Electricity and water are never a good thing to mix, but you never want to be caught out in the dark without a flashlight. Whether you're just a hiker and worried about rain, or prefer to canoe or kayak and are constantly worried about ending up in the drink, a waterproof flashlight is just as cheap and easy to make, as it is to buy.

Disclaimer: Water and electricity are a bad combination. It can short out your equipment, and depending on what it is it can give you a decent jolt. While I have made and tested this flashlight take everything said with a grain of salt and some common sense. Always be careful when putting dangerous elements together.

Step 1: What You Need

A few things to consider. Stay away from self sealing tires. They are lined with a slime that is forced into punctures where it will harden. Needless to say, that would become a horrific mess if you try to cut it. If you don't have any tubes with holes in them you could always consider upgrading and then having the old inner tubes to play with, and if you do have a tube with a hole then you of course want to use a section that isn't pierced for this project.

Flash Light
Inner tube from a bicycle
needle and thread
clear plastic bag
super glue

Utility knife or scissors
any tips on getting the innertue on? mineral oil? is really hard to pushup it on.
roll it up and roll it on like a woman's stocking.
Seems like you'd need a flashlight with a button toggle rather than a switch or twist style on/off mechanism.
Very true. Something I hadn't mentioned because I did have the push button design myself. To note, though: having this design, there is some flexibility in the tubing. It would be my assumption that it may not affect a slide switch, or even a twist. I have managed to adjust the focus of the beam by twisting the cap while it is in the sleeve.
so water doesnt leak in from the front lens of the light?
There is a thin piece of plastic, like a ziploc bag, that is inside the head of the flashlight, covered in step 5. It covers the bulb and actually passes back to the threads where the head screws on. With the head screwed on it seals itself. It may leak in from the front of the lens, but no water gets into the wiring. <br><br>I actually would've preferred the plastic to be external, but I ran into some difficulty with keeping it on, and pulling the rubber over it, so I adapted slightly. I'll try to get around to taking the pictures for that part.
Nifty! Have you tried welding the end together, or does cement work better?
I didn't try welding, because the only decent tool I'd have for that is a soldering iron, and I'd be afraid of not getting a consistent seal throughout. Maybe with a hot air gun that would work. You'd just want to make sure its uniform throughout.
I think he was being sarcastic.
Nope. You can weld metal, plastic, rubber, all sorts of things. Pretty much anything that melts(chocolate!).
lol attempt an arc weld on chocolate!
Now that would be an awesome instructable
LOL no.
I think when he said welding he meant melting the rubber together compared to gluing it. Not anything with welding the flashlight. So it is a good idea if you have the tools to do it right.
if it could be charged while sealed by induction . That might be cool . The gas produced by batteries should be taken into account also in a 100% sealed app . maybe a 1 way valve ?
could you use a hole punch (like the ones you use to file papers to make the hole? a more perfectly round hole will handle stresses better (as well as being one less step for playing with knives), and be less likely to tear. it's been years since i last played with an inner tube, so i'm not sure if the rubber will be too thick for this?
I think it would be more of a matter of can you get the punch around it. The rubber seemed to cut pretty readily with scissors and the like so that shouldn't be a problem.
What if you have one of those goo-filled tubes...and need to replace batteries? GROSS.
use non lubricated condoms<br>
This is a nice trade off between a permanent solution like filling the flashlight with mineral oil (<a href="https://www.instructables.com/id/Hack-a-4-LED-flashlight-into-a-scuba-diving-light/?ALLSTEPS">As seen HERE</a>) and the ultra-quick solution that I used to use which was a non-lubricated condom with the end tied in a knot.<br> <br> Kudos!
I reckon you could do this just as quick using a decent condom. You'd probably have to change it when the batteries went flat mind!
i did this to my mag light (the rubber over the switch was missing when i got it)
I still had the rubber over the switch, but I was pleased that the inner tube actually hasn't effected it. That was my biggest concern; that it'd get stuck in on or off.
cool, any idea how to waterproof a min mag? heat shrink tubing maybe?<br>
You've got my vote!
clever :]

About This Instructable




Bio: Oh wow a lot can change in three years. can't say I forgot about this place but got pushed away from it a little.
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