Not How To Build an Air Cannon

The web's original air cannon page


Or, My personal experiences building air cannons.
by
Bill Mills

Please note: I don't mind answering questions and discussing aircannon technology in e-mail.  It is annoying however to receive questions that are already answered on this web site.  If you have a question, please make sure you have fully read the web site and FAQs before you e-mail.
CLICK HERE to e-mail me.


Hi all!

Well, here it is, my first html document. This document is the result my spending a Saturday morning in 1993 digitizing a couple of pictures, and then looking at the source of the Amiga Mosaic Home Page (yes, I know that link no longer valid, but it's there for posterity's sake) and popping this together (manuals? We don't need no steenkeen' manuals). This was more an exercise in html for me than anything else, but here goes... Of course there's more to it now then there first was. After it had been up a couple of months, I changed the pictures from video grabs to cleaner illustrations. I've tried to keep the look as faithful to the original as possible, as I like the nostalgic feel. As someone who makes his living in part by web design It's nice to see this page and look back at my "roots".

This web page was the first on the topic of air cannons. It was originally written in Final Copy II on an Amiga 4000, and tested off-line in Amiga Mosaic. This was before I had ppp up and running on the Amiga, so I sent the files by zmodem to their original location at warpig.cati.csufresno.edu (Steve Mitchell's Mac II ci that is no longer online). I'd go to Steve's office to actually see it online.

This page has been stolen and illegally run on someone else's server in an attempt to have a commercial site to sell advertising (that was taken care of by legal action - this is copyrighted material). For those budding webmasters out there who want to copy content to build their site, remember without the permission of the person who created the content, you're violating a federal law by republishing it on your web site. There is no need to copy anyway, you can add a link which will take people to the information. Instead of copying the work of others, put your own material on the web, then exchange links with other pages, and that way we're all working together to share information on the web.

WARNING

This document is not intended to be a guide to go out an build your own potentially hazardous device. This document is a collection of information based on my own experiences building air cannon. What you do with this information is your responsibility, and not mine. Serious injury could result from misuse of an air cannon, or compressed gasses. An air cannon should never be fired at a person who is not wearing the appropriate protective equipment, and has not given consent to be fired upon (such as a player in a paintball game). Even while wearing appropriate safety equipment, an aircannon can still be very hazardous. Paintball goggles are meant to protect against one or two pellet impacts, not 30, 40, or more simultaneously. In my experience (and this will very with each particular air cannon and type of cartridge) anything under 50-60 feet is just too close. Preferred method of use for paintball is lobbing the paint into the air so that it spreads and rains down over a large area, thus marking as many people as possible. Some people one line have advocated gluing multiple paintballs to form a "super ball". Aside from greatly increasing the risk of injury to the target, this makes absolutely no tactical sense. An aircannon is less accurate than a paintball gun. It's advantage comes from covering a large area in a "hailstorm" of paintballs, so that a number of people within that area are hit by one or two balls from a single shot. Hitting one person with a dozen paintballs does not eliminate them from a game any more than hitting them with one paintball (and on most paintball fields hitting a person with more than 2-3 paintballs will eliminate you - for overshooting). All a "super ball" will do is hurt, and very possibly injure the target (paintball goggles aren't built to protect against them).

I can not accept liability for someone applying or misapplying information from this document. The information here is provided for entertainment purposes only.

So what is an air cannon? You ask?

An air cannon, or pneumatic cannon is a large bore device that uses air pressure to propel an object. (Duh!) I find that my air cannon is useful for propelling all kinds of things, from large quantities of paintballs to water, oranges and snowballs.

 Since putting up this web page, I've been contacted by people who have found other applications for air cannon, like launching confetti for theater use, or lofting chemical glow-sticks on parachutes for no-flame fireworks. A fellow named Jeff (he never told me his last name) sent in this guide to making spud-a-chutes. Personally, I've found mine excellent for dousing water on relatives at family reunions, as well as knocking wasp nests out of trees.

