This beautiful video shows drill bits milling into steel plates, chipping away slowly and methodically. It's a mesmerizing look at a process that takes merely seconds at full speed. The title of the video is "Metal It Is Beautiful." It certainly is!
-via Twisted Sifter
You can see chips coming off with a purple to blue color, meaning they are reaching temperatures of over 300 C. Once upon a time, I saw an offline video showing high end machining of some high temperature metal (like some kind of Inconel). It was a material that had big problems with work hardening, where strain causes the material to harden, so if you cut too slowly with the mill it will strengthen the material in front of the cutter faster than it cuts it away, wrecking havoc on the cutter. The solution is to cut very aggressively, producing red to yellow hot chips. Online videos of similar things were not as impressive as the one I saw offline, although I haven't looked too hard recently. It is one thing one a grinder makes hot dust, but another when a cutting edge going at near highway speeds is producing large, glowing chips.