Here is a simple tool to help you make and break the chain Rufus thought it up the other night while we were cleaning out his litter box of all things. Well sort of.
I'm using 1"x1" angle about 5" long for the tool
here is what we got to do measure out the pins on the chain and drill either 11/64" holes or 3/16" holes and deburr both side. You don't want to poke your fingers on sharp burrs. I layed the chain on the metal and eyeballed the spacing of the holes.