Bird Cannon Restoration

This restoration is on a ZON bird cannon made by the B. M. Lawrence Co. of San Francisco, CA, USA in the 1950s. This tool is also called an automatic scarecrow, carbide cannon, bird scarer, or orchard cannon and cost 60 USD in 1955 which is about 750 USD today. You can view the original patent here: The cannon works by the user mixing calcium carbide and water to create acetylene gas. Once the gas builds up to a certain amount, it is emptied into the explosion chamber and a flint is struck, igniting the gas and creating an extremely loud sound in hopes of scaring away birds and apparently human ears. This is the most dangerous tool I have restored thus far. The risk of creating shrapnel was present and real during every restoration decision. The main rubber diaphragm was completely rotten and needed replacing, but if I did not find rubber with equivalent thickness, strength, elasticity, and resistance to acetylene, I c