My final year project for the Mechanical Engineering Technology program at Confederation College, this project was designed to render plastic into smaller pellets that could then be recycled into 3D printed filament. I got the idea from collaborating with a friend of one of my teachers who 3d printed often but often found there was a lot of waste left from the printing, as once you printed something, there was no good way in Thunder Bay to recycle the material. This was something that was echoed by the makerspaces at the College running 3D printers who had mentioned that having a desktop plastic shredder could be really useful for breaking down all of the waste material and be a good first step towards a better alternative.
My research started with other shredding devices on the market and I was able to find a few websites which gave a good breakdown of how their shredders worked and the components used in them. I designed the system to be dual-axle to better crush and break down material, and I added hooks to the ends of the blades to help draw material in. The initial plan was to have two stages to the shredder, the first stage having thicker blades to initially break down material, and the second stage to shred into smaller pellets. This turned out to be much more challenging than I thought it would be, and so I stuck to a single stage for the design. I initially also wanted to use a separate motor to run the system, but ran out of time, and so opted to make a version which relied on power from an impact gun geared down through a reducer. This worked well and I was able to successfully shred plastic.
The majority of the machine was cut from 1/8â and 0.200â steel sheet metal using a CNC plasma cutter. The blades were separated by spacers and assembled on steel shafts and mounted onto bearings inside of an aluminum housing. The whole assembled was then welded down to a piece of steel sheet metal to prevent it from moving during the processing of material.
Skills Used
| Machining | CNC |
| CAD | 3D Printing |