Grant Erwin wrote:
Old Volkswagen engine blocks were made from magnesium. I have a friend
who has the dubious honor of being the only guy in history to ever get
banned from Alta Lake State Park in eastern Washington. His misdemeanor?
He brought a stripped VW block and put it in his campfire to see what
would happen. When it ignited, it made an eyeball-searing blast of light
that must have been most dramatic to judge by the behavior of the local
law enforcement officials. Yet it was done legally - after all, everyone
makes campfires and fireplaces are for flammable substances. He didn't
go to jail but he did get thrown out of that park and banned for life. :-)
Umm, yes, I saw a VW Microbus on fire some years ago, and after
parking a safe distance away, I walked back, arriving about the
same time as a bunch of fire engines. The firemen stood around,
watching it burn, and getting out a few hoses. Somebody asked
me why they weren't putting it out, and I told them the engine
block or transmission (I didn't know which) was magnesium, and
it can cause an "explosion" if you put water on burning
magnesium. Eventually, another department rolled up with a 5
gallon bromine foam canister, and one guy sprayed the foam on
the engine while the other guys kept him doused. When the foam
ran out, the other two guys hit the engine full blast with two
booster hoses. There was a HUGE blue-white flash, totally
amazing, and a bunch of glowing metal crashed to the ground,
leaving big craters in the pavement. Once the magnesium was
cooled off, the rest of the fire was put out in about 3 seconds.

I'm not sure what would have happened if they sprayed water on
the engine without the foam first, but it probably would have
been even more spectacular.

A friend of mine tried this with a little powdered magnesium in
his dorm room a longer time ago, and then splashed some water on
it. he ended up paying for new floor tile in the room.

Jon