cannot be stated in general terms. Instead, this is based on the hydrophilicity of the material in question. The higher the hydrophilicity, the easier it absorbs moisture and the faster it becomes unusable.

Especially well suited for drying filament for beginners with the help of an automatic dehydrator. If you don't have one handy, you can use your home oven or a filament dryer. Some of the latter also offer enormously easy operation.