You may also be familiar with what are commonly called "spud-guns". These are cannon made of pipe, which launch potatoes, or tennis balls using hair spray, ether, or other volatile, flammable propellants. I have long believed that air cannon were inherently superior, from a safety angle, due to the fact that they don't use fire or explosives. In 1997 a friend of mine, Rob Kaye went to Burning Man in the Black Rock Desert. He took his aircannon, and was interviewed by The Discovery Channel about it, publicizing this web page as the source of his plans in the show (see photo at left by Dave Gross). After firing his aircannon next to people with "spud guns" at Burning Man, Rob reported that the difference in power and range was like night and day. Using a GPS receiver, he recorded potato halves flying over 300 meters.

I don't mind answering questions about aircannons, but please, before you ask, read the web site thoroughly. Chances are, based on much of the mail I receive, your question is answered here. Don't miss the Frequently Asked Questions further down this page:

There have been several air cannon type devices used in the sport of paintball (what's Paintball? Check out the WARPIG , which is probably how you got here anyhow). The Command Post had a small unit that worked off of 12 gram CO2 cartridges. Some other company came out with the "Thud Gun", and another made the Air Power Sabot Cannon. Air Power's system worked off of compressed air, or could be charged from a constant air CO2 tank.

The air cannon I built was the result of several conversations between myself and Cristin Pescosolido. The premise of the air cannon is pretty simple. There is a compressed air reservoir and a barrel. Those two components are separated by an electric sprinkler valve. I fill the reservoir with compressed air, trigger the valve, and what ever is in the barrel is forced out.


For further information, click on one of the air cannon's components


Once I had an air cannon, what could a do with it?

Well, my first and obvious answer was to load a hackey sack in it and shoot it across the room (why obvious, because the hackey sack was 2 inches across). WHAM! It blew up into bits of leather and rice on the wall. Hmm... Next I tried oranges that were about 2". Foomp! Across the orchard in one shot. Then of course I set about putting together a cartridge that could fire 20-30 pellets, and that's when the air cannon got fun.

Using the aircannon for paintball I've found it most effective from a distance against large groups of people. Against one person, it's kind of pointless, a lot of hassle for what a paintgun can allready do. However, at long range, or lobbing the pellets, it can thinly cover a large area, getting a lot of people in one shot. The first day that I used it in a game, I scored 3 eliminations in one shot from a tower as they were rushing the flag.

A friend of mine built this back pack air cannon with the air chamber and valve in a back pack, and the barrel is shown here mounted under the stock on my Nightmare pump paintgun.


Click Here To Return To The WARPIG Paintball Home Page

Or Here To Return To The Bill's World Paintball Page

Frequently Asked Questions and Comments:
 
 

