We’ve all probably seen videos of giant industrial shredders eating engine blocks for lunch and spitting out a stream of fine metal chips. The raw power of these metal-munching monsters is truly terrifying, and they seem to be the inspiration for SHREDII, the tiny plastic shredder for recycling plastic waste at home.
The fact that the SHREDII is not so large does not make it less dangerous, at least for things smaller and softer than the engine block, such as the fingers. The core of the shredder is a hexagonal axle that carries multiple laser-cut, sheet steel blades. Rotating blades are hollow along the axis so that they nest in the bed of stationary blades; Normal axle rotation results in the shearing and cutting process required to cut plastic pieces.
In one version of the shredder, each blade had two hooked teeth and the whole cutting head was made of relatively thick steel. When a NEMA 34 is powered by a stepper – an oddly preferred choice but they can get it fast – with a 50: 1 planetary gearbox, Schrader must have done business. The pieces were a little more fragmented, though, so the version used thinner steel for the two blades and gave the rotating blades more teeth. The difference was enough – many fine pieces that are suitable for INJEKTO, their homebrew direct-feed injection molding machine.
There is much to be said for closing the plastic loop used in desktop manufacturing processes, and the team at SHREDII and INJEKTO have stood up to help home gamers recycle plastic waste effectively. And while it’s all well and good, let’s face it – it’s not uncommon to see such a shredder being chewed on a plastic sheet.
Thanks for the tip, [Alen]!