PLA is not a safe or code compliant material for an electrical enclosure. If you have a metal elncosure inside the decorative PLA cover that would be safe and code compliant in most places in the US.
this post was submitted on 06 May 2026
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If you wrap the wiring in heatshrink insulation, will that be OK, or does the PLA in close proximity to mains cables tend to melt/ignite/otherwise fail catastrophically?
The idea is that if there is an electrical fire it will spread out via the holes in the wall. Fire resistant enclosures are meant to give you time by containing the fire in the wall longer. PLA will not only melt immediately but it will also catch fire and fall to the ground. This will reduce the time you have to safely exit your home. Due to the prevalence of plastics in modern homes you've already got very little time even in a code compliant home.
well then i am happy to not live in the worst country in the world, but thanks for the tip :)
Code is written in blood. PLA is such a terrible idea for an electrical box. No grounding, melt in a heart beat, and then you're just another statistic as your house burns down around you (in a best case scenario)
ok since everyone is so concerned: please tell me and educate me on how a lamp would catch on fire? (just based on the 3 images you see in this post without knowing what country i live in, how wiring of the lamp is done and what safety-precausions are in place electricity wise)
Listen man, you do what you want. I've done some sketchy stuff myself.
Most people don't care that it's illegal, heck most people on here are pirates anyway.
People care about you, and they want you to understand the danger of what you're doing.
Most of them aren't judging you, I'm certainly not.
Will using PLA for a light enclosure definitely cause a fire? Probably not. The odds are very low. In fact the odds are very low that normal wiring in a normal enclosure will overheat. You'll likely never see it.
The problem is the what if. The chance. IF the wiring shorts out, overheats, whatever. A normal enclosure might contain it completely. Or at worst it will resist catching on fire, and fill your house with smoke first, giving you time to realize what's happening and save your life.
PLA will do neither of those things. It will in fact do the opposite. So in the admittedly rare chance that your wiring falls, and gets hot, PLA will actually readily ignite. And then, worse, it WILL drip flaming plastic onto the floor, causing it to spread immediately and without warning.
Your time to notice a fire and save yourself goes from minutes to seconds. It's potentially the difference from waking up to a smoke alarm and a smokey house, to waking up to a smoke alarm and a wall of fire blocking your only exit.
I'm not trying to be extreme, it's just the facts. That's why people say codes are written in blood. The wrong plastics have been used before, and people have died, so now in many lands it's a law.
No one is making you follow the law. They just want you to be informed, so that if you choose to continue, you do so without ignorance to the risks.
I wish you well.
Edit:
Now, if you changed the configuration of the lamp, if you put all the AC wiring and DC conversion circuits in a metal enclosure, and then ran low voltage wiring to low voltage bulbs, that would be still unwise, but significantly safer.
The concern is that AC circuits, while only using enough power to run a lamp in this scenario, have access to more than enough power to run a space heater. If your AC wiring becomes a space heater in your ceiling, nothing will stop it, and PLA will make it worse 🤷♂️
thanks for this long explanation. I get the gesture but I just think that is really stupid to asume something is wrong with a design just by looking at a collection of 3 pictures. For example you are not able to look inside the encloser (on the picture) so you wouldnt know if it was lined with anything fire stopping or not. All the first comment did was stating something they couldnt even really see.
That PLA is THIS dangerous wasnt that clear to me but since I dont live my whole live in fear I never really thought about this.
but as I said at the top, thank you for your long explanation that was way better then the first post, that started this nonsence argument. I will reconsider the encloser.
Since I chose the silver PLA for design reasons: would it be enough to (for example) use this special filament from prusa to just print an enclose that is placed inside the PLA one?
No worries, glad I could help.
I understand the frustration, I've had people do the same thing to me, make assumptions about what I was doing, putting words in my mouth and impugning my motives.
Text is hard to convey proper emotion, and even harder when you've got a bunch of people only typing half of their thought 🤷♂️
As for the design change, I honestly don't know. It's not actually my area of expertise, I just know enough to know what not to do.
I do know that the highest risk is in the connections themselves. A pair of insulated wires are unlikely to ever be an issue on their own, but where you connect the wires to the wiring of the house is the real issue.
Connections can loosen over time, through temp cycling or whatever reasons. And when they loosen, resistance goes up, and heat is generated.
So if it were my project, I'd probably try to find a small round electrical box that fits inside the decorative one. Either metal or the proper plastic. And then make those connections inside that box, and call it good enough.
Maybe make sure the edges of the pipe are smooth where the wires enter them, too, so the insulation doesn't get shaved off when you're moving it around.
Otherwise I really do like the project! Looks great! I hope you come up with a solution you're comfortable with 👍
hm that could be a good idea with the premade enclosure.
thanks again :)
Fire will kill you no matter what country you live in. And it will kill you a lot faster if the only thing between it and you is PLA.
It’s not even like a non-American company has gone out of their way to make a fire resistant materials, for electrical boxes.
If you get some PETG V0 or ABS V0, that will be perfectly safe and probably up to code. That shit can self extinguish when it catches on fire.
A lot of the hardware fixtures in my mom's house are actually made from pieces of plumbing like that. Her towel bars, toilet paper holders and such were all put together by her in the plumbing section of a couple different hardware stores in town.
She likes that rustic/industrial look.
She was probably steam punk before steam punk was cool.