How to make a bungee launcher and building tips

3 @ 3/4“ T connector 2 @ 3/4“ X (four connection cross joiners) 5 @ 3/4“ end caps 6 @ 3/4“ 90’s 4 @ 1“ T’s 4 @ 1“ to 3/4“ adapters 3 @ 10“ 3/4“ lengths of PVC 1 @ small can of PVC cement 2 @ 3/4“ metal pipe brackets 1 @ 3/8“ X 3“ bolt or lynch pin (unthreaded for release pin) 2 @ 1“ welded steel rings 5 feet nylon cord or shoe lace 10 feet foam pipe insulation 3 @ plastic tent stakes heavy duty 20 feet bungee or surgical tubing cheap fish scale (hang