<p>Any filament except made-to-be-conductive metal infused filaments should be capable of acting as a suitable insulator, but you'll also want to consider things like failure modes under overheating, mechanical damage, whether it might be subject to spills of conductive fluids, etc. These are not so much a matter of filament choice as structural design and safety design on the electrical level (proper fuses, etc.), and may involve compliance with electrical code. I think those questions are outside the scope of 3D Printing SE, but would be appropriate on a sister site like DIY or Electronics.</p>
<p>From the 3D printing side, you might want to avoid PLA unless you can guarantee shutoff if anything exeeds about 55˚C, since you'll quickly get warping and loss of structural integrity past that. Although I do have an under-hood automotive part in PLA (wiper fluid connector) that's held up fine for a few years now. PETG or ABS/ASA would probably be preferable.</p>

CC BY-SA 4.0
2021-11-17T03:46:58.997Z
Thank you - sounds reasonable.   I only have PLA right now, and have never tried printing anything else.  This could be the motivation, and the PLA one can be a draught print.
Criggie
CC BY-SA 4.0
2021-11-17T03:39:50.810Z
2021-11-17T03:39:50.810Z
R.. GitHub STOP HELPING ICE
<p>I have some relay boards which I want to build into a case for my Pi.  The relays are GPIO controlled and will turn on/off things like a 12 volt DC light, and the 240 volt 50 hertz AC printer itself.  The relays are rated for these levels and current draws.</p>
<p>However I would prefer to put the pi and its relays inside a case.  No commercial case exists to neatly hold the relays, so I have to design and print something.</p>
<ul>
<li>What filaments can and can't be used to encase mains voltages?</li>
<li>What other considerations should be accounted for - minimum thickness?</li>
</ul>

<pla><filament-choice><power-supply>
What filaments are appropriate for a case that will contain mains voltage wiring?
Criggie
# What filaments are appropriate for a case that will contain mains voltage wiring?

(Asked by: username_0 on 2021-11-16)

I have some relay boards which I want to build into a case for my Pi. The relays are GPIO controlled and will turn on/off things like a 12 volt DC light, and the 240 volt 50 hertz AC printer itself. The relays are rated for these levels and current draws.

However I would prefer to put the pi and its relays inside a case. No commercial case exists to neatly hold the relays, so I have to design and print something.

* What filaments can and can't be used to encase mains voltages?
* What other considerations should be accounted for - minimum thickness?

**Tags:** pla, filament-choice, power-supply

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## 1 answers

### Answer by username_1 on 2021-11-17. Score: 2 | Accepted answer

Any filament except made-to-be-conductive metal infused filaments should be capable of acting as a suitable insulator, but you'll also want to consider things like failure modes under overheating, mechanical damage, whether it might be subject to spills of conductive fluids, etc. These are not so much a matter of filament choice as structural design and safety design on the electrical level (proper fuses, etc.), and may involve compliance with electrical code. I think those questions are outside the scope of 3D Printing SE, but would be appropriate on a sister site like DIY or Electronics.

From the 3D printing side, you might want to avoid PLA unless you can guarantee shutoff if anything exeeds about 55˚C, since you'll quickly get warping and loss of structural integrity past that. Although I do have an under-hood automotive part in PLA (wiper fluid connector) that's held up fine for a few years now. PETG or ABS/ASA would probably be preferable.

> **Comments:**
> **username_0**: Thank you - sounds reasonable.   I only have PLA right now, and have never tried printing anything else.  This could be the motivation, and the PLA one can be a draught print.  

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