I am amassing the materials needed to build a 12" power hacksaw. To bring the motor's speed down and increase torque I plan to use a 2"-12"-2"-12" jackshaft assembly. This should yield 60-90 strokes per minute, right where I need it. 12" pulleys are rather expensive, 2 of them are doubly so. My daughter is willing to donate her old bike for the project. Sans the rubber bits the wheels measure the required 12", have wonderfully rolly bearings, and are free. Has anyone used wheels as pulleys before? The saw will only be used for light cutting duty with regular 12" blades. Am I just being TOO cheap?