For this project I’m going to show you how to convert sticky labels and a couple of matches
into a handful of exploding stickers. Put them on a hard surface and hit them with a
hammer, and they explode on impact with enough power to leave your ears ringing. These little
“Thunder Caps” are super cheap and easy to make, and are a fun way to level up your
target practice as well. Because with “Thunder Caps”, your targets explode.
All we need to start this project is a box of safety matches, and a razor blade. The
box-cutter I’m using has a quick release feature for removing the blade inside, and
that’s what I’ll be using in a couple of minutes.
Now let’s get to work making our improvised cap gun powder, with the heads of two safety matches.
Matches like these are around 50% Potassium Chlorate, mixed with a few other ingredients
like sulfur, starch, and glue.
If we take a hammer and lightly tap the heads of the matches, while slowly rolling the sticks
around, you can see the pyrotechnic shell separates from the stick, and flakes right off.
You might have noticed I’m collecting the match heads on a paper sticky note, and that’s
mainly to help keep my brick clean, but it’ll also make it a lot easier to capture and transfer the powder, later on.
Now our “Thunder Caps” are going to make a much bigger bang if we grind the chunks
down into a really fine powder. And a really easy way to do that with a kitchen knife.
Crush them with the blade, then carefully spread the powder back and forth a few times,
like you're putting butter on a muffin.
In less than a minute, you’ll find you have an extremely fine match-head powder, that
should look something like this.
Alright it’s time for the second ingredient, that makes all the explosive magic happen.
And you’ll find it right there, on the side of your matchbox.
Take your razor blade, and slowly and carefully, begin scraping the side of the box so you
can harvest some of the fine red powder. And keep a sticky note, or a piece of paper under
the box so you salvage as much of it as possible.
This precious powder is about 50% red phosphorous, mixed with a few other abrasive materials, like powdered glass.
Use your blade to carefully scrape the 2 powders into separate lines, but make sure they don’t
mix together yet. Because if they do, they’ll activate, and become come “impact sensitive”.
The recipe I’m using for my cap gun mix is 2 parts powdered match-heads to 1 part “striker strip” powder.
So as a basic rule of thumb, just make sure your green line is twice as long as the red
one, and it should work just fine.
The safest and easiest way I’ve found for mixing the two powders, is by dropping them
into a plastic party cup, and carefully swirling the mixture around for about 20-30 seconds.
This way the composition gets thoroughly mixed, and there’s very little risk of spontaneous
ignition. But that doesn’t mean it won’t ignite.
In fact you should always treat your cap powder with the highest levels of caution and respect,
to avoid setting it off accidentally.
Now hopefully you’ve got some ear plugs and safety glasses nearby, because the time
has come, to bust some caps.
Watch closely as I smack the tiny pile with a hammer, and you’ll see the instant it
makes contact, the power explodes, and vaporizes into thin air.
If you don’t have a hammer, it’s no problem. You can actually set the powder off with anything
that hits hard enough, to shock it.
This amazing composition you’ve created is an improvised version of “Armstrong’s
Mixture”, which interestingly enough, is the same powder used for making cap gun caps.
So that means, now you have the option of reloading old cap gun caps, and making them up to
10 times more powerful. Try using that option with the “Exploding Cap Darts” we made in a previous video.
Now just for fun, why don’t we take this experiment one step further, with a pack of sticky dots.
I found a bundle of over 300 sticky-backed labels, from the stationary section of my local grocery store.
Set one of the labels down on the table with the sticky side facing up, then use something
like a modified drinking straw to carefully transfer a tiny bit of the cap powder, to the center of the label.
Drop the powder right in the middle, then find another sticker the same color, and carefully
press it down overtop, sealing off the edges, and trapping the powder inside.
You’ve just created a powerful, homemade “Smack Cap”. And if you look closely,
you should be able to see the powder located in the center, ready for action.
I went ahead and made a whole bunch more by adding the rest of the powder to different
colored dots, using the color coding to my advantage.
The green dots have the smallest amount of powder, The orange dots have around twice
as much powder, and the pink dots are as full as I could get them.
Testing them out on my workbench it’s easy to see the difference between the green, the
orange, and the pink dot, which was actually so loud, your ears would have been ringing.
So remember to do the smart thing, and wear ear plugs.
I smacked a cap on a dirty brick, so you can see the shockwave it makes, when it explodes,
then put one of the orange dots inside a leaf to see what would happen if we hit it with
a rock. Apparently, the leaf gets completely obliterated, in just an instant.
For one final experiment I picked up a CO2 powered BB gun to see what would happen if
we tried using our “Thunder caps” for target practice.
I printed off a paper target, and taped a “Smack Cap” to the center, so when a pellet
hits the bullseye, the target explodes.
By sticking “Thunder Caps” to your targets, you’ll get a very gratifying feeling, of
power and accomplishment when you hit your targets dead-on.
These exploding dots aren’t just for BB guns though. They can be used with slingshots,
blow darts, and I imagine they’d probably work with high speed air-soft pellets as well.
But whichever way you use them, one thing is for sure. You’re bound to get a reaction, each time you set one off.
Well now you know how to use a couple of matches and some sticky labels to make an arsenal
of color coded “Thunder caps”.
And whether you use them for target practice, or just for having a bit of fun exploring
science in the back yard, your “Thunder Caps” are guaranteed to be a blast.
Well that’s it for now. If you like this project perhaps you’ll like some of my others.
Check them out at www.thekingofrandom.com