We like to ensure all filament arrives as fresh as the day it was extruded by providing a well packaged box. However how does one keep filament fresh once opened? Since many different environments fluctuate, first we need to understand the main causes before we can take some preventative measures. We will also include some simple ways to restore filament.
A common misconception is that water causes filament to become brittle. The truth is filament including PLA is actually extruded into water to hydrate during the drying process. Without this important process filament wouldn't be flexible enough to spool.
Brittle filament is often caused by the plastic becoming dehydrated due to humidity in the air. Think of filament like dried spaghetti. When you put spaghetti into a boiling pot, it begins to re-hydrate which restores its flexibility (and its tastiness).
Another major culprit of filament become brittle is our favourite star! The sun. The reason? UV light degrades the molecule bonds which holds filament together.
In short. Humid weather and UV light are the main causes of brittle filament.
Sizzling is actually water boiling within the filament. It happens pretty much the moment it hits the extruding chamber due to its high heat, low volume environment. Sizzling is a little more rare, and its commonly caused by a long period of water exposure of which the filament absorbs the water like a sponge.
Dehydrating filament will fix this issue. We recommend using an oven at 80C for 3 hours to essentially remove excess water from the filament.
Method 1 Put the spool back in the box when you aren't using it. This will literally keep it away from UV and most moist environments. We have been doing this for years living in sydney which has worked flawlessly. We recommend keeping the decant crystal bag in the center core hole.
Method 2 Find a suitable Tupperware container and place it in a cupboard away from UV light and moisture.
Things to note: You should only perform the above if the filament becoming brittle is a major issue (bowdens extruder setup). Please be careful not to burn yourself on boiling water.
These are methods which have worked for us in the past. Obviously when it comes to 3D printing, somethings work better than others and it comes down to your personal preference.
If you have any other methods which have worked, we'd love to hear them! Please comment below! Also if you have any suggestions or edits to this article please let us know!