Rapidair MaxLine 3/4" Pipe Straightener Pulley

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Setting up a compressed air system in my shop using the 3/4" Rapidair MaxLine kit requires a cost-effective way to straighten the pipe for installation. I designed this pulley to build a tool that I could use to pull the pipe through and uncoil it smoothly. The pulley features a 3/8" pivot hole, with the center of the pulley to the center where the pipe rides measuring 1.5". To minimize friction while providing support, I added a rib on the bottom of the pulley. To build this tool, you will need the following hardware: * 7 - 3/8" x 3" Bolts * 14 - 3/8" Washers * 7 - Nyloc Nuts (optional) * 1 - 2" x 10" x 3'+ piece of pine lumber * Powdered Graphite I marked out a 3" grid on the 2X10 and drilled pilot holes with a 1/8" bit, followed by final holes with a 5/16" bit. To reduce friction, I worked graphite into the pulley hub along with the bolt and washer. Then, I screwed the bolt directly into the wood, positioning the rib side of the pulley towards the wood and tightening it just enough to confine the pulley without binding. To secure the bolts further, I added Nyloc nuts and washers on the bottom side of the board, but this may not be necessary. Finally, I mounted a 1/2" dia piece of steel pipe to the board to hold the spool of air pipe while pulling it through the pulley.