I'm a great fan of the Mythbusters. I know it's quite obvious and not quite original as a first statement - like saying you don't like it to visit a proctologist, NO-ONE likes it - whatever, I love the concept, the teams craftmanship, their creativity, their crazyness, their looks - talking female Mythbusters now - and their inspiring way to explain what they are doing. The Mythbusters rock, and I'd really love to have a couple of beers with them. Good beers. Many.

One of those episodes I'll always remember is definitely 'the one with the tree cannon'.

I know you all watched it. I saw it, too, and I wanted it. And I saw it again, and again. For those who didn't: youtube, somewhere.

There was only one problem. I don't have an abandoned naval base in my backyard - in Belgium we don't have naval bases at all since we don't even have a fleet - two upgraded crab catchers is definitely NOT a fleet - neither do I have the money to buy a beautiful trunk and blow it up for fun.

Anyway, I wanted a tree cannon, and so one misty day I decided to make a smaller version.

Since I didn't want people and animals getting hurt and houses blown up after having read this Instructable, I decided to smooth this project even more, and make it do-able for all of you. Especially for all those sweet people who're following my projects, you rock!

I'm not especially into nerf, but a lot of people are. So 'why not make it a nerf cannon?' I thought.

And thus I went into nerf.

It's still freakin' awesome. Really.

Step 1: All You Need Is Imagination

Besides a fan of the Mythbusters I'm also a full-time professional handyman aka a jack of all trades aka someone who's getting payed for being McGyver all day long.

So I know a few things about a lot of stuff. I know how to be nice to people, even when they're totally wrong. I know how to carry three toolboxes and a ladder, and still keep on smiling. I'm extremely creative in finding pooping spots, and how to make all traces disappear. I know how to glow in the dark, also, and how to become incredibly small to enter in clients plumbing systems to search for leaks. Really.

And I also know how to handle a silicone pistol.

Silicone pistols are great to boost your day, and you can modify them very easily into a nerf gun.

So... you'll need such a pistol for this project. There are many sorts of these devices, but any pistol will do the job - you're going to dismantle it entirely anyway.

And also you'll need a piece of a tree - obviously. Preferably a piece with a smaller branch still attached to it, like a big '1'.

Next haveto is a large spring (check out the net or the local scrapyard) and a piece of metal or plastic tube, with the inner diameter just perfect enough to let a nerf dart pass through it.

Your tree cannon is just there, just a few steps away.

Work hard, play hard.

Step 2: From Pistol to Piston

Once you have that nice new pistol, you're gonna break it apart and reassemble it all wrong.

From all the parts, the only things you'll need are the rod & the spring. Exit all the rest.

Let's build that piston!

cut the handle of the pistol
make two grooves in the upper part of the pistol
make a trigger - I used a tool from my angle grinder
insert the 'fork' of the trigger in the two grooves
insert the rod and the small spring
slide the rod all the way through
insert the large spring
feed the chickens
screw one bolt at the end of the rod
test-fire!
clean up an empty silicone or glue canister (very easy!)
sand the piston untill it slides smoothly in the canister
drill a hole in the center of the piston
screw it to the rod
insert the canister in the pistol chamber
organise a 'barrel' - just a piece of tube, warmed up with a heat gun to screw it easily to the canister
ready to rock!

MVI_1145.MOV
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Step 3: It's a Tree Cannon, You Know

And thus you need at least one piece of a tree.

Choose a trunk twice the diameter of the pistol and twice as long, WITH a smaller branch.

Unbark - hatchet & knife, old school - and use rasp, rope or angle grinder to make some nice grooves on the ends.

Feed the chickens again.

Split it wisely in four, remove the middle pie part, reassemble with some steel wire and let it dry outside for a week.

Or do like me: give it a speed dry above the fire place. It won't crack, since it IS already cracked. Fools logic.

Step 4: From Piston to Cannon

Once the wood is free from all that moisture that kept it alive you can give it a blast with the sander. Don't sand it too smooth - it's a cannon, not a steering wheel of a ferrari.

Then you're going to put A into B.

Place the piston on the planks and mark the ends.

Cut some large grooves in the planks with the miter saw and make two large plugs with some scrap wood.

Carve a hole for the trigger and continue the inner adjustments. After some chiseling, a few strong words and a beer or two you'd be able to insert the pistol nice & sweet in its wooden coffin.

Once that's done, you can drill the hole for the barrel and the one for the piston.

To assemble the whole, put the two plugs on the piston and wrap the cannon around this configuration.

Use wood glue between the joints & tight it together with steel wire.