How Long Does PLA Last? Does It Expire?
Need to know how long your PLA filament will last? In short, when you place PLA under normal room temperature, it can last for a very long time – say 12 to 18 years.
Depending on where and how you store it, 3D printed objects made from PLA can last from a month, to 2 years and up to many years. It can break down at different rates depending on its environment. In this post, we look at how long PLA lasts in different scenarios.
What is PLA Made Of?
Polylactide (PLA), being the most common 3D printer material, is produced from environmentally-friendly raw materials. It’s a cornstarch-based, biodegradable plastic that’s extruded from renewable materials. Aside from cornstarch, some PLA manufacturers use tapioca roots or sugarcane for manufacturing this material. PLA is the most common 3D printer material.
Does PLA Filament Go Bad?
Since PLA plastic is made of plant-based material, one may ask, does it expire? The good thing to know about is that PLA filament does not have an expiry date. But any filament can go bad based on where it’s placed or where it is stored.
For example, the more humid the place, or the more you expose it in direct sunlight, the quicker the plastic will degrade. This may mean the object can deform or bloat and lose its original shape.
Also consider the filament quality you initially buy and how it is packed. The reason why most filament manufacturers deliver filament rolls on vacuum sealed containers and with desiccants is to prevent it from absorbing the moisture.
So while PLA material doesn’t expire like food products, there are factors which may cause this plastic to lose its functionality earlier on.
Factors that Affect 3D Filament Life
What may affect the lifespan of your PLA 3D printer filament? Here they are:
A lot of 3D printing failure and problems can result from humidity and moisture in the environment. Humidity can cause degradation and oxidation in plastic materials.
When exposed in humid places, your 3D printer filament can absorb moisture in just days and cause a number of problems.
This includes bloated filament diameter that causes extrusion problems and filament fragility. The result of a bloated filament heating up is that when it’s extruded, it boils with steam coming out.
2. Mechanical Stress from Unwinding the Spool
Another thing that affects your 3D printer filament life is the amount of mechanical stresses it receives from constant unwinding. Whenever you’re uncoiling a filament from its original position, it induces stresses on the line giving more chances of breaking.
For this factor, just make sure you unwind the spool carefully to prevent the filament from producing cracks.
3. Filament Quality
Depending on your PLA filament manufacturer, some products are more durable than the others. This mostly depends on the way the filament is composed, manufactured, coiled and quality inspected.
If you want to ensure a longer filament lifespan, buy high quality PLA filaments. There are a lot of PLA suppliers offering quality filaments at a budget price. The best way to find them is by reading through reddit and reviews.
How Long Do PLA Prints Last
Next, let’s see how fast (or how long) your PLA 3D prints last in different environments and situations.
How Long Does PLA Last After Opening?
A PLA filament spool that has been opened but stored in a sealed container with desiccants or properly dried can survive for approximately more than 15 years. This is if it’s kept at its recommended storage temperature of 10 to 40C and away from direct sunlight.
- PLA that’s not sealed and exposed to direct sunlight may only survive in 1 year.
- PLA exposed to direct sunlight at ambient temperature can survive for 1 week then it becomes brittle.
- PLA filaments exposed to more than 60% humidity can be usable for less than a month but can produce bad prints.
How Long Does PLA Last After Printing?
How long does a PLA filament plastic endure after being 3D printed? If PLA prints are kept indoors and away from hot temperatures, it can virtually last its lifetime. A good estimation would be 15 years, based on circumstantial evidence. This means 3D printed PLA miniatures or gifts can last for a very long time and are highly durable.
How Long Does PLA Last In Water?
For those of you wondering if you can 3D print miniatures for your fish tank, PLA is okay to use as it’s aquarium-safe. It’s also non-soluble, which means water won’t melt PLA. However, PLA is not water-resistant, which means it absorbs water and decomposes over time.
PLA in water can generally last 47 to 90 days, which is pretty much faster to decompose than PET material. PLA objects in water can even break down faster with high temperatures.
In an experiment where PLA is submerged for 30 days, it had increased in volume and weight at 1% to 6%.