  • Does it work? - Uh, yes.
  • I thought you should know that your air cannon can't possibly work because of xxx xxxxx xxxxx xxxxx. - I though you should know you have no idea what you are talking about because it works just fine, I have built it and used it.
  • That's a cool plan, and much safer than "spud guns", but no where as powerful. - That's not at all what I've been told by people who have fired both side by side. The air cannon is much more powerful. Ever wonder why the Pumpkin Chuckers run on compressed air and not hairspray?
  • I have built an air cannon like yours but it doesn't work/shoots at a low velocity/leaks/etc. What is wrong with it and how do I fix it? - Since I can't see and test your air cannon personally, I don't know.
  • How far can an air cannon shoot? - Using my design a friend has recorded potatoes firing over 300 meters using 130 psi compressed air as a power source (recharged with a SCUBA tank and 130 psi fixed output first stage regulator).
  • How big can an air cannon be? CalTrans (the California Department of Transportation) uses a large pneumatic cannon called an Avalauncher. I've seen them in use in videos about Avalanches on the Discovery Channel. I had previously quoted from one of those videos that the Avalaunchers can fire shells as far as 5 kilometers to break up snow packed cornices. A gentleman from CalTrans e-mailed to inform me that was incorrect. The Avlauncher does not have that great a range, but the LoCat system with a longer barrel and higher operating pressure does. The wife of the Avalauncher's designer also has e-mailed me, noting that the Avalauncher is not available to the general public. I wish I hadn't lost her e-mail during a hard drive reformat, it made interesting reading. She seems to hold a dim view of aircannon enthusiasts. She had asked me to remove the mention of their product from my web site. As Air Cannons are the subject of this page, I felt it was apropriate to discuss here, but if you're looking for an entertainment device, please do not bug them, let them go about their business of putting this technology to work in a way that is saving lives around the world.
  • Can you send me blueprints? - No. There is a fully labled construction diagram on the web page.  I have not created blueprints or construction plans.  As it says above, this page is information about a project I undertook, it is not an instruction manual or construction guide.
  • What kind of silinoid(sic) did you use? - Stop watching "Home Improvement" - Tim Allen says "silinoid", the word is SOLENOID.
  • What kind of solenoid did you use? - The one that came with the valve. Solenoids are available seperately, but they're the same solenoid, just a replacement in case the one on the valve wears out.
  • What kind of solenoid valve did you use? - I used a 3/4" valve with flow control (which I turned all the way open) and a back-check valve (which is not needed. It's "U" layout was perfect for the way I built my aircannon though. I doubt the same model is made anymore, but the Rainbird 075-ASVF is equivalent to the valve I used.
  • Can I use a manual valve? - Yes, a manual globe valve will work, but not as efficiently as a solenoid controlled valve, because it opens more slowly. The electronic valves can also be triggered manually by opening the bleed screw if your batteries are dead. Gate valves will not work, they open too slowly.
  • What length of pipe did you use? - See the diagram.
  • I put together an aircannon, and instead of waiting 24 hours to fully cure like the PVC Cement can said, I charged it up after 10 minutes and it exploded. - Please do not rebuild it, you seem to lack the common sense needed to operate it safely.
  • Can I get more power by concentrating the air pressure using a 1.5" diameter barrel? - Quick physics lesson here. When you reduce the barrel size, you reduce the surface area of the projectile, that means less area for gas to push on it. Example - a 2" barrel has 3.14 square inches of surface area (the area of a circle is pi times the radius [radius is half the diameter] squared - A=pi*r^2). That's 314 pounds of force at a 100psi charge (multiply the pounds per square inch by the square inches to get the pounds of total force). Cut the diameter to 1.5" and the area drops to 1.77 square inches. That's only 177 pounds of force at 100psi. Drop the barrel diameter by a half an inch (25), and and you cut the energy put on the projectile by 48%! On the flip side of the coin, a smaller barrel will have less total volume relative to the air chamber, so the gas pressure will remain higher for a longer period of time, but the same effect can be acheived by simply making the air chamber larger.
  • What is the optimal barrel length? - I do not know.
  • What is the optimal air chamber size? - I do not know. In receiving feedback from other people who have built aircannons for use in the 100-200 psi pressure range, it seems that an air chamber volume that is close to the total barrel volume (if they're both 2" make the lengths similar) seems to work well.
  • Will it work better with a larger diameter valve? - It should, the less restriction there is to airflow the better. At the very least, it won't work worse. A friend of mine built one with a 1" valve instead of 3/4", and performance appeared to be the same.
