Introduction: Compressed Air Cannon

Picture of Compressed Air Cannon

This Instructable will guide you through the steps to build a basic air powered cannon to launch things such as water balloons or t-shirts. Measurements for the air tank and barrel lengths, found in steps 2 and 3, are the dimensions that we found to work well, but are meant only as guidelines. 

Notice: Please be safe when following this Instructable. Use tools safely; do not to over-pressurize the air tank and never aim or fire projectiles at anyone or anything. We are not responsible for any injury or damages you cause as a result of using or building this air cannon.




Step 1: Materials & Tools

Picture of Materials & Tools

Materials Needed:
5’ section of 3” PVC schedule 40 pipe----$5.93
1 3” PVC End Cap----$3.63
2 3”-1.5” PVC Reducers----$2.64 each
2 1.5” PVC-DWV Trap Adapter – Spigot Connection----$0.83
1 1.5” Ball Valve – Threaded----$9.71
1 Metal Tire Fill Valve (Bolt-in Type) ----$2.99

Materials You Might Have:
PVC Cleaner----$2.58
PVC Glue----$2.44
Teflon Tape (Seal Tape) ----$.058

Tools Needed:
Saw----$3.49
Drill----$14.99
Drill Bit to Fit Tire Fill Valve----$2.38
Tape Measure----$4.77
File----$3.17
Bicycle Pump or Air Compressor
Electrical Tape (optional)
Clamps (optional)

* Note: Prices listed were found at our local Menards and are listed to be used as an estimate only.

Step 2: Making the Air Tank

Picture of Making the Air Tank

A.)
Measure and mark a 6” section of PVC pipe for the air tank.

* Note: It is helpful to measure in multiple places around the pipe and use a strip of electrical tape to mark a straight line.

B.)
Cut the air tank section off using the saw.

C.)
File the cut edge of the air tank with the file until all sharp edges are removed.

Step 3: Making the Barrel

Picture of Making the Barrel

A.)
Measure and mark a 24” section of PVC pipe for the barrel of the cannon.

* Note: It is helpful to measure in multiple places around the pipe and use a strip of electrical tape to mark a straight line.

B.)
Cut the barrel section of the cannon using the saw.

C.)
File the cut edges of the barrel with the file until all sharp edges are removed.


Step 4: Installing the Fill Valve

Picture of Installing the Fill Valve

A.)
Drill a hole in the center of the air tank for the tire fill valve with the drill.

* Note: Drilling the hole in the center of the air tank ensures that the end cap will not
cover any of the hole.

B.)
Following the directions for installation of your tire fill valve, found on the valve packaging, place the fill valve into the
air tank.

Step 5: Capping the Tank

Picture of Capping the Tank

A.)
Following the directions for your PVC cleaner and glue, attach the PVC end cap on to
the back side of the air tank.

B.)
Following the directions for your PVC cleaner and glue, attach one of the PVC reducers
to the other end of air tank.

Step 6: Attaching the Ball Valve

Picture of Attaching the Ball Valve

A.)
Following the directions for your PVC cleaner and glue, attach one of the PVC male
threaded adapters to the reducer on the air tank.

* Note: Make sure that the threaded side is showing.

B.)
Apply the Teflon tape to the threaded section of the air tank.

* Note: To apply Teflon tape- Start at the tip of the threaded fitting and wrap clockwise, partially overlapping each layer, until you reach the base of the threading.

C.)
Screw on the PVC ball valve.

D.)
Apply Teflon tape to the other PVC male threaded adapter.

* Note: To apply Teflon tape- Start at the tip of the threaded fitting and wrap clockwise, partially overlapping each layer, until you reach the base of the threading.

E.)
Screw the PVC male threaded adapter to the available side of the ball valve.

Step 7: Attaching the Barrel

Picture of Attaching the Barrel

A.)
Following the directions for your PVC cleaner and glue, attach the remaining PVC
reducer to the available end of the PVC male threaded adapter.

B.)
Following the directions for your PVC cleaner and glue, attach the barrel to the
available spot on the last PVC reducer.


Step 8: Firing the Cannon

Picture of Firing the Cannon

At this point, you have fully constructed your air cannon. Before firing, allow the glue to
fully harden and set. Most glues takes several hours, so check your glue
before charging your air tank.

Loading:
Take the bottom 1.5-2 inches of a pringles can and place it in the barrel with the flat side up. This acts as wadding for what ever you may be shooting. This is only really needed for objects that are not a snug fit in the barrel, how ever we almost always use one for best results. After placing the wadding, slide in what ever your projectile is. We enjoy shooting tennis balls and water balloons. We have also used the cannon as a candy, shirt, and confetti launcher.

* Note: Explanation of wadding - Wadding is something that is placed under or around a projectile that is smaller than the barrel size. This creates a seal so that air cannot pass around the projectile with out moving it.

Charging:
Attach a bicyle pump or air compressor and pump air in until you reach your desired pressure. We recommend 50-80 psi. After about 80 psi the distance does not change much. Before trying to pressurize the air tank, make sure that your valve is closed. 

Firing:
We recommend setting the back end on the ground and aiming the cannon at an angle of about 40 degrees for max distance. After aiming, turn the handle on the valve quickly and watch your projectile fly.


Please do not use this air cannon in an unsafe manner. We are not responsible for any injury or damages you cause as a result of using or building this air cannon. 

Step 9: Launch Video

Comments

EddieC13 (author)2015-10-20

how powerful is this cannon?

Masher007 (author)2014-04-28

Danger: See link: This is not spam, but a warning. PVC will fail suddenly after a while. This was band member that hurt badly by a T-Shirt launcher explosion.

See the pictures and never use PVC to hold air, Please.

https://fundrazr.com/campaigns/1Zs3c
..

SeamusDubh (author)2011-03-25

while a ball valve gives you a greater pressure seal. it is better to use a butterfly valve. they open quicker with a higher initial flow bast the valve.

DanTDM (author)SeamusDubh2014-02-02

Get one here:

http://www.nibco.com/Valves/Butterfly-Valves/Cast-Iron-Butterfly-Valves/LC-2000-Butterfly-Valve-Cast-Iron-200-PSI-EPDM-Seat/

Makler 47 (author)2013-05-02

Would you get more distance if you had a smaller (say 2.5'' or 2'' inch) barrel?

ramicaza (author)2011-10-29

holy... please tell me you don't pressurize this to more than 10 psi lol. That cellular core is extremely dangerous along with you're dwv reducers but those are the least of your worries.

igotair (author)2011-06-07

please, please, please, dont use foam core for applications that will be under pressure. never, never, never under ANY circumstances. Doing so is just asking for a visit to the emergency room. i know large diameters of schedule 40 labled for pressure are hard to find, but it is safer to use a smaller diameter pipe and use it in multiples than using foam core.

the mechanical engineer (author)2011-04-17

uhhh... dude. please tell me that the pictures of the air chamber are a mistake and not what you actually used. cellcore pipe WILL explode and is a VERY bad idea. the cannon is a good one ACCEPT for that. please clarify in your instructable that cellcore pipe is not what is to be used. this is VERY dangerous.

About This Instructable

71,702views

90favorites

License:

More by EnglishClassAirCannon:Compressed Air Cannon
Add instructable to: