Are our prints useful in long term?
It's known, that as filament absorbs moisture, it becomes brittle (I saw some videos where filament cracks like dry noodle after being exposed on free air for a while).
What I wonder about is, how about printed objects? Let's say we print something useful (hook, holder, etc.) that needs to fulfill certain strength criteria. If we test it just after printing, it will do the job.. but what after longer period of time? That is, how much strength degrades over the time? We should also keep in mind, that there isn't only static strength of printed object (weight, torque, pressure), but also vibrations and air pollution (UV light, smog, etc.).
Among most used filaments (PLA, PETG and ABS/ASA), PETG seems to be most sensitive to moisture.. does that mean, it also loses strength faster among those three filament types?
To summarize: Are we printing things that can be considered useful in long term? -let's say, to last 5+ years or so? Or are our prints more like a temporary solution?
[Mini+] [MK3S+BEAR]
Robust parts plus reasonable expectations
[...] Among most used filaments (PLA, PETG and ABS/ASA), PETG seems to be most sensitive to moisture.. does that mean, it also loses strength faster among those three filament types?
I printed a set of clips to hold lights and cords up around my deck using transparent PETG a couple of years back. They've been exposed to two New England winters (temps down to 5F/-15C) and summers (recently 95F/40C with 85% humidity) and are holding well. IME, the issue with moisture absorption is producing prints with bubbles and poor adhesion which results in poor initial part mechanical strength. The part is weak to start with. If printed properly, absorption after printing hasn't been an issue in my case. The parts are still quite bendy.
To summarize: Are we printing things that can be considered useful in long term? -let's say, to last 5+ years or so? Or are our prints more like a temporary solution?
Prints that are weak and fragile to start with will certainly only become more week and fragile. My take is that anything designed and printed to be robust is certainly good for a few years use. Most of the commercial plastic or metal products I use outdoors tend to fall apart after a few years, so I'm satisfied with the results.
I haven't done any formal testing, nor have I tried basic techniques like using opaque filaments or applying UV-resistant paints. I don't find that self-printed parts are unusable outdoors.
I'm sure my prints will outlast me by years, decades, centuries, millennia! ...
...the issue with moisture absorption is producing prints with bubbles and poor adhesion which results in poor initial part mechanical strength. The part is weak to start with. If printed properly, absorption after printing hasn't been an issue in my case. The parts are still quite bendy.
-thank you for sharing your experience.
[Mini+] [MK3S+BEAR]
Among most used filaments (PLA, PETG and ABS/ASA), PETG seems to be most sensitive to moisture.. does that mean, it also loses strength faster among those three filament types?
PET lasts for years in the form of bottles, food boxes and the like. I printed some PETG marine fuel pump parts three years ago along with spares... The spares haven't been used yet.
To summarize: Are we printing things that can be considered useful in long term? -let's say, to last 5+ years or so?
I still have some PLA items about seven years old, from before I bought my own printer.
Or are our prints more like a temporary solution?
Some of them are, some are intended to be. Very few plastics last more than a few years exposed to the environment so we should consider repair, replacement and disposal at the design stage.
Cheerio,
Observations
I have lego from the late 1960s. They have been inside, outside, to the beach, swimming pools, mud holes, dates with ugly girls. They are fine. My grandkids are enjoying them.
lots of PET water bottles can be found as curb litter (which I hate with a passion). Never found one that was decomposing or falling apart. Good shake and a wash, probably as good as new.
If you have stepped to nylon or PC, it ain’t going anywhere anytime soon either
PLA, I would not bet on too much. I have had it deform rather quickly just being close to a window.
Bob shared a thoughtful observation. Find a gas grill that lasts more than a season or two. They are out there, but expensive. Whatever you print is a couple of bucks in filament, and quite likely to last a good long time. Save the file, and you can always reprint on demand.
Don’t trust forum advice.
I have plant tags printed in PLA that have been outdoors since July 2019. That is a lot longer than the ones the plants usually come with which crumble after one year.
Kenn
Quality is the Journey, not the Destination. My limited prints->
RE: Mhh...
Mhh... I'd argue that your question kinda depends on the size and how it is being used...
I've 3D Printed my own Dining Light as I couldn't find anything store-bought that would suit my taste but a little later my mom snagged it for herself but with the warmer climate she lives in and my back then inexperience with such large models it turned out the PLA plastic warped like crazy under the forces of its own weight despite the lamp having a set of rebars made out of threaded rods inside.
With my MK2 Dining Light ( since I was again missing one ) I've approached the design in a different way using sections made out of panels bolted to an inner structure instead of just complete sections which greatly improved the rigidity of the lamp despite the size - No warping so far which is promising for a 1:16 RC Tank Project I'm working on.
Basically... The smaller your parts are the less of an issue you'll most likely will have with them - Though that would just be a wild guess of mine.