Experiment in the Outdoors: 3D filaments Pt. 2
How well does 3D printing filament last outside?
In August 2016 I attended the Tiny Home Jamboree in Colorado Springs, Colorado, and was inspired to start a 3D printing experiment. As I presented 3D printing to the tinny home community, the attendees asked the question “How long does the plastic / filament last outdoors?”
I did not have a ready answer at the time, so I decided to conduct a informal experiment on my own.
In a previous blog I described the procedure I used to 3D print and mount a series of test samples on a piece of 2 x 4 pine wood.
The experiment started September 23d, 2016 as I put the sample board outside against the east side of the house. It turns out that part of the house was partially shaded at dawn, so latter in July I moved it to a North facing section of our fence to get a full 8 hrs of direct sunlight.
The board did fall down a couple times through the year, and one of the sample chips was cracked after the fall.
As the months rolled by I did notice that most of the samples lightened in the sun, and others warped and curled depending on the temperature that day. It seemed that hanging from a deck screw may not have been the best way to display the samples in the sun. If I do this experiment again I’d make sure the samples stay affixed flat to the board.
Below are the results for each of the brands tested.
Proto Pasta provided samples of their exotic filaments for testing earlier, and are reviewed in various blogs.
Aromatic Coffee High Temp PLA: Both of the coffee based PLA’s tested in this experiment lightened significantly.Proto Pasta Coffee HTPLA
showing the origional color (L) and weathered (R) sample. Photo by Author
This coffee based filament went from the original rich honey brown to a tan / buff color.
Conductive PLA: It lightened slightly, and warping was minimal.
Polished and unpolished stainless steel: Both lightened from dark grey to light gray. They also lost the dull gun metal luster that many find to be an attractive property of the filament.
Magnetic iron PLA: In addition to lightening, both exposed samples started showing reddish brown spots of rust. While not as dramatic as the artificial rusting methods I explored earlier, it would show a great patina for artistic prints.Proto Pasta Magnetic Iron PLA showing rusting over the year (Top Sample, bottom is control). Photo by Author
While all the colored samples did lighten slightly, it appears that Colorfabb is treated with UV inhibitors to maintain colors. Transparent Green PLA, clear XT, and Leaf Green PLA/PHA all kept most of their color.Colorfabb samples after a year outdoors. (L to R) Leaf Green PLA, red nGen, tan XT, green transparent PLA/PHA, GlowFill. Photo by Author.
GlowFill PLA/PHA also kept its glow in the dark properties, with a glow that was as vibrant as its control sample.
Polished and unpolished BronzeFill and CopperFill PLA: The exotic filaments did weather, and the polished samples did lose the luster in comparison to the controls.I was hoping that the copperFill would get a green patina, but you will have to use an acid treatment to achieve that.
Carbon Fiber, red nGen: Both of the samples tested retained most of their color, and the carbon fiber was one of the straightest samples tested.
WoodFill and CorkFill: Both of the wood based composite filaments weathered like any other untreated wood.WoodFill (L) and CorkFill (R) on top compared to the controls on the bottom. Photo by Author
Not only did it significantly lighten, but the wood grains also popped up like any other untreated wood. With a rougher texture, the sun exposed samples could be confused for exposed plywood. It was difficult to tell the cork and wood fill apart at this time, as the rich dark brown color of the CorkFill has faded so badly.
Ninja TechTPU weathered.Photo by Author.
The leader in flexible TPU filaments, both Ninja Flex and Semi Flex had their color and luster dull.
In terms of flexibility I did not notice any difference in flexibility between the samples.This is encouraging if you plan to use TPU for any bushings or gaskets outside.
Buzzed (beer based PLA) and WoundUp (coffee based PLA): The WoundUp PLA lightened from a dark brown to a tan / buff color like the Proto Pasta HTPLA. The Buzzed also lightened from a golden honey to manila envelope yellow.
GlassFill (Fiberglass based PLA) lost some of its lime green glassy luster.3Dom USA (L to R) WoundUp, Glass, and Buzzed filament after a year outdoors. Photo by Author.
Other Experiment Samples
3DDPlus PLA, MakerBot PLA: Both did lighten.PVA that took a long time to dissolve, and left a mess on the board. Photo by Author.
Wenton PVA: PVA is engineered to dissolve in warm water as a support material. While it did finally dissolve after 8 months outdoors, it did leave behind bits of PVA on the pine 2 x 4. Even at 6 months the sample was still on the board, and it was not until the heavy rains in March that the sample completely disappeared.
Nanodax GWPP (Glass Wool Polypropylene): This was a surprise. While it kept its natural white color, it also did not warp like many of the samples. This is a surprise after all the grief I went through trying to 3D print it.
