DIY 3D Printer Filament Dehydrator

Don't waste your money on "3d-printer filament dehydrators/dehumidifiers". A cheap food dehydrator and a bucket will just do the trick.

1. Cheap food dehydrator
2. make sure its large enough
3. make sure the temperature range is capable of your expectations
4. The dehydrator I linked was simply the one I used in this build.
5. I don't print super-demanding materials yet (only PETG & TPU), so the dehydrator only goes up to 158 F (or 70 C)
6. You can probably find an even cheaper dehumidifier at your local stores, amazon tends to be more expensive
7. Large Bucket (5 gallon bucket)
8. You can find these at a hardware store like Lowe's, Home Depot, etc
9. A drill
10. Flush-Cutters (snips/wire-cutters)

Total Cost:

Dehumidifier (≈$36) + 5-galllon Bucket (≈$4) ≈ $40

A lot of filament dehydrators cost almost double that amount, and it they do cost $40, they can only dry/store one 1kg spool of filament at a time. This DIY dehumidifier can store around 4-5 (maybe 6) 1kg spools, or it can dry 2kg, 3kg, and even 5kg spools! And you can reuse the filament dehydrator as a food dehydrator due to this project's non-invasive nature!

Quick note: Some people have simply cut the dehydrator grills to fit a roll of filament inside of them, but it is a lot easier to use a 5-gallon bucket.

Wet filament can cause a range of printing issues that ruin both print quality and consistency. When filament absorbs moisture from the air, the water turns to steam as it passes through the hotend, leading to bubbling, stringing, and popping sounds. This often results in rough, inconsistent surface finishes and weak layer adhesion. In extreme cases, moisture can clog the nozzle or cause under/over-extrusion, leading to failed prints. Certain filaments like nylon, PETG, and TPU are especially prone to absorbing moisture quickly, making proper drying essential.

If you noticed there were ventilation holes in the original dehydrator lid, you've got sharp eyes!

During the dehydrating process, the excess humidity (water vapor) must leave the container (hence, drying the filament). Without ventilation holes, we would simply be circulating the humidity within the bucket + filament, not getting rid of the humidity!

Therefore, we must:

Drill Holes in the Bottom of the Bucket!

The drill bit size does not matter, I used a 5/16 inch drill bit (6-8 mm) to create a ring of holes around the outer edge of the bucket, as well as four holes near the center, as shown in the picture. To be honest, I the exact formation of ventilation holes should have minimal effect on the drying process - as long as the excess humidity has somewhere to escape to, you should be fine!

Now, all you have to do is slap it all together! The bucket should sit nicely in the food-dehydrator base. Gravity should keep it help down, no glue or fasteners needed!

It's Dehydrating Time!

Now load in your filament (ex. TPU or PETG) and run the dehydrator! Be sure to choose appropriate settings:

The time should be around 6-8 hours (and even more for more demanding filaments), and the temperature should be set to 5-10 C (or 5-10 F) under the glass-transition temperature of the material (basically the temperature at which the material turns from hard to slightly soft)

Oh, you're still here?

Let's talk modifications and possible future updates, then!

Note: I haven't done these modifications yet, but if you are up to it (and have experience), go for it!

Modifications

Grouped based on difficulty of pulling 'em off ;)

Easy Modifications:

1. temperature and humidity monitor
2. essentially, take a thermometer & humidity reader (hygrometer) and create a cutout in the bucket (or 3D print a holder) to mount them in. This will allow you to more accurately decide the temperature and humidity

Moderate Modifications:

1. printing while dehydrating
2. you can create a "rotating interior" via using bearings to enable free rotation while in the dehydrator. This can be done using 3D prints (preferably with a higher-temp withstanding material). You can then create designated channels for the filament to exit the dehydrator set-up to feed into your 3D printer

Hard Modifications:

I saw this modification on reddit somewhere, but I can't seem to find the original post

1. Tinkering with the electronics of the food dehydrator
2. The reddit user essentially opened up the food dehydrator, and he modified the electronics so that the temperature could exceed the maximum value provided by the manufacturer (I'm assuming the user was trying to dry very demanding materials)
3. In addition, he added his own thermometer (incorporated it into the circuit), which provided a more accurate temperature reading
4. Please note that doing so poses potential hazards like an electrical mishap and/or voiding the warranty on the product (proceed with caution, everyone!)

With that said,

Happy Printing!

AZ3Dp