Since a combustion cannon operates on the principles of combustion, the cannon requires what is called a fuel to air ratio. Because of this requirement for a proper amount of fuel, sometimes a quick burst of hairspray will result in a misfire or simply have poor performance. By building this simple tool for combustion cannons, the amount of fuel entering the cannon will be controlled, optimizing performance. So get out there in your shop after you watch this video and make your own propane meter for your combustion spud cannon. This is all you need to watch to see how to build the launcher.