3D printer filaments can last a long time if properly stored and maintained. The lifespan of a filament depends on several factors like the material type, storage conditions, and frequency of use. With optimal conditions, most filaments will remain usable for 12 months or more before degradation occurs.
What affects the lifespan of 3D printer filaments?
There are three main factors that affect how long 3D printer filaments will last:
- Filament material type – Some materials like ABS and PLA are more stable than flexible or specialty filaments.
- Storage conditions – Exposure to humidity, sunlight, or temperature extremes will accelerate degradation.
- Frequency of use – Filaments that are used more often will expire faster than those used sparingly.
Let’s look at each of these factors in more detail:
Filament Material Type
The base material of the filament plays a significant role in determining lifespan. PLA and ABS filaments generally last 12 months or longer with proper storage due to their stability. Specialty filaments like nylon, TPU, wood, or metal composites may start degrading in as little as 6 months. UV-reactive and glow-in-the-dark filaments also tend to decay faster than standard materials. Here is an overview of common 3D printing filament types and average lifespan:
| Filament Material | Average Lifespan |
|---|---|
| PLA | 12+ months |
| ABS | 12+ months |
| PETG | 12+ months |
| TPU | 6-12 months |
| Nylon | 6-12 months |
| Specialty (wood, metal, glow, etc.) | 3-6 months |
PLA and ABS are the most commonly used desktop 3D printing filaments. Both maintain thermal and chemical stability well if protected from humidity. PETG is also highly durable under typical storage conditions. Flexible filaments like TPU and nylon are more prone to degradation over time, but still last reasonably long. Specialty filaments have the shortest lifespans due to the nature of their chemical additives and process of embedding non-plastic materials into the base plastic.
Storage Conditions
Proper storage is crucial to maximizing the shelf life of 3D printing filaments. The main factors to control are:
- Humidity – Exposure to moisture causes hydrolysis which degrades many filament materials over time. For example, ABS and nylon can quickly become brittle if unprotected from humidity.
- Temperature – Storing filaments at moderate room temperatures between 15-25°C is ideal. High heat can accelerate degradation.
- Sunlight – UV rays will cause most plastics to become discolored, brittle, and weakened over time.
- Dust and particulates – Keeping filaments free of debris will ensure optimal printing performance and consistency.
Here are some best practices for storage:
- Keep filaments in an airtight plastic bag or container with desiccant packs.
- Store in a closet, cabinet, or dry basement area away from sources of heat, humidity, and sunlight.
- Maintain room temperature conditions between 15-25°C.
- Do not store directly on concrete floors which can wick moisture.
- Keep dust and debris away by closing the bags/containers.
- Some materials like ABS and nylon may require an additional dry box storage container.
Frequency of Use
How often a filament is used will also impact its lifespan. With each print, a little bit of the material is exposed to elevated temperatures inside the hot end which can contribute to incremental degradation. Filaments that are printed infrequently will last longer compared to filaments used for daily printing. Heavy use can decrease lifespan by up to 50%.
A good practice is to properly seal filament spools after each use to restrict air exposure. Storing partial spools in an airtight bag with the desiccant also helps prolong shelf life compared to leaving filament loosely wrapped on the spool.
How to tell if a filament has gone bad
There are several signs that indicate a 3D printing filament has expired or gone bad:
- Brittleness – Filaments become brittle, grainy, and prone to snapping/cracking when degraded.
- Color change – Darkening, fading, or discoloration from the original shade.
- Odor – An unusual or chemical-like smell.
- Poor spooling – Filament does not cleanly unwind from the spool and tangles/knots.
- Stringing – Increased stringing when printing.
- Clogging – Frequent nozzle clogs while printing.
- Poor layer adhesion – Layers do not bond properly.
- Reduced strength – Printed parts are weaker and prone to breaking.
Degraded filaments may still print, but suffer from a variety of issues that reduce print quality. Brittleness, color changes, and odor are early warning signs before severe performance problems emerge. If a filament displays any of these negative changes, it should be replaced.
Does filament ever expire if stored correctly?
Yes, all filaments will eventually expire even when stored optimally. The shelf life is extended significantly with proper storage, but degradation will still slowly occur over time.