  • I was able to find all of the parts except the 2"to.75" reducer. The clerk at the hardware store said that 0.75" is not a normal pipe size. - For the mathematically challenged store clerk: 0.75 = 3/4.
  • The Fill Valve page says most valves are rated to 120 psi max, but you said your friend runs his aircannon at 130psi, how can that be safe? - The solenoid valve he used was rated for 150 psi, and I've received feedback from people who have found them rated to 180psi or higher. Read the manual and instructions with each valve to check for maximum operating pressure.
  • Is an aircannon legal on my paintball field? - Don't ask me, ask your field operator. They are not legal on fields insured by the National Paintball Association (one of the larger paintball insurers), I do not know the rules set up by the American Paintball League (the largest paintball insurer). Personally, if I were a field operator I wouldn't let most players use them, only those I knew who had the sound judgement to use them wisely. Much the same as my feelings about full auto paintguns.
  • The valves I saw were listed for AC use, where can I get a DC valve? - Solenoids are normally triggered from alternating current, because it is much more efficient to continually hold the solenoid (like when sprinklers run for 20 minutes). However they also work just fine on direct current. An electrical engineering student once sent me a long e-mail explaining the principles of colapsing magnetic fields generated by AC current, and went on to use that to "prove" that DC current would not work to operate a solenoid. Well my friend, it was an interesting lecture, but my aircannon works just fine on DC, and has for years. Theory and conjecture are very valuable, but they can fall flat on their face in light of real world evidence. Perhaps I shouldn't have changed majors from EE to broadcasting after all. Ever seen a car with automatic door locks? Those solenoids are operated on the car's DC current too.
  • How many shots do you get per charge of the air chamber?" - One. Really though in a paintball game, there's rarely a chance to shoot a whole group of people more than once in a game, so it's no big deal.
  • Why are you so cool? - It's only a facade, I'm really a computer/paintball geek, but people see my wife with me and think "Hey, he must be cool to hang out with her."
  • How long does it take you to charge the air chamber with a hand pump? - A couple of minutes. Refilling with regulated CO2 or a 12v air compressor is easier in the staging area. A Self-filling aircannon using a paintball pneumatics regulator like the Palmer's Rock regulator is pretty easy to do, but very hazardous (risk of overfilling) unless you have some sort of pressure releif valve to keep you from overfilling. You should NEVER fill from a pressure source higher than the rating of the weakest component in the aircannon (e.i. Unregulated CO2). I have been told third hand that the CO2 powered version of the Air Power cannon used simply a valve and pressure gauge. The user opened the valve, and closed it when 100 psi was reached. I have been told (this is unconfirmed, but is definitely physically possible) that one person had a valve that leaked very slightly, so the pressure in the air chamber kept rising until it finally ruptured taking most of it's owner's arm with it. The unconfirmed story says that's why they went off the market.
  • Can I charge it with 12 gram CO2 cartridges? The small volume of a 12g cartridge does act as a limiting factor to prevent overfill, but I've never done the math to know how much pressure one 12 gram would create in my air chamber. Bret Gollihew makes the SRP-LAW aircannons which are available from a number of paintball stores and fields including Waynes World and Brazoo's. The SRP-LAW is very compact, and uses a ball valve design. A single 12g cartridge charges a small metal air chamber that is dumped into the barrel when firing. I blended the idea of a regulator charged air chamber, and a ball valve when I built the Dethray 2000.
  • Do you have blueprints for the Dethray 2000? No.
  • Was the Air Power company that made the Sabot Cannon the same Air Power that made the Vector paintgun? - No.
  • How did you make a cartridge for the paintballs? - Hello, McFly - read the homepage - click the cartridge link.
  • Where did you buy your valve? - Fresno Ag Hardware.
  • Where can I buy a valve? - Large harware stores that sell home irrigation supplies, if you live in a part of the country where lawn sprinklers are common. If not, they can be ordered from <a href="http://www.amazon.com/gp/product/B0039PQGWE/ref=as_li_tf_tl?ie=UTF8&tag=corincom-20&linkCode=as2&camp=1789&creative=9325&creativeASIN=B0039PQGWE">Amazon</a> and similar vendors.
  • How much do the valves cost? - I've seen them priced from $8 to $18.
  • How much did all of the parts cost? - The electronics parts I pulled out of my scrap box (the battery box and switch box were switch boxes for a printer selector in a computer lab at Fresno State University in their former life) so I don't really know. I spent around $40 on the valve and pipe parts.
  • I've looked at all the local hardware stores and no one has a sprinkler valve like the one you show. All the ones I have seen have little glass vials in them. - Are you sure you're looking for a lawn sprinkler valve, not a fire supression sprinkler valve?