Esun PLA, Esun ABS: Both lightened slightly.Prototype Supply PLA (L)that lost most of its pink color. Photo by Author.
INprinting Hemp-based HIPS: This hemp based HIPS darkened from the off white original color to a light manila tan. The hemp fibers inside swelled and stuck up, giving a rough texture similar to the wood based filaments.
MeltInk PLA: The sample took a direct hit when the board fell off the fence and cracked in half, but still showed the same amount of color change as other PLA’s.
Prototype Supply PLA: This economy brand showed the most dramatic color loss of all the exposed samples.
If you are not worried about the color and texture of the 3D printed items, many of them would be appropriate for outdoor use. Most of the exposed samples maintained their shape and rigidity, and can probably be used in outdoor applications for a few years. Weathering and sun damage is the same across the board for all brands of filaments tested.
For tinny homes, 3D printed items would be a great way to make a part that would last outdoors for 1-2 years while you save up for a upgrade. Certainly painting or treating the plastic post-print would help extend the life and appearance of all these plastics.
I’ll set the board back outside and continue the observations, with future blogs covering the long term effects of exposure to the elements.
It was really interesting to see how the different materials hold up. I will have do my own experiments with how different types of post processing affect the materials. I wonder how some of the “annealed” PLAs would fare? I recently used some MakerGeeks Raptor PLA for a small outside statue and I hope it will last.
The proto pasta was suppose to be annealed if I wanted, but I did not find a difference in another blog.
Stan, thank you for the reply. Do you mean you read another blog where that person didn’t find a difference when annealing? Or, do you have another blog post about the durability of annealed vs non annealed plastics?
I did a blog about annealing HTPLA,
Thank you for the links Stan. Reading now!
Lot of great info, thanks
Good to know many thanks
Coolnwess, thanks for doing that test and sticking with it. While I plan on mostly indoor products in the future, it is good to know this info.
so many choices
Nice experiment! I wasn’t aware of so many exotic materials. Yes, I’m still new to this and learning new things every week! It sounds like all the companies make a good product and that’s nice to know! Looks like carbon fiber would be the best for outdoor longevity.
I’m updating the blog now, but carbon fiber did seem the lest affected by the elements.
Great experiment and interesting results – thanks for the efford Stan!
It would be interesting to repeat this with some different materials, e.g. other brands of ABS and the newer ASA, and maybe PETG, PC and Nylon.
As for the current results, can you give us a short info about the warping aspect? Since different brands of PLA can have a different glass-transition temperature (GTT), and the GTT is usually higher for ABS and other materials, it would be good to know if you can keep your printed parts out in midday sun even on hot summer days or if you better put those somewhere in the shade (depending on material/mix).
Depending on the day I observed the samples and the time of the day, I did see some PLA’s curl more or less. I’ve got nylon and PEGT coming in, I’ll have to add them to the board.
They did warp in the sun on warm days when I checked them. I have them in direct sunlight as a worst-case scenario for the filaments. I think with paint or UV treatment the parts can maintain their shape, but further testing is needed. I think the different filaments can be used for temporary or non esential items outdoors, but more will have to be done to develop filaments that can withstand the outdoors. I’d like to test ASA, PC along with nylon and PETG. I have some Nylon and PETG coming in from holiday sales, so I’ll have to add them to the board.
Thanks for the additional insights. I guess a follow-up article sometime later would make sense, maybe focused on some tips and tricks for treating 3D prints for longer outdoor usage…
An impressive undertaking and really well documented results, thanks 😀
Thank You! I”l put the samples back outside, maybe add a few more.
Very interesting article.
Am waiting for your reply on the experiment you did with durability of 3D printed material.
For durability do you mean some sort of Rockwell harness test or other mechanical testing? I don’t have that equipment, just a fence and a lot of sun.
Nice Review of Material’s Durability
Great real world testing, Thanks
Great Idea! But, it would be exceedingly beneficial to have catalogued the temperature and stated temp range and average temp.
Will your next test use other types of filament Nylon as example and for holding the samples on the board use 2 lathe boards top & bottom each (an over lap) running length of board or bunch of Popsicle sticks
I’m planing on adding nylon and petg. I could use the lathe boards, but then I would not see how much they warp.
Nicely done and very informative, thanks.
Very Interesting and informative
Useful Information, now we know what to expect from the materials we use. Thanks
3D Food printing is such a great concept that is paving newer opportunities for the foodies. This article provides quite an interesting information and the experiment surely brought great results.
I am now looking forward to get a food 3D printer for me and print my favorite food items.
Thank you! It has been great to see how the plastics respond to the outdoors. So far they all have faded, but are still recognizable as swatches.
Ok, I’m revising the blog now for the results after 3 year! I’m also adding PETG, hemp, and co polymers! Stay tuned to this site for the results after 3 Years!