Is Your Filament Dryer Causing Your Filament to Become Brittle? Here’s Why (and How to Fix It)

In humid environments, most 3D printer users purchase filament dryers to address a significant issue: moisture problems. Moisture issues can cause snapping filaments, bubbling, and poor layer adhesion. But what if the very device that you bought to solve these issues is not doing its job properly?

In this article, we’re covering whether or not your filament dryer is causing your filaments to become brittle. If yes, then how does it create brittleness?

Can a Filament Dryer Cause Brittleness?

The short answer is yes. The Internet is full of cases where brittleness happens right after the filament has been dried. Brittleness, in general, means something that easily snaps or breaks instead of bending.

Now we all know that not all of the filaments are super flexible, but even so, they should be able to have a little flexibility after printing. But if a dryer gets rid of it, how come your filaments become brittle? Below are some reasons why.

Overheating

Every filament has a different drying temperature as they’re not created equal. Thanks to them having various ranges to work perfectly, you cannot put a general drying temperature since it will only counter the printing process.

While the manufacturers mention the ideal printing temperature of each filament, here are some of the most common yet ideal drying temperatures based on the type of spools you’re using:

PLA – Prints best between 40–45°C

PETG – Prints best at 60°C

ABS – – Prints best between 70–80°C

Nylon – Prints best between 70–80°C

When the dryer runs for too long or becomes too hot, the polymer chains inside the filament begin to break down. This process is called thermal degradation, which is notorious for destroying the elasticity of objects. Hence, the filament becomes more rigid and brittle, and as soon as they are printed, they are prone to bending a lot.

Overdrying

We all know that moisture is insufficient for certain filaments. However, removing too much water can also be harmful. Here’s why:

Certain filaments, like PVA and nylon, are hygroscopic, meaning they contain small amounts of absorbed water.

The water actually contributes significantly to the overall flexibility.

After we overdry them, they lose their natural balance and become way too stiff.

This results in snapping during printing, ultimately defeating the whole purpose of drying.

The amount of overdrying depends on the filament itself, but let’s say that anything more than 12 hours with high heat could potentially damage the filaments. Therefore, the best thing you can do is follow the manufacturer’s instructions for a specific filament and dry it accordingly.

Uneven Heat Distribution

The magic happens inside the dryer, but not all dryers achieve maximum efficiency at all times. You see, some cheaper models, though they would save you some money,  would come with a trade-off that they wouldn’t work efficiently.

This is because the heat distribution would be inconsistent, and some parts of the spool would get hotter than others. But why is this a problem? You see, when one side of the spool stays slightly damp and the other side overheats, some parts of the filament would become brittle.

The result? A spool that is inconsistent, unreliable, and would produce random results that you can never rely on. Cheaper products to get the best possible results.

The Fix? A trusted filament dryer that won’t hurt your spools

A filament dryer like the Chitu System FilaPartner E1 is the perfect blend of affordability and functionality. It allows you to dry up to 4 different spools simultaneously, making it ideal for multicolor printing and even more complex prints that require multiple filaments.

Moreover, you can adjust the temperature while also monitoring it for the perfect drying experience. There are safety measures in place to prevent your print from being ruined, rather than helping you become better at 3D printing.

Repeated Dry Cycle

Some users dry the same spool multiple times, and that could be an issue. You see, the whole mentality of thinking that the drier the spool, the better it is, is completely wrong. However, some filaments are not infinitely resilient and will break if something like this occurs.

With each heating cycle, you are weakening the polymer structure slightly, and after a few cycles, the filament will end up losing its flexibility permanently. Therefore, you should always dry the filaments once and then store them correctly. Only redry if necessary because otherwise, you will have trouble with brittleness.

Dryer Malfunction

Lastly, let’s go to the hypotheses. If the temperature sensor misreads the chamber’s heat, your dryer might be the problem. It could run hotter than the display indicates, and similarly, if the fan fails, hot air doesn’t circulate evenly. This leaves the parts of the spool exposed to direct heat, ensuring that your filament spools will produce brittle results. Both conditions can lead to localized overheating, making some portions of the filaments brittle.

Top Signs Your Filament Has Over-Dried or Overheated

The filament snaps easily when unspooled.

Dust particles start forming whenever you bend the filament, even the slightest.

Prints show that there is weak layer adhesion, or they also break apart easily.

Filament feels more towards the rougher side and is not smooth.

Sometimes, there are jams in the extruder that occur when brittle pieces fall off.

If you notice many signs of these, there is a big chance that you have an over-dried filament.

Final Verdict

Having an over-dried filament can surely lead to brittleness with most filaments. However, this is quite easy to avoid since you can keep processes in check, like checking the filament spools before drying on whether they need it or not. Once you do that, you will avoid brittleness in general.

If you’re looking to buy more 3D printing accessories, check out Chitu Systems.