Any metal will work if you make dowels to line them up like two peace molds for plastics. The two halves need to match up with each other fitting flat on each other and not able to see threw them even 1/4 in straping will work. Aluminum is the easyest to work with. Useing althread rod drill the two sides the same size as the threads. thread the one side and drill out the other side so the allthread slides threw. Then use nuts to hold the two halfs together. Just drill a hole the size you want. You might have all you need already in your shop for this project! Metal peace to cut in half, two bolts if you dont have allthread, four nuts, drill bit or two. good luck and have fun.