How to Dry & Store 3D Printer Filament: Storage Solutions
Why Should You Keep your Filaments Dry?
All kinds of 3D Printer FIlament are prone to moisture. Polymers can degrade due to hydrolysis, a chemical reaction in which a water molecule breaks a chemical bond.
In other words, when filaments get exposed to moisture, this causes a breaking down of the polymer chain. When this happens, the material properties of the plastic changes.
Why Should You Keep your Filaments Dry?
For filaments, this degradation can be seen when you try to print with a wet filament. There are several issues that can be caused by a filament that has absorbed water:
- Filament becomes very brittle
- When extruding, the molten filament makes a popping sound
- Rough surface of the printed part
- Nozzles keep oozing causing stringy prints
- Weak layer adhesion
Storing your 3D Printer Filament
Several experiences from makers and 3D printer users show various conditions ideal for storing filament. Common filaments like ABS and PLA can be stored in spaces from 30- 50% according to makers. But for more sensitive filaments like PETG, Nylon, TPU and PVA, lower humidity values from 5-30% would be needed to keep them dry and avoid deterioration.
In an experiment by BCN3D, Nylon, TPU and PVA, already started absorbing moisture at 12% humidity, and notable effects on prints were seen at 12% for TPU, 30% for Nylon, and 40% for PVA.
Depending on what region you live, having a storage for PLA or ABS filaments may not be necessary. Moreover, having a print area with air conditioned space may not need containers to keep your filaments.
If you experience issues with wet filament, however, here are some tips to store your filament to keep them dry:
Filament Dry Box
One of the most common DIY filament storage is the Filament Dry Box. Basically, you can use a plastic container large enough to store a roll or several of filaments. You will then add desiccant packs or silica gel into the container to maintain low humidity inside the container.
What You'll Need
What’s good in this storage system is that you can use the stored filament. Here’s what you need:
- Plastic Container
Select a container where you can fit your filament rolls and includes an airtight seal. If not, you can use materials like window or door gaskets that you can paste under the container cover to make it airtight. Moreover, it is also beneficial to choose a transparent container, so that you can see how much filament is left, instead of opening the container often.
- Silica Gel/ Desiccant Pack
- PTFE/ Bowden Tube
- Hygrometer
- Pneumatic Fittings/ Pushfit connectors
You can source PC4 pneumatic fittings in order to create an air-tight outlet from the container to the 3D printer. Drill a hole into the container sized to the fitting diameter, and then fasten the fitting with the right size nut. There is a 3D printed fitting designed for filament dry boxes, which you can see here. All you need is your 3D printer and a rubber band to create a seal.
- 1 in. PVC tubing
- 3D printed tube holder
You need bolts and nuts with these to fasten it to the container. You can find this STL on thingiverse.
- Other 3D Printed Accessories
What to do:
1. Prepare your container. If it does not come with air tight sealing, paste window gaskets under the lid.
2. Try placing your filament in the container and plan out the holes for the tube holder. What you can do is try placing the filament in a way that it does not touch the container floor so it can roll smoothly. Mark the position of the hollow core of the filament in the container. This will help with placing your tube holder. Do these for both sides.
3. Drill the holes for the PVC holder. Make sure that the holes are level vertically and horizontally. If you have a filament holder that can fit the container, that could do as well without the need of drilling screw holes.
4. Drill holes for the filament outlet. Make sure to create a hole that fits the pneumatic fittings. The number of holes will depend on the number of filaments you want to store in the container. Install the fittings then and attach the Bowden tubes.
5. Place the filament rolls in the holder, and wire the filaments out into the bowden tube before closing the container.
6. Place your dessicant in the container. Instead of pouring the desiccant directly on the container floor, it’s better to place them in a small open container, or breathable bags. This is to make your desiccants easier to obtain when you will need to dry them. Also place the hygrometer in the container, making sure you place it where it is visible when the container is closed.
7. Close the container. If you placed your own gasket under the lid, you may need some clips for the lid, which are available for you to 3D print. You’re all done!
Drying Silica Gel
You should dry your Silica Gel once the moisture in the container becomes too humid for your filament. If you have color-indicating silica gels, you can see that the beads turn dark green once they get filled with moisture.
