These things are a lot of fun, I shoot taters, tennis balls, golf balls etc..I use ether for propellant....if you have never made one, you should Required Materials: 2 foot section of 4 inch PVC pipe 4 foot section of 2 inch PVC pipe 4 inch to 2 inch PVC pipe reducer 4 inch sewer cleanout plug Electric barbeque starter Screws, epoxy, hair spray and a big bag of potatoes that are larger than 2 inches in diameter Construction: Sharpen the end of the two inch diameter pipe, it should cleanly core a potato when inserted. At about 4 inches from the other end, insert 3 or 4 screws in a way that will prevent the potato from falling into the combustion chamber. Use the epoxy and glue the pipes to the reducer, and the sewer pipe end on the back of the gun. Drill two holes across from one another, and install the electric barbeque lighter, following the directions that come with your igniter. Note: If possible try to buy the two-wire push button switch, rather than a single wire model, as it is easier to install. Use a nail or bolt to serve as the ground contact. Test the distance before you glue things into place, to make sure you consistently get a good spark. Operation: Insert a potato into the gun barrel. Using a broom handle or similar item, push the potato down down the barrel to the screws at the bottom. Unscrew the plug at the back, and give the chamber a short burst of hair spray. Note: The amount of fuel is very critical! Too much and it will not ignite, and not enough and you will get a poor shot. Aim carefully and ignite your potato gun. Once you are satisfied with the potato gun operation, try some target shooting, long distance records, and maybe bazooka-style shoulder launches.