On Wed, 10 Oct 2007 23:39:14 -0500, Jon Elson
wrote:

Richard J Kinch wrote:
Joe AutoDrill writes:


If I buy magnesium from somewhere (McMaster doesn't seem to carry it
or I'm semi-blind), can I do the same thing?


Sure. I've done it scraping the tubular handle of a lightweight magnesium
landscaping rake. Odd chunks are on eBay all the time. I have 1/8"
magnesium welding rods from aerospace surplus.

I'm skeptical of the engine block tales. Large pieces don't ignite since
they have little surface area. The 1/8" welding rods self-extinguish if
you light them. They'll only maintain burning if you hammer them into a
flatter ribbon shape. And weren't the engine blocks an Mg-Al alloy?

Well, it takes a good fire to get it started. A small
electrical spark can't possibly do it, but a welding arc will.
VW Microbusses had the gas tank RIGHT NEXT to the engine,
between the firewall and the cooling air plenum. A little,
crumbly rubber hose to the carburetor. If that hose breaks, it
sprays gasoline by gravity feed right onto the exhaust manifold.
Pour gas on the manifold, then vapor goes into the generator
brushes, and FOOM! Now, you've got the engine sitting a foot
over a giant gas fire, as the tank empties itself into a great
big pool of burning gas. That will get the crankcase lit in
about 4-5 minutes, if there's enough gas to keep it burning that
long.

I definitely saw one do this once, and it was sputtering white
hot bits of magnesium onto the pavement before the fire dept
foamed it, so no question the crankcase had gotten lit. Then
they hit it with water right after the foam, and it was like the
4th of july ground display making the flag in burning sparks or
something.

Jon
Several years ago I worked at a place where we once had a lot of mag
chips to get rid of and the scrap dealer wouldn't take them. I
suggested burning some. We filled a cardboard box full and set it on a
5 gallon bucket full of water. The chips were burning for several
minutes and had not yet melted through. The shop skeptic groused that
nothing would happen, that I was full of ****. Just then the molten
burning mag fell into the bucket. The skeptic says" MY EYES!". Flames
and white ash abound. We found another way to get rid of the rest.
ERS