It's a sad, embarrassing story Deejay. I wanted a miniature flat-disk, horizontal-shaft grinder as a workshop machine, and I wanted it to be free. So I decided to attach the 3 phase angle-grinder to a frame. On one side it had a tapped hole for the lateral handle (it was a full-sized 9" angle grinder, and they always have lateral handles for reasons which become obvious the first time you pull the trigger on one and experience the gyroscopic precession as it accelerates the grinding disk). However I needed another mounting point approximately horizontally-opposite that handle. There was an unused boss on the housing in the right place, so I decided to tap it and screw in the mounting. Then a small error crept in. Naturally I was doing this without dismantling the grinder - it was a very small job. Instead of bolting the grinder down to the table of the milling machine and feeding the tapping-sized drill bit by moving the table up, I held it in position on the table of a large vertical drill. Murphy's Law was in operation: the drill bit immediately grabbed the aluminium housing of the grinder, and pulled it upward so that the drill bit penetrated the housing rather than stopping at the bottom of the boss. Phase 2 of Murphy's Law also applied: the drill bit dug well into the windings of the grinder's induction motor. My ambitions do not extend nearly so far as to try to rewind a miniaturised 3 phase induction motor, so I flipped the whole machine into the nearest skip.