So if you place 3D printed PLA objects in your aquarium, it will absorb water, become bloated and increase in volume. Submerged in pure water, PLA can degrade slower than when the liquid contains microorganisms that eat away PLA compounds.
Hence, if the water is clean, the PLA can only become bloated, and can be fixed by heating it at low temperatures (<50C) or drying it with desiccants.
How Long Does PLA Last Outside?
Since PLA is not UV resistant, it will easily degrade or melt under heat and sunlight over time. However, even though PLA is biodegradable, it doesn’t mean it will make it easier for the landfill to process this plastic.
PLA filament has a yield strength of 60 MPa and can be used for light structural applications. But if you use it outdoors, even with indirect sunlight, it will still be affected by the outdoor conditions.
Hence, while it’s lifetime outdoors may not be as long as PLA indoors, it can still be used for certain outdoor applications. A safe estimate may range from a few months to 1 year.
How Can You Tell if PLA Has Gone Bad?
When PLA has absorbed moisture, you can easily tell it has through several ways. These are through:
- The snap test
- When it’s printing and popping sounds are heard due to moisture
- Poor 3D print quality & Weak prints
Filament Snap Test
If you want to check if your filament is good or if it has not absorbed water, you can do a snap test. Simply bend a piece of filament at 180 degrees and if it doesn’t snap but just bends, then it’s good to go.
Popping Noises During 3D Printing
Small bubbles of steam forms causing the extrusion of filament to sputter and thereby produce popping sounds. In extreme cases, PLA filament that has absorbed excessive moisture can cause printer jams. This means the extruder may not be able to prevail with the steam pressure.
Poor Quality Prints
Due to the above effects on your printer, the print quality may fail or the filament will produce weaker prints.
How to Store PLA Filament
So now that you know how moisture can significantly affect the lifespan of your PLA filament, you must store it in the right way.
There is a high possibility of filaments absorbing water, so store it in a sealed container with silica. In a nutshell, make sure it’s kept dried and away from direct heat and sunlight.
Remember to store and dry your filaments when not in use and avoid leaving it in its spool holder when you’re not printing. This is to make sure it doesn’t absorb moisture and degrade quicker.
Does Other 3D Filament Expire?
Now that we steer clear of PLA, what about other 3D printer filament materials? Does ABS or PETG expire?
ABS is another common 3D printing material. When exposed, ABS can fade over time and absorb moisture. ABS plastic is also hygroscopic like PLA but it’s tougher when maintained dry.
One thing to note is that ABS can fade when exposed with direct sunlight. When it does, it will create hairline spots while 3D printing. This in turn becomes a haven for bacteria that can separate the printing layers over time. The bacteria can also dull your finishing.
When this does happen, you can remedy the situation by coating your ABS prints with a gel coat. You may also wrap it with carbon fiber or laminate it. These solutions can save your ABS 3D prints and you can place them more safely in humid areas.
To protect your ABS spools from deteriorating, make sure they’re kept dry in a container with desiccants inside.
Being a copolyester, PETG is more durable than PLA and ABS which means it’s long lasting. But FDM printed materials made from this material can also expire. If exposed to moisture, PETG filament can degrade over time.
Once again, you can use a container to store leftover PETG spools with desiccant inside. An unused PETG spool can stay up to 1 to 2 years from its manufacturing date.
How Long Does 3D Printer Filament Last?
Other popular filaments like ABS and PETG can usually last longer than PLA. They degrade at different rates depending on moisture and storage conditions. When exposed to humid places, ABS filament can expire in a month. PETG may last 1 to 2 years.
How you also design your 3D print can determine how long it will last. The higher the percentage infill, the thicker it will be and hence, the better chances it can stand against environmental conditions.
As PLA is the most common 3D printing material, a lot of hobbyists and enthusiasts are curious on how long their 3D prints can last. In this article, we’ve shown you how long PLA prints last depending on a variety of situations (under water, outdoors, indoor). So the next time you consider making products with PLA, make sure you consider its shelf life and if it’s appropriate for your project.