Cross cut paper shredder gear

thingiverse

This is a replacement drive gear for the gearbox of a domestic cross-cut paper shredder. The original gear, made from plastic, is prone to wear or jams if it gets stuck (it's driven by a metal gear on the motor). The new gear features 47 helical teeth at a 28-degree angle and is powered by a mains-driven electric motor. A smaller, 10-tooth metric reduction gear drives another plastic gear in the gearbox, which then powers the shredder rollers. I printed this replacement gear using PLA and it's holding up surprisingly well so far, avoiding the need to toss a £30 shredder in the trash. It's possible that the new gear may wear out faster than the original, but it's easy to reprint and replace if needed - just be sure to apply grease to all the teeth before use! I recommend using a high resolution setting to achieve a smooth finish on the helical gear faces. To get this right, try using 0.12mm layer height with a 0.4mm nozzle.