  • Where did you get the fill valve? - A friend of mine bought it at a little auto parts store in Lindsay, CA. Most tire fill valves are rubber and just hold into the rim with air pressure. This is a chromed valve stem, and it bolts in with its own seals, like this Gorilla Automotive valve.
  • What make and model solenoid valve did you use? - It was a Rainbird valve, I don't know the model number, I threw away the packaging when I made it in 1989. I've not seen an automatic sprinkler valve in the hardware store that wouldn't work well.
  • Can you send me step by step assembly instructions? - No. First because I have never written them.  And second, because an Aircannon is a very simple device to construct and operate. I am most concerned that a person who lacks the cognative ability to understand it would lack the common sense to use an aircannon without injuring themselves or someone else.
  • Are air cannon legal in my area? - As I have not researched their legality in every community in the world, I'm probably not the best person to ask. If you're in a city, ask your local police, or in a county, your local sheriff. Be sure to explain that it uses no fire or explosion, and does not use a fixed charge (Under California law anything with a bore over .6 inches firing a fixed charge - like bullet complete with casing and powder - is a dangerous or destructive device and illegal). There is a high likelyhood that the law enforcement officer may arbitrarily say no, because he/she doesn't really know and wants to err on the side of safety. If they say no, ask them for references on what law/statute/ordinance prohibits it, and read that text carefully. If they don't know what law/statute/ordinance it would violate, ask them if they're really sure is wouldn't be legal. Remember though in all 50 states, using it to vandalize someone's property, assault another person, or create a hazard (like by firing it from a moving vehicle) will be illegal.
  • Can you send me a diagram and instructions on the backpack aircannon? - No. I do not have them.
  • My militia unit would like to build some air cannons to defend our compound from the FBI, do you have plans for anti-personel or armor peircing shells that could be launched with them? - Go away, you scare me. I designed and built my air cannon as a sports/entertainment device, not a weapon.
  • What is the most unusual practical aplication you have heard of your design being used for so far? - A HAM Radio operator e-mailed telling me he was using one to launch string into trees to raise an antena for HAM radio competitions where you are timed for how fast you can set-up an field radio and make a certain number of contacts. Many HAM operators are big into preparing for civil emergency, and have played important roles in relief efforts during many natural disasters. I've also received a number of e-mails from theatre techs who have built to launch confetti for everything from stage plays and a pirate ship float to the half-time show at the Orange Bowl.
  • If I send you some money, will you send me all of the parts I need? - No, but I have provided links to where you can buy parts online in the <a href="fittings.html">fittings section.</a>
  • How much would you charge me to build an air cannon? - $2 million US. That way I'd have money set aside in case of a liability lawsuit.
  • What software did you use to make the 3D Illustrations? - Lightwave 3D - the professional 3D animation software that's cheaper than a car - Unless it's a really crappy car. Allen Hastings and Stuart Fergusun are two of the coolest people on the planet. Their affordable software, and the unparelleled product support Stuart used to provide in the Lighwave mailing list helped make it possible for me to make a living self-employed.  Lightwave was bundled with the original Video Toaster, and now with the VideoToasterNT.
  • What was the most offensive e-mail you've recieved about the aircannon page? - I would have to say it was this gem from Mark

  • Subject:Smart A--
    If you spent as much time trying to explain something as you did trying to sound smart, you wouldn't come across like
    such an a--hole. You said to look at the diagram for the length of pipe for your air cannon. I looked at the diagram and I
    see no measurements listed. When someone builds one of these from your sorry instructions and they get hurt I hope
    they sue your smart a-- and you live with the knowledge that you could have helped them not to make a mistake....
    Try making a page that offers good safe information instead of one that makes people feel like a dumb a-- because they need a little
    more info. You and your page suck spuds.
    Hmm, I write a web page about my aircannon, because I'm tired of answering the same questions over and over in rec.sport.paintball, and it generates more questions.  One of the most common questions is "What length of pipe did you use?"  I'm not sure why that question was common, since the answer is on the web site in plain English.  I figured people just weren't clicking on the pipe diagram page, so I put that question and answer in the FAQs, again so I wouldn't have to answer the same question over and over (the point of putting it on the web).  Now, according to Mark, I "suck spuds".  Some people just don't get it.