At a guess, it was probably originally an abrasive cutoff wheel tool, with a removable shield to get the disk on and off, and he wanted to try using it with a circular saw blade but couldn't fit the shield back on. Still epic fail, but with a plausible-if-in-a-hurry path to trying it anyway.

- CD

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Science isn't a what, it's a how. You can study anything with SCIENCE! It's a method of observing phenomena and recording observations in a regularized way that allows you to, after poking X with a stick enough times, predict how X will twitch. If you can't get X to twitch or can't see the twitches, then either your stick or your magnifying glass are insufficiently advanced, and crying "magic" is what you do when you don't want to admit it.
"If Carbon's the slut of organic chemistry, then Fluorine is the serial murder-rapist" - Black Aeronaut