Cap Rocket

Picture of Cap Rocket
A cap rocket is a simple tool for aerial mayhem that only takes a couple of minutes to build.
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Step 1: Materials:

Picture of Materials:
2 large bolts
1 nut
Toy gun caps (paper or plastic)

Step 2: Build It

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Thread the nut halfway on a bolt.

Step 3: Shoelace

Picture of Shoelace
Tie the middle of the shoelace to the end of the other bolt. The shoelace acts as a streamer and helps to ensure that the rocket strikes the ground end first.

Step 4: Loading

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Cut free one of the caps and place it bottom side down in the nut.

Step 5: Finish

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Thread the other bolt into the nut until the cap is tightly compressed. Now your cap rocket is ready to throw outside against a hard surface. Use the shoelaces as a throwing handle. Stay well away from parked cars and innocent bystanders. The rocket works best if you lob it as high as you can. This allows the shoelaces time to straighten out any tumble before it hits the pavement.

Possible Modifications: Attach real fins to the top of a bolt.
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 Could you use something other than shoelaces? Like, say, yarn?
Just so you know, the amount of 'propellant' you put  in the space between the bolts determines the force involved in the 'parting', and it takes surprisingly little to bring the bolts to a high enough velocity to cause serious harm.  You will have neither control of the parts as they separate, nor the results!  The reason I think you need to consider this as a project is I know from my own stupid experience the potentials involved here, that and the reminder of the scar on my brother's head where the bolt hit him and put him in the hospital with a concussion. 

There is serious danger in this kind of thing, and if things go bad, 'I'm Sorry' is sort of lame when you've hurt people.  If you have to do this, drill a hole thru the bolts and tie a STRONG nylon cord from bolt to bolt to keep them together as much as possible.  Remember also, what seems a petty incident can get you in serious problems if something happens, and the cops decide to treat this as an explosive device.  Then you get to meet the Feds, and that will be no fun at all!
Colonel884 years ago
Artillery! Lob it over your enemies wall!
i put one on a crossbow
ctz4 years ago
I tried it with shavings off a strike anywhere match but that doesnt seem to work very well, what would work better
Tombini5 years ago
Divet, you are showing people how to construct a bolt bomb I know people that have been hospitalised from making these!
taterkiller5 years ago
try this with a shotgun shell
spaz135 years ago
I have one question about safety. What if the bolts come apart when the pop cap pops?
nathan91175 years ago
it is a sik rocket it worked fine 4 me if u do it corectly
aflacgoose5 years ago
Great idea.
Nice Pics, good instructable, works better with 3-4 paper caps shoved in hole.
Tat is an awesome idea. Very clear instructions and great pictures. I'm totally going outside and doing this right now!
g chord5 years ago
this thing is AWSOME thank you sooooo much
Matt95 years ago
where do you think I could get the materials??????????
Matt95 years ago
WOW, that is so kool I am definitely going to try that
g chord5 years ago
SWEEEEEEEEEEET -Napoleon Dynamite
Wow I use to make these in my younger days with matches.
mnb5 years ago
These are also called Bolt Bombs
where do u get caps? do the caps have mercury fulminate in them?
Gilly0016 years ago
This looks awesome. I was just wondering, how exactly does it work? I mean, does the heat inside ingnite the cap? Anyways, I'm definitly gonna try this!
when the bolts land, they compress and smash the cap and one end flies off, you can do it with gunpowder,flash powder, match powder or any other friction sensitive explosive.
LayneDiy5 years ago
nice im gonna look for those materials.
G.A.Pster6 years ago
hmm what's up with all these weired characters in my post?
G.A.Pster6 years ago
That oneâs a baby, on mine I use a nut thatâs like 2 inches across. much bigger bang ;D. Itâs the white tips on strike anywhere matches that work the red stuff doesnât do anything. Itâs more potent than capgun roll caps. I like using the shoelaces like a bolo so you can throw it higher, that's a good idea Iâll have to try incorporating that on mine.
My dad was telling me about these a few days ago... he used to make them with match heads.
Do you know if they were strike anywheres or normal?
i used to use safety matches to make mine. just make sure the bolts are tight.
He said he scraped all of the flammable stuff (accelerant?) off of wooden matches and put the dust in the nut. From his description, they where strike-anywhere -- but I'm not sure if there is a non-strike anywhere kind of wooden match.
There is, but those don't work.
what happens when it hits the wall?
The whole thing explodes. If I remember correctly one of the bolts gets shot out and make a massive bang.
Not with caps. If you use something a bit more more explosive then it becomes a bolt bomb.
Wouldn't that be dangerous for a radius of ??? feet?
Divet (author)  Robot Brain6 years ago
The loudness of the bang depends on how many caps you have managed to stuff into the rocket. It's not powerful enough to remove any fingers or toes.
(cue maniacal excited teenage laughter) SWEEEEEEEET!!!!!!!!
Evanator446 years ago
dude that is a awsome idea but i made a really loud cap gun out of knex and i used up all my caps. u said paper ones work? Evanator44
I'd say paper ones are even more likely to work -- their's no plastic to blunt the shock.
nagutron6 years ago
Nice photos. Did you take them yourself? If you did, you should do an Instructable on how to take good macro photos like these; lots of people on the site don't know.
There's this... ...and there's an instructable on making a light tent that I'm too lazy to find.
Divet (author)  nagutron6 years ago
You can get some good macro photography results by shooting outside in the shade. If you're inside, shoot right next to a window, use white bounce cards, a tripod and a fast film setting on the camera.
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