Again, the preferable humidity in your container will depend on your filament, 30-50% is fine for common filaments like PLA and ABS, while a lower humidity range may be needed for more sensitive materials.
Silica gels are reusable, all you need to do is dry them. Using your oven, you can place them in a tray and dry them at 110°C for an hour.
Vacuum Sealed Bags
To successfully vacuum seal your filaments, you will need a double-zipped vacuum bag large sized at 30 x 34 cm, large enough to fit a whole filament spool.
For the pump, you can purchase a mini vacuum storage pump designed for vacuum bags, and are usually battery powered and rechargeable through a USB port. You can use this affordable large vacuum storage bag from Amazon.
To keep the filament dry while stored, place the filament in the bag, along with a packet of desiccant and zip the bag. Finally use the vacuum pump to draw out the air. Make sure you put in a new pack of desiccant, or a dried one, if you are using a pack that came with the filament.
How to Dry 3D Printer Filament
You may have filament rolls lying around which produces bad quality prints due to moisture. Or maybe you were shipped a low quality filament that keeps breaking. These filaments will not go to waste since you can dry them in various ways.
You can have cheap options to dry your filament with a bit of DIY-ing, or you could also go with products dedicated to filament drying at a cost.
Oven Drying
For PLA Filament, you can preheat your oven to 50°C first before placing the filament into the oven. For ABS, keep the temperature around 80°C. The target temperature in dying filament is just below the glass transition temperature.
Food Dehydrator
For a more controlled solution, you can buy a food dehydrator and dedicate it as your filament dryer. These machines come cheap in the market, you can buy one with $30 to $50. This can be a better solution than oven drying since food dehydrators circulate the warm air, and have better temperature control.
To help you select a food dehydrator, make sure you check the dimensions of the filament drier that it can fit the spool diameter. Most of these dehydrators come with trays and mesh layers, which do not fit the thickness of most filament rolls. You can cut the mesh- like base in order to fit another roll or two for spontaneous drying.
Commercial Filament Driers
Matterhackers PrintDry
eBox from eSun
This is a multifunction solution that provides heating and drying, moisture and dust protection, and weighing for estimating filament usage. This also includes presets for drying various filament materials.
This filament storage system also allows filament to be accessible for usage while being stored. However, this system only allows a single spool per machine.
Selecting a Good 3D Printer Filament
To avoid, or minimize, having troubles in your filament, it is best to select a good 3D printer filament. There may be no harm in printing with cheap rolls, but at the risk of quality issues you have to deal with before printing them.
Most often low quality filament arrives with moisture, which can be easily dealt with. However, other issues such as filament diameter consistency, impurities, color consistency and overall quality is unresolvable.
Filament Diameter
Filament rolls with a good quality control indicates the tolerances, with -/+.03mm to be an acceptable value. Low quality filaments do not indicate their diameter variations. When inspected, the filament tolerance exceeds acceptable limits. Moreover, the filament does not stay round throughout.
This inconsistency in diameter can cause inconsistent flow from your hotend, thus resulting in artifacts in your 3D print that are unavoidable.
Impurities
This can be the biggest issue against choosing filament. Impurities present in a filament will not only cause poor prints, but can also cause inconsistent melting. This can then lead to extruder clogging, basically bringing your 3D printer to unexpected downtimes.
Nozzle clogs are very difficult to deal with as it will require disassembly to your extruder, a tedious task that takes time, and even resources as you may need replacement parts once the parts of the hotend become unsalvageable. It is better to stay away from cheap filaments, and spend just a bit more with quality filaments.
Color and Quality Inconsistency
Using inconsistent products for our 3D printing business can result in quality issues and unnecessary troubleshooting.
You may have used a cheap filament before and had a good result. You proceeded to order another set of the same color, however, with no quality control, you receive a filament that is different from what you used previously.
This has been a common issue with cheap filaments. Not only color but inconsistent formulation of filaments can produce troubled prints to your supposedly calibrated settings.
Wrapping Up
Filaments are affected by moisture, with varying degrees depending on the material. To counter the effects of humidity, these solutions can prevent and treat your filament rolls from moisture.
Depending on where you live and how air is conditioned in your printing space, you may need extra steps to keep your filament dry.
Most of all, you can select filament brands that provide a tightly-sealed, high-quality and consistent 3D printer filaments to keep your print operations smooth and trouble-free.
