The Original Potato Cannon

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Introduction: The Original Potato Cannon

About: I liked designing and building things long before I became an engineer, now I get paid to do it!

In this instructable I'm going to teach you how to build the original hairspray powered potato cannon. Sometims it is also called a potato gun. Making this cannon takes about an hour and $30. The finished gun can shoot potatoes over 100 yards!!!


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Step 1: The Materials

Building Materials
-5 feet of 1.5" ABS (DWV) pipe
-2 feet of 3" ABS pipe
-A 3" to 1.5" reducer
-A 3" threaded adapter
-A 3" end cap
-A BBQ ignitor (+1 Screw)
-ABS cement

Consumables
-Cheap aerosol hairspray
-Potatoes or similar legumes

Tools
-Hacksaw
-Drill

Step 2: Assembly

-Cut the 3" pipe to about 13" or a size you prefer (the larger the combustion chamber; the more gas; the more boom)
-Make sure the reducer fits over the pipe
-Spread some ABS cement on the inside of the reducer and outside of one end of the pipe, slide the reducer onto the pipe with a twisting method
-Repeat this for the threaded adapter
-Repeat this for the barrel (5' of 1.5" pipe)

Make sure your gluing is done properly, you dont want it to explode.

Step 3: Install the Ignitor

You probably saw in the last step a silver BBQ lighter attached to the side of the pipe, I tried using this, but it wasnt working, so I bought an $8 ignitor.

Drill a hole in the 3" pipe for the metal lead from the ignitor to fit, mount the ignitor using screws provided, you can slop some glue around the hole to make sure there wont be a gap where the flames will shoot out and burn your arm......

In order to create the arc (spark) to ignite the gas, there needs to be a metal contact between the lead from the ignitor and the metal chasis of the ignitor.

If you mounted the ignitor with bolts into the pipe, bend the metal lead to be within 1/4" of the bolt to make a spark,
I however put another screw in from the other side, but had to run a piece of wire from it to the metal chasis.
Both methods will work.

Step 4: You Are Finished; Firing

Let the cement cure for a couple hours.

Firing:
-Unscrew the end cap
-Force a potato into the barrel (this is easier if you sharpen the end of the barrel with a file)
-Pack it down with a broom, make sure its still inside the barrel, and not the combustion chamber
-Spray some hair spray into the 3" pipe for 2-3seconds
-Quickly screw the end cap back on
-Point it at a 45 degree angle to maximize range and push the ignitor

11 People Made This Project!

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530 Discussions

0
1liular
1liular

4 years ago on Introduction

Can you cut the 1.5" pipe to 3 feet ,instead of 5?

0
Teh32Chicken
Teh32Chicken

Reply 15 days ago

I think so, you'll just get less range

0
yarnahoop
yarnahoop

Reply 1 year ago

i think it will still fire fine but the potato probobly just wont go so far

0
FlorinJ
FlorinJ

Reply 2 years ago

Sure you can. It will reduce the range, though.

0
201129120
201129120

5 weeks ago

me and my frend are doing this for our sience project

0
RaduR6
RaduR6

Reply 1 year ago

Drill some holes through the sides of the cap and the end of the combustion chamber so you can stick some nails through. Or just use a ton of epoxy to seal the cap and mount a bottle cap somewhere on the combustion chamber with another ton of epoxy for fast and easy loading, like I did.

0
201129120
201129120

Reply 5 weeks ago

hi frankie

0
rebeccaz4
rebeccaz4

Reply 3 years ago

Consider removing your cap before you shoot it.

0
childebrand2
childebrand2

Question 1 year ago

Does it matter where I put my igniter? Does the spark nee to be towards the back of the chamber?

0
201129120
201129120

Answer 5 weeks ago

yes it needs to be at the back of the chamber

0
201005027
201005027

Reply 5 weeks ago

no it does not have to be in the back of chamber

1
ng_23
ng_23

6 years ago

Also what will any type if BBQ igniter work

0
RaduR6
RaduR6

Reply 1 year ago

I used a bare piezo element from a lighter and it still works

0
Jaynoski
Jaynoski

Reply 4 years ago

Disposable

1
geg13
geg13

4 years ago

Quick question, what's the best way to make a pressure valve so that if I accidentally use too much combustables it won't explode on me.

0
RaduR6
RaduR6

Reply 1 year ago

Drill 3-4 small holes(3mm or so) in the combustion chamber but be careful not to keep your hand near those holes while shooting it. Or you can get a proper pressure valve but it would need a lot of maths to find the right pressure. Or drill a bigger hole, about 7 mm in the chamber and seal it up with epoxy. If the pressure is too high, the epoxy will break and the pressure will come out the hole.

0
yarnahoop
yarnahoop

1 year ago

plz tell me if I'm mistaken or not, but the ignition chamber should be 2ft long right?