Most high quality PLA and ABS filaments last 12-24 months before gradual deterioration. Eventually moisture permeates packaging, reactions slowly alter the polymer chains, and material properties decline. So filament does have an expiration date, but optimal storage conditions can maximize lifespan.
Many filament manufacturers will print the production date. It is advised to not keep filaments much longer past 12 months from this production date, even if properly stored. As they approach 18-24 months, the risk of degradation increases.
Nylon, TPU, and specialty filaments have shorter lifespans around 6-12 months. PLA and ABS can usually last several years if kept sealed with desiccants. But all filaments will eventually expire and need replacement.
Tips for extending 3D print filament lifespan
Here are some helpful tips to get the maximum lifespan out of your 3D printer filaments:
- Store in sealed airtight bags or containers, along with desiccant packs.
- Maintain cool room temperatures between 15-25°C.
- Keep out of humidity, direct sunlight, and heat.
- Limit exposure to dust and debris.
- Use up filaments within 12 months of the production date.
- Re-seal partially used spools in airtight bags.
- Avoid temperature fluctuations – allow new filament to acclimate before printing.
- Consider a filament dryer if printing in high humidity environments.
- Vacuum seal portions not being used for long-term storage.
Following these best practices will keep 3D printing filaments fresh and prevent premature degradation. Be extra diligent when storing more sensitive materials like nylon, TPU, and specialty filaments.
Reviving old 3D printer filaments
Is it possible to revive filaments that have absorbed moisture or degraded? In some cases, yes – dried filament can be restored to a usable condition. However, there are limits, and severely expired filament may not be salvageable.
Here are some ways to potentially rejuvenate old 3D printer filaments:
- Dry in a filament dryer – Heating to 45-80°C for 6-12 hours will remove absorbed moisture.
- Dry in an oven – Low heat around 45°C for several hours may drive out humidity.
- Vacuum sealed drying – Use a vacuum chamber or food sealer with desiccant.
- Store with fresh desiccants – Desiccant packs will slowly dry out mild moisture over weeks.
A dedicated filament dryer with temperature and time controls is ideal. Ovens, vacuum sealers, food dehydrators, and desiccants can also have limited effectiveness. Avoid temperatures over 80°C as this can accelerate degradation.
While drying aged filament can help temporarily, it often remains brittle and prone to rapid re-absorption of moisture. The polymer chains have still been damaged. So revived filament should be used quickly and results may still be mixed.
Disposing and recycling old 3D printer filaments
Over time everyone accumulates expired, degraded, and unwanted filament spools. Instead of throwing them in the trash, consider these disposal and recycling options:
- Recycle through local plastic recyclers – Many accept clean 3D printing plastics like PLA, ABS, PETG, and nylon.
- Return to filament companies – Some will accept returns such as eSun and Matterhackers.
- Donate to schools – Many schools with 3D printers welcome donated filament.
- Repurpose for sculptures and arts – Upcycle bad filament into DIY projects.
- List for free on local exchanges – Offer on Facebook groups, Craigslist, Nextdoor.
- Convert waste plastic into filament – Use DIY or commercial plastics recyclers.
The easiest option is checking for local recycling centers that take 3D printing plastics. Or consider trading in older supplies when purchasing new filament. Schools, makerspaces, and hobbyists may also take donated material for projects and experiments.
Bad filament doesn’t necessarily need to end up in the landfill. With a little creativity, expired spools can find alternative uses.
Conclusion
With optimal storage conditions, most standard 3D printing filaments will last 12 months or longer before degradation occurs. PLA, ABS, PETG, and similar materials have the longest shelf life. Specialty filaments degrade faster. Exposure to humidity, heat, and sunlight will accelerate filament expiration.
Proper storage in sealed bags or containers with desiccants is critical to maximize lifespan. Used filaments will expire faster than sparingly printed materials. Signs of degradation include odor, color changes, brittleness, and print quality issues.
While all filaments will eventually expire and require replacement, following best practices allows enjoying consistent printing for many months. Reviving methods like drying may temporarily restore expired filament. But degraded plastic will never fully return to its original state. Expired spools also don’t necessarily need to become waste. Consider recycling programs or repurposing bad filament for other uses.
