3D Printing - Identifying and Dealing with Damp Filament

3D printing in the UK means dealing with damp filament, primarily due to our weather. In my experience, this is the main reason for many bad prints once other usual suspects have been eliminated. Unless you live in a desert, you will encounter issues with damp filament.

Many of the new super printers like the K1, K1C, K1 Max, K2 Plus X1, and P1P have eliminated many of the print problems of old, certainly since I started printing with a CR10 back in 2017. However, one issue still affecting both new and old printers is damp filament.

Symptoms of Damp Filament

Damp filament can cause several issues during printing. Here are some common symptoms to look out for:

• Underextrusion: The printer struggles to push the filament through the nozzle, resulting in thin or incomplete layers.

• Stringing: Excess filament oozes out and creates strings between different parts of the print.

• Bubbles: You might notice tiny bubbles or steam coming out of the nozzle while printing.

• Popping or sizzling sounds: These noises occur as the moisture in the filament turns to steam when heated, causing layer issues and bubbles in the print.

• Poor print quality: Prints may appear rough, weak, or brittle.

• Clogging: The filament can clog the nozzle due to the presence of moisture.

Why Does Filament Get Damp?

Filament gets damp because it's hygroscopic, meaning it absorbs moisture from the air. Here are some reasons why this happens:

• Material Properties: The polymers used in 3D printing filaments, like PLA, ABS, and Nylon, have a tendency to absorb water molecules from the environment due to their chemical structure, which includes polar groups that attract water.

• Humidity: When filament is exposed to humid air, the moisture in the air gets absorbed into the filament. This can happen even in relatively low humidity environments over time, though it's more rapid and noticeable in high-humidity conditions.

• Storage Conditions: Filament that's not stored properly in airtight containers or with desiccants can quickly become damp. Leaving filament out in the open, especially for extended periods, increases the chances of moisture absorption.

• Environmental Factors: Changes in temperature and humidity can also affect how much moisture filament absorbs. During rainy seasons or in coastal areas with higher humidity, filament can absorb more moisture.

Hygroscopic Filaments – Who are the worst offenders?

1. Nylon: Highly hygroscopic, it can absorb moisture quickly, affecting print quality and strength.

2. PVA (Polyvinyl Alcohol): Often used as a support material for dual extrusion, it absorbs moisture rapidly and needs careful storage.

3. PETG (Polyethylene Terephthalate Glycol): Though less hygroscopic than Nylon and PVA, it still absorbs moisture and should be stored properly.

4. TPU (Thermoplastic Polyurethane): Absorbs moisture, affecting its flexibility and print quality.

5. PLA (Polylactic Acid): Slightly hygroscopic, it can absorb moisture over time, leading to poor print quality if not stored properly.

6. ABS (Acrylonitrile Butadiene Styrene): Less hygroscopic than others but can still absorb moisture, causing printing issues.

Preventing Damp Filament

Prevention is always better than the cure. Here are a few tips to prevent your filament from getting damp:

• Store Filament Properly: Keep your filament in an airtight container with desiccants like silica gel to absorb moisture. Vacuum-sealed bags work well for this purpose.

• Use a Filament Dry Box: A filament dry box is designed to keep your filament dry while you're using it. Some 3D printers even come with built-in dry boxes.

• Avoid Humid Environments: Store your filament in a cool, dry place. Avoid leaving filament out in the open for extended periods, especially in humid environments.

• Consider Your Printing Environment: Many hobbyists use garages or spaces that are not always heated and may be prone to damp. Try to move your setup to a better location or improve the environment you have.

• Regularly Check and Replace Desiccants: Silica gel and other desiccants lose their effectiveness over time. Make sure to check and replace them periodically to ensure they continue to absorb moisture.

• Drying Filament: If you suspect your filament has absorbed moisture, you can dry it using a filament dryer or a conventional oven. Set the oven to a low temperature (around 45-50°C or 113-122°F) and let the filament dry for several hours. I will discuss my recommendations later.

• Use Filament Spool Holders: Some spool holders come with covers to keep the filament dry during printing sessions.

• Consider Your Printing Time: If using a spool roller, your filament may get damp while printing, depending on where and how long you are printing. Some prints can take hours or even days.

Cheap and Easy Solutions

I have used many variations of dry boxes over the years with various levels of success. DIY filament dry boxes are very effective and an inexpensive way of keeping your filament dry.

• Sealed Cereal Containers: These are a great option if you can source the correct size for your filament roll.

• Large Plastic Storage Containers: Also a great inexpensive option. Many of the parts needed to print from the container, such as rollers and desiccant holders, can be downloaded for free.

Hygrometer Meter

Do you know how damp your environment is? Hygrometers are invaluable tools that let you know instantly how damp your environment is and allow you to plan ahead. They are inexpensive and a must-have for any 3D printing enthusiast.

My Personal Choice: Filament Dryer

I recently purchased the Creality Filament Dryer Space PI. If you can afford it, this is the system to get. Unlike some older filament dryers that use a curved element to heat the box, Creality Space PI uses a hot air system that circulates the heat, helping to prevent damage to the filament during the heating process. Creality offers both single and double heaters that you can print from whilst drying if you have the space. I have had a few filament dryers over the years and I'm so impressed with the Space PI that I will be buying a few more.

When not in use, I store my filament in vacuum-sealed bags in a warm, dry spot. You can buy vacuum bag kits online from various sites. Most are inexpensive, come with a suction pump, and can be used repeatedly.

Better management of your filament storage results in less waste, fewer nozzle clogs and better prints. I hope you have found this article useful.

@FloMaster @SkaljicNezir @Shack3D_print @PPAC @CiCi @BigDaddy1985 @Creality Cloud @jajaum3d @MaM @Frikarte3D @IK3D @IL3D @Bibi Aya @1964pezqueens3D @bigovereasy @Big_Daddy @The Dragons Den

Dealing With Damp Filament