Engineers have come up with all kinds of pencil sharpeners. Shane from Stuff Made Here used his engineering expertise to see if he could come up with some new ways to achieve the sharpest point for his pencils. His six ridiculous pencil sharpeners include a 5-axis waterjet, a robot with a spinning X-acto blade, and a tiny chainsaw.
It’s possible to make circular saw blades out of paper, wood, or plastic, but the glass saw blade the Waterjet Channel made could be the worst idea yet. Sure, glass is harder than those other materials, but it’s also more fragile, and the flying shards of glass coming off a spinning disc could cause serious injury. But hey, it’s the internet, so here you go.
It’s amazing how water can be pressurized so much that it can cut through things. In this clip we spotted on the Tool Gifs subreddit, we get an up-close look at how a tightly-focused stream of water can cut incredibly precise shapes in stone. The footage does appear to have been sped up, though.
Industrial waterjets can be strong enough to slice through metal. So the idea of sticking your hand into one seems like a terrible idea. That’s why the guys at the Waterjet Channel used ballistic gel dummy hands instead of human hands to see just how horrific the carnage of 60,000 PSI of H2O would be.
With enough power to cut through glass or even metal, industrial waterjets can be incredibly impressive. In this video from WARDJet, they show how one of their computer-controlled machines can slice a spiral so precisely in a sheet of glass that the glass can be stretched out into a dome after cutting.