Aluminum swivel pulley cast in ABS mold

thingiverse

An ambitious attempt at a pre-assembled casting. Instructions This aluminum swivel pulley was cast directly in an ABS mold with a one-inch wheel diameter, which should easily accommodate a 1/4 inch rope. An update: An alternate swivel style was uploaded by mistake. I left that option here (pulley_alternate.stl) and added the actual version used in this project (pulley.stl). Either one can be printed if someone wants a plastic pulley, with the wheel and axle fitting perfectly into either one. Given that pre-assembled parts are commonly 3D printed, I thought it might be feasible to print a mold where the cast metal parts would already be assembled. This pulley was an elementary test case. The swivel ring is embedded directly within the pulley, such that when the mold is removed, the ring should ideally be free to pivot. So far, I've refrained from casting the wheel itself since it's highly likely I'll redesign the whole project if I ever intend to use it seriously. The pulley's wheel could probably be cast in place with a nut and bolt assembly, but that would require a specific clearance between the parts. Minimal space around the axle seems essential, causing a fundamental conflict. In theory, an integrated wheel/axle could be successfully cast if deemed worthwhile; however, using a straightforward nut-and-bolt system remains significantly easier. ,,,,,,,,, Over recent experiments, I've had to face multiple setbacks, one of which was my attempt at creating a timing pulley. I have yet to succeed in spite of over a dozen attempts. One fateful time, an incredibly impressive explosion erupted when I attempted casting the timing pulley via a different method. Aluminum had been poured at a scorching temperature while the mold spun frantically at 2000 RPM, creating a catastrophic spark. Thick smoke instantly rose to its ignition point and disappeared into flames. After witnessing this terrifying spectacle, I began contemplating abandoning my endeavors in aluminum casting entirely. Nonetheless, the jitters subsided several hours later once rational thinking reasserted itself. This intense moment turned out to be just an impromptu lesson: never grow overconfident in any skill or project.