This is the answer I get from most people. But then I read about parts falling apart after 6 months so I get skeptical. Thank you for weighing in though I’m leaning towards PLA since it’s easy to work with.
Hydrolyzing is the process that degrades PLA polymers. Poly-lactic Acid is made from glucose that is converted to lactic acid. Then one H2O molecule is removed to form monomers. Then heat is applied to snap the monomers end to end to form polymers. So, it really wants that H2O back but can't get it unless there is enough energy; mostly heat and moisture also has to be present. Bacteria can also chop them apart but again, moisture is needed just for the bacteria itself.
In a lamp, there is heat. Degrading is more possible. It is not very likely, PLA can survive in normal room conditions for years. Best way to protect them is to coat the part first, Paint or clear coat. The latter is standard stuff, you should always have clear coat ready: any parts that are made to be handled, anything to do with hygiene or food, anything that has to endure moisture or heat, or UV: clear coat.
Also if visual quality is extremely important but you also need to do some post processing: clear coat, in that case you can't even touch the part with skin but have to use disposable gloves, and spray it before post processing to prevent your dead skin cells don't end up between layer lines. The outer surface is like it is made of squishy tubes on top of each other, and there is a crevice between each of them. Once dirt gets inside it is VERY difficult to remove it.
So.. get some clear coat. If you live in an apartment, get yourself very large cardboard box, big enough to put both hands inside WITH the object and make yourself a miniature paint booth. Spray the walls of the box lightly with water before use so the walls can capture the very tiny flying particles.
Thank you that is super helpful. I never knew the human body and PLA had so much in common. Clear coat is an easy solution and makes a lot of sense to protect the parts.
I think that knowing a bit about the chemistry makes it so much clearer, pun intended. Fortunately PLA is super simple stuff, it is just "dried" lactic acid. Wonderful material, truly. If you ever happen to cast or do a re-flow you will be surprised how freakishly hard and strong it is. It is in the same class with polycarbonate when it is uniform material. When printed it only weakly bonds to the previous layer and there is a ton of voids left behind. It is melted line of plastic very rapidly attaching to a line of solid plastic. It is so hard that you can use it to make musical instruments and parts.
PLA parts wont just fall apart..
PLA only fails when exposed to heat. And im talking 60c+; then it starts warping/sagging.
But in this usecase there is no way this will happen.
Also it does not like being outside / UV rays will get to it.. But that also takes years..
PLA is one (or if not the) hardest material you can print stuff with. It's the most rigid/strong even.
If you want extra peace of mind.. you could always print it in PETG.. which is a bit more resistant to heat; and is a bit more 'Flexible' when printed.. so it starts to "tear" (Ever bent a piece of plastic and noticed it going white-ish and losing it's form; and then when you keep going it breaks?.. that kinda thing. Vs where pla would "snap/crack" easier.
That totally makes sense thank you. I suppose brittleness is something to consider. I may have to do some drop tests and see what breaks first. The plywood or the PLA??
If you are going that route, the important thing is the printed part may lose strength over time. Keep the lamp on for a long time and then drop it. Expose it to humid air and do the same.
If you are selling these, you may want to invest in an ABS printing arrangement. It is harder to print but it is very durable and will likely not be affected by the light source.
I have a PLA skeleton that has been holding up my grow light for YEARS. This guy doesn’t have screws or anything, just friction ball joints. The parts closest to the light have discolored a little bit it’s still strong as ever. He’s still holding that light and I haven’t found any signs of weakness or fatigue.
As a “bonus”, one of his hands has a black circle where it partially covered one of the bulbs for a while. It got hot enough to smell (which is how I noticed the issue) other than being a black circle, it’s fine.
Not if the pla is out in the sun
Learned this the hard way when I made the wife really cute garden tags. By the time harvest came, they melted enough to bend the stick. Instead of easy to read tags like we had during planting, they had bend over to be flat in the ground.
I have PLA parts that have been in full sun for like 4 years, outside, rain, cold, the whole deal. I've checked them a couple of times to see how they're doing, and I can't tell any degradation at all.
I'm pretty sure it depends A LOT on brand and color. A TiO2 white pigment, or real carbon black is going to have very different performance under UV than a dye based color. The parts I put out there were just cheap white. Got some new black parts out there this year. We'll see how those hold up.
Even if it's out in the sun.. it will last many years before "breaking down". As long as you dont make the walls too thin and make a somewhat solid object. It probably will discolor though.
It might warp if you put it in the desert..
But then also; almost any plastic will get destroyed by the sun over a longer time. Look at your car window seals/plastics under the wipers and headlights that go hazy.
I made a load of geodome hubs and the nz sun wrecked them in a year. But the uv is really high here thanks to the hole in the ozone.
I had made them pretty quick to print though so that probably didn't help but i was surprised how short they lived.
Ye; a hole in the ozone also does not help lol.
Got this little bird "plateau" from PLA outside for over 2 years now.. it still holds up fine.
But it's a model with like 70% infill and really chunky.. so not much that can go wrong.
I printed a replacement plug to stop crap from getting into the hole that the rotary clothes dryer sits in. It's been in use for four years now, it sits in water, gets direct sun and frost and there's no sign of water damage or swelling.
