3D printer filaments by their nature absorb moisture from the environment when exposed to free air. Once filament is filled with moisture, it produces faulty prints. Thus it is important to know which filament absorbs more water and steps to prevent the moisture absorption.
The filaments that absorb more moisture are PLA, PVA and Nylon. These filaments are hygroscopic and absorb moisture from the air. The filament becomes useless if the humidity is more. All the moisture needs to be removed in order to make the filament usable.
However, there are ways to prevent the filament moisture absorption irrespective of their hygroscopic nature. Keep reading to find out.
List Of FIlaments That Absorb Moisture:
- PLA Filament
- ABS Filament
- PVA Filament
- Nylon Filament
Presence of moisture in the filament can have a huge impact on 3D print quality. Once you start printing the moisture filament, you will start noticing many problems such as nozzle clogging, improper layers, stringing.etc
Almost all of the filaments absorb moisture while few are really worse than others.
PVA is known for highest moisture absorption and should be stored in an airtight box or insulation bag.
PLA is the most widely used filament in 3D printing, it falls under the fairly hygroscopic category. It is made out of organic biodegradable material and hence it absorbs more moisture.
Nylon filament is next in the list of being hygroscopic after PLA. Nylon is known as a strong filament that has an excellent impact and heat resistance. Nylon can quickly absorb moisture and produce degraded objects.
ABS on the other hand also falls under the hygroscopic category. Measures need to be taken in order to prevent it from moisture. If moisture is not taken care of, then it may ruin the quality and clarity of the print.
Will PLA Absorb Moisture?
Yes, PLA absorbs moisture and causes issues in printing quality. When PLA is printed without drying, it causes bubbles and damages the print.
PLA is very sensitive to moisture and absorbs the moisture from the environment quickly. Take suitable measures to protect PLA from moisture.
In places with dry atmospheres, PLA performs at its best even if you leave it exposed. Many users haven’t faced issues even if the spool is left open in the 3D printer itself.
PLA Moisture Absorption: What Problems Does it Cause?
PLA gets weaker if it absorbs too much moisture and the amount of moisture is directly proportional to the moisture in it.
- PLA will get swollen, if it absorbs too much moisture. Printing this wet filament can cause hotend blockage and sometimes may totally ruin the hotend itself.
- It also causes warping and prevents the object sticking to print bed.
- Moisture filament when heated to high temperature, can produce bubbles and steam and interrupts the filament flow. This makes print rough and destroys smoothness.
- It reduces the overall strength of the object and even a small force can break the object.
Filament With Moisture: What Are its Indications?
Below are the methods that are available to find out if the filament has moistened:
- Blobs, Stringing, Rough textures and print imperfections
- Extrusion lines are not consistent
- Overall part strength and layer adhesion is reduced.
- When heated, it produces popping and crackling sounds.
- Flexibility decreases and gets brittle.
If you see any of the above characteristics or symptoms, it means that the filament contains moisture and needs drying.
Drying filament is a necessity in this case and it is explained below:
Should PLA be Kept Dry ?
Yes, PLA needs to be kept dry as much as possible and the best print outputs. It’s not only PLA, all other filaments also need drying. If dot dried, it can cause potential printing problems in the extrusion.
Moisture also causes nozzle clogging and spoils the extruder assembly. Many 3D users recommend keeping PLA in an airtight container while printing in a humid environment.
It’s always better to store filament in a dryer box irrespective of whether it is hygroscopic or non-hygroscopic for better print quality. It saves filament from dust buildup and protects the physical structure.
Are There Any Non-Hygroscopic Filaments?
Most of the filaments absorb moisture and are hygroscopic in nature except for the fact that some absorb less and some are more prone to moisture.
Many 3D Experts categorize HIPS as slight to no moisture absorbing filament. It has less moisture absorbing property.
How To Store Filament Without Absorbing Moisture:
To prevent the moisture absorption of the filament, it needs to be stored in an airtight container along with desiccant packs. These packs absorb the moisture within the container and prevents the moisture reaching deeper till the filament.
Buy a good Airtight Storage Container from Amazon. Based on your print volume and frequency, you can either buy a big container or several smaller ones.
You could also use the Silica Gel Packs which are available on Amazon for a great price. These are known for their moisture absorption property.
Another alternative to store filament without moisture is by using vacuum sealed bags. AirBaker has the best product by name AirBaker Vacuum Storage bags on Amazon with 11,015 ratings(at the time of writing). This product is highly recommended by many 3D users.
Drying PLA, ABS, & Nylon filament! How to do it effectively
In 3D printing, moisture is considered to be one of the major problems and has to be dealt with effectively. As a solution, 3D experts and manufacturers have come up with many solutions to prevent moisture absorption. 2 of the most effective ways of removing filament moisture are as below:
- Filament Dryers
- Food Dehydrators / Ovens
Filament dryers are the best when it comes to drying the moisture filaments. These are specially designed and are capable of removing the filament moisture. This brings back the property of the filament and make it reusable
- Put the moisture filament inside the device and leave it for sometime, the filament should be dry.
- A few 3D printer models include built-in filament dryers to simultaneously dry the filament while it is being printed. This prevents the problems that arise due to moisture.
Many users say that SUNLU Upgraded Filament Dryer Box does a great job in filament drying. It is available on Amazon with the best ratings and reviews.
The SUNLU filament dryer can:
- Simultaneously dry and print the filament at the sametime.
- One can easily vary the temperature settings as per the filament type, its humidity level.etc
- Drying times can be set manually between 3-6 hours.
- It is compatible to dry almost all types of filaments.
- Dry without noise: SIlent Operation
- Device has a 2-inch LCD screen to show the drying time and temperature.
Buying and using the SUNLU Filament Dryer can keep your filament moisture problems at bay. Order today on Amazon
Food Dehydrators and Ovens:
Ovens are a simple solution to dry the filament, but make sure that the oven is accurate and its display and internal temperature matches. If oven produces more temperature than it displays, then filament will melt and get spoiled.
Check the internal temperature using a thermistor and match it with the set temperature. Ensure there is no difference for a successful drying of the filament.
- Be careful while setting oven temperature. Ensure that it should be less than glass transition temperature of the filament.
- Usually, the temperature of the PLA filament is 40-45 Deg C and higher for other filaments such as ABS, Nylon.etc. So ensure to keep oven temperature values to be lesser than these.
- Some ovens will produce less heat initially and get boosted in multiples. Thus check the temperature first and then place the filament inside.
Food Dehydrators are another excellent choice when it comes to filament dryers. They can effectively dry the filaments at low temperatures with less risk as opposed to ovens.
Food Dehydrator can be a great addition to your 3D printing efforts. It also can offer the advantage of accommodating several filament spools at a time.
One food dehydrator that is endorsed by several 3D nerds is Chefman Food Dehydrator. Buy it on Amazon today
I am Ganesh Divte. I work as a Quality Assurance Engineer at Dhruvtara WireTech PVT LTD. I have experience in SLS, DMSL, FDM, and SLA additive manufacturing processes. I am very enthusiastic about additive manufacturing and its potential to change the way we manufacture products. I believe that Additive Manufacturing has the potential to revolutionize the manufacturing industry and make it more efficient and sustainable.