Joe, In the oilfield we used to make hinges from short sections of pipe. We used 2 outside sectiona about 1" long, and an inside section about 1 1/2 or 2" long. Key was that we installed a bolt or rod in the pipes that had a lot of clearance - min of 1/16" this clearance was enough to vibrate and pound out accumulated rust, etc. Thanks Dennis Sent from my iPad