As a 3D printing enthusiast, you've probably encountered the frustrating issue of your PLA filament becoming brittle over time or maybe sometimes from new spool. This can be a real headache, as it can lead to snapping, clogging, and other printing problems. But what causes this brittleness, and more importantly, how can you prevent it?
The main culprits behind brittle PLA filament is usually moisture or sunlight (UV), and dramatically temperature changes. These environmental factors can break down the molecular structure of the PLA, making it more rigid and prone to cracking. Manufacturers typically wind and extrude their filament directly onto the spool, drying and vacuum sealing it to ensure it remains in good condition. However, once the filament is opened and exposed to the elements, it can start to degrade quickly, or due to ages as clear vacuum bag can slowly let in moisture over longer period. Another factor is some filament add addictive materials to increase stiffness of materials properties or different visual finish which in result cause higher likelihood.
One common mistake that can accelerate this process is rewinding the filament onto a different spool. When you do this, the curvature of the filament changes, and the strain can cause creep failure and fracturing over time. The stiffer the filament, the more likely it is to snap during the rewinding process or develop brittleness later on.
It's important to note that brittleness doesn't necessarily indicate poor quality filament. In fact, some of the highest-performing PLA and carbon fiber filaments are more prone to brittleness due to their increased stiffness and rigidity. This is a trade-off for their superior mechanical properties or different visual finish as most sparkle or translucent filament use addictive for the visual appearance but increase stiffness of the materials properties.
So, what can you do to prevent your PLA filament from becoming brittle? Here are a few tips:
Dry Wet Filament
If your filament has absorbed moisture, you can dry it. Our recommendation is using filament dryer or a dedicated de dehydrator to dry your materials, never use oven or food dehydrator that you use to cook/dry your food.
(More Info: https://support.dremc.com.au/en/support/solutions/articles/51000292935-filament-drying-time-recommendation)
Proper Storage
Keep your filament spools in an airtight container or resealable bag when not in use in medium to long term. Store in dry and not directly under sunlight (uv), some filament may come with re-seable bags or common budget solution is seal large enough food cereal containers with some new desiccant.
Avoid Rewinding
If possible, try to avoid rewinding your filament onto a different spool. This can introduce unnecessary strain and increase the risk of brittleness. This is due to the fact when filament are extruded its still in semi fluid state (not stiff) so it can form to the spool radius, so when you re-spooling this change of state cause higher chance of breakage from larger radius to tight inner start of new spool.
Source: https://www.3dprintingsolutions.com.au/News/filament-rewinding-is-a-bad-idea
Choose the Right Filament
When selecting PLA filament, look for formulations that are specifically designed to be more resistant to environmental factors. Some manufacturers offer "PLA+" or "PLA Pro" variants that are usually more durable and less prone to brittleness. Filament that addictive such as Carbon Fibre/Glass Fibre/Sparkle or transparency had addictive which can increase brittleness, as those materials compromised the materials or stiffness up the materials for better mechanical properties or different varying finishes
By following these tips, you can help ensure that your PLA filament stays in top condition and continues to produce high-quality 3D prints for a long time to come. Happy printing!