What is a Carbide Cannon? As it turns out, if you take some Calcium Carbide and mix it with water, it produces lime (which settles in the water) and Acetylene gas. Acetylene gas is explosive. I’ll bet you are already thinking of how to make use of that information. Well, we gave our boys a book for Christmas called Backyard Ballistics. You are probably thinking that we are bad parents for teaching our 9 and 11 year old boys stuff like that. Your probably right. The book shows you how to make a cannon that will make a lot of noise as it generates and acetylene gas that you ignite. Here are some pictures of my cannon that I built.
carbide cannon

pvc carbide cannon

pvc carbide cannon

pvc carbide cannon

My first attempt did not fire. I think the ignition hole is too big and let the acetylene out too fast. I stuffed a little paper towel in the hole and it worked great.

This is my first successful firing of the carbide cannon: I leaned over it when it went off and nearly took out my eye. Not too smart.

So I did it a second time.