For this project, I’m going to show you how to eliminate the fear and panic of losing your car keys, and the frustration of getting locked out by your kids. Especially when your keys, are locked inside with them. Let’s start this project with a 45 lb. karabiner hook magnet, and a bottle of kids vitamin gummies. Save the gummies for your kids because all we’re really after here is the plastic container, and the reason I chose this bottle, is because it’s fairly cheap, and the mouth is wide enough for a key fob, to slide in and out without any problems at all. Now rather than making our own magnetic key box, you might be wondering, â€œWhy not just.
Go to the store and buy a premade case instead?â€�. The answer is that you could, but they aren’t big enough to store transponders and key fobs, so they won’t work very well with newer vehicles. The magnets aren’t impressively strong either. I tested the store bought version on a flat steel weight and found that the most it could handle was 5 lbs â€¦ barely. One the other hand, you can find super magnets at the hardware store, that claim to hold up to 45lbs. Now in practice, I found the most they’re really good for is about 25 lbs. which is nearly half of what’s advertised. But despite the inflated claim, you can still see they’re still at least 5 times stronger, and that will make all the difference.
Now to make a car hero key box, we’ll need our magnet secured firmly to the lid of the bottle, and I found the easiest way to do that is with a flathead screwdriver and a propane torch. Of course if you don’t have a propane torch, you can always use a bbq igniter instead. Get your screwdriver and carefully heat the tip for a few seconds in the open flame so it gets good and hot, then quickly press it into the top of the lid so it makes a hole that’s slightly offset from the center. While it’s still hot, make another hole inline with the first, and you should end up with a nice clean slit right down the center. Now, when your screwdriver’s cooled down a bit, gently pry at the edges of the bottle.
Cap liner, and pop it out so you can modify the underside of the cap. Heat the screwdriver again, but this time, rather than poking all the way through the cap, carefully carve a channel out of the inner plastic lining, around half an inch long on either side of the slit. Take your time and do a good job, because it’s really important that you don’t burn into the yellow part of the cap underneath. With this little channel carved out, go ahead and unhook the karabiner from the magnetic base, so you can flip it over and press karabiner clip down into the cap, locking it into place with the magnetic side facing up.
Now if you look closely at the underside of the cap, it should start to make sense how this is going to come together. Try hooking the karabiner back in place, and you’ll most likely find there’s just barely enough clearance to get it lined up with the hole. But with a little persistence, and some leverage from your screwdriver, you should be able to pull it all the way through. It’s locked together pretty tight now, and that’s really great, because it means there’s very little chance it’s ever going to come off by accident. At this point, you’re pretty much done, so go ahead and clip a spare set of keys onto.
The karabiner, and that’s it. You’ve got yourself a super strong, and weather resistant, car hero key box. That’ll accommodate an emergency set of keys, with room to spare. Now let’s go one step further and give it a paint job. I thought it would be fun to try coating it with some abrasion resistant truck bed coating. This stuff is normally used for lining truck beds, but you can see it gives the bottle a cool textured look, that will help camouflage it a bit, so it blends in better with where we’re going to hide it in a second.
Spray a couple of coatings on the cap as well, because it’ll help seal the gaps around the magnet, and make the whole thing water resistant. Now since your vehicle is built on a steel frame, your super strong key box will stick just about anywhere you want. And if you look around for awhile you’ll see hundreds of little nooks and crannies where you could hide it, so pick a place that works best for you, and your piece of mind. Now the next time you walk out to your car and realize your keys are missing, you don’t have to worry about calling a friend for a ride, or breaking a window to get in.