Gorgeous design. I don't know what the total lifespan of PLA parts is, but the PLA parts in my bathroom have been there for several years now and I can't tell the difference from the day they were printed. I wouldn't worry about it.
Thanks! That’s awesome. Thank you for sharing your experience🙏
Not sure for your black PLA that absolutely has fillers. But a local chemical factory calculated that under constant temp of 20° and a certain constant humidity, PLA will lose around 6 percent of its ductility every 15 years. This is not linear and i cant remember what was stated about UV in their calculations.
I will look in my inbox if i can find the report, but you are definitely good in this case
Thanks so much for the insight. That sounds very promising. Do you know what color filament has the least amount of fillers?
Transparent. That's just the raw PLA polymer itself and it's by far the toughest. It doesn't actually print super clear. I use that for any PLA parts that I expect to take some abuse and it holds up way better than any other PLA I've tried.
Not transparent. Natural. The transparent filaments they add other things to try to make them more clear.
Not sure about it. The PLA natural (off-white and slightly translucent) definitely has the least amount of pigment added.. but there is more to polymer design than just the colour :)
That looks fantastic!
If it's for you then PLA and rivets is going to be fine as other people have said. If you're planning on selling them (and I think you should!) then I'd be more cautious.
Boxes get really hot sitting in delivery trucks or sitting in the sun outside of people houses in Arizona. I printed some PLA hangers for my Christmas lights and they didn't last a day outside of my house in December before they warped due to the direct sun (it was the heat, not UV)!
The rivet also is a weak point as it's putting pressure on the PLA.
I'd suggest ASA or ABS over PLA. If you cant print these then pay someone to print them for the first 10 you sell. The extra cost is a few cents and it's not worth a return or disgruntled customer. After that, you'll have probably made enough money for a new printer!
I'd also swap the rivet for a round head, square neck bolt (black would look great) and use a washer and a nut on the inside although you may need to rivet the last side depending on access.
You could attach the sides with small rare earth magnets. This would make assembly super easy, allow you to ship them flat packed and give an even cleaner look.
What an awesome light.
YMMV
Had to look that up lol. Thank you
Lovely. What's your light source?
Thanks! I’m using one of those LED filament old timey Edison looking bulbs. It gets warm but not hot.
Looks absolutely stunning. But is there a way to get in there to change the bulb or is it closed for good once it's assembled? And I'd love to try and make one like that, too. I got a Creality Ender 3 S1 Plus that you can attach a laser to. I already made a lantern (files from Etsy) and a lot of keychains. Photo for reference here:
Would you be so nice to give me a rough workflow of your project or a hint on how I should get started on my own lamp? I already have some basic skills in CAD and probably all the tools I need in order to build one. I just need some pointers on how to get some nice designs and the dimensions and shapes right.
A.) This thing is beautiful and actually the type of thing I’m planning on making. Bravo And B.) this community is very cool and knowledgeable
Thank you so much. And yes I’m learning so much here. So much better than a Google search can return. Very thankful for this community and the shared knowledge.
Amazing! Did you design the Mandela shapes too? If so what program?
Thank you. I designed the mandala in illustrator and modeled the shape along with the corner parts in sketchup.
I think it will last long enough for you to want a change. But if you share the STL we can test it out (?
Is it led light and how many hours it stays on?
What type of room justifies this type of lamp? I love the lamp but can't rhink of a purpose, unless I had a designer come help. Something geometric sitting on a quirky table, like a hexagonal metal tube sculpture or something. Idk I'm out of ideas
Seemingly little known fact: PLA slowly deforms under static load. That means the rivets will loosen over time. It won't come apart or anything, but it might get wobbly after a year or three. PETG and ABS/ASA don't have this issue.
82 years, 9 months, 26 days, 19 hours, 25 minutes, and 52 seconds.
where did you get the dxf files for that lamp design? i love it!
PLA can warp if under a little load. This seems virtual no load. You’ll be fine.
There are many pla grades. Natureworks, the largest producer in the world has several grades of pla. https://www.natureworksllc.com/technology-and-products/products/3d-series-for-3d-printing
Most filaments you find made in the US will use one of these. China’s are usually sourced from the big producer in china so they will have some different properties. Europe you may find a lot of natureworks but there are also sources from several european companies too.
Pla plus from one manufacturer may be Natureworks 350. And other manufacturer may use Natureworks 370 in their plus. So don’t fall for marketing.
Long story short. Your print will be fine but if you are going to start considering your actual materials, then trace down the source and look at those properties. And dont assume all pla behaves the same. I think some youtubers have tested the various natureworks lines.
If you are using the lamp inside, and using an LED bulb, I would imagine that lamp will live a very long time.
Side note, I see these lamp designs pretty often but never seem to find the files for them. Always wanted to try my hand at making one with my small cnc. Where did you source your design (if you didn't make it yourself)?
If you have to question, then you should be already using PETG. or ASA/ABS. It might be okay, and it might last you 5 years or more, but you would have to UV proof that, if you are going to use indecent light bulbs. Also when using those types of bulbs, your PLA might start drooping.
PLA+, which seems to cost about the same as PLA now, has higher heat resistance if that's your worry, and better strength in the force directions applied. You might prefer that over PETG/ABS/ASA.
That lamp and it's PLA parts will out live you.