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by alnwlsn 341 days ago
This reminds me of burning scrap VW engine blocks or transmission cases. It can be done on an ordinary wood camp fire. You'll probably want to cut up the scrap into more manageable chunks rather than go for the whole thing at once. Then, toss a few into the hottest part of the fire. For about a half hour, nothing will happen. Then, the chunks will begin to melt, forming puddles onto the bed of coals, where they will ignite.

It is interesting that the pools of liquid metal burn quite slowly in the middle of the regular fire; you will only get a bright orange flame rather than the spectacle promised. Maybe only 5x as bright as a normal fire. But, if you scoop some up onto a stick (a long piece of steel angle iron is recommended) and pull it out of the fire into open air, it will burn with the brilliant white flame with which you are generally familiar.

For the finale, plunge the end of the stick into a large bucket of water, where you will observe the magnesium blob continue to burn while submerged for several seconds. Do not attempt to do this the opposite way by dumping the bucket onto the fire; an explosion will result instead. In fact, keep all moisture away from the fire in general. If you need to put the fire out for any reason, too bad.

After the fire burns itself out, the next day you might find some solidified blobs of unburnt magnesium. Be sure to remove all of these so you do not have an unexpected experience the next time you have a fire there. I have quite a nice piece where the magnesium flowed around a stick, but did not ignite.

This comment comes with the obvious disclaimer that nobody anywhere should try this for any reason, especially not the reason of fun.

3 comments

One of the more memorable experiences of my youth was watching a VW microbus burn. It had been stored over the winter and evidently the fuel line had either deteriorated or been chewed on by an animal. After idling for a few minutes it went spectacularly up in flames. The firefighters weren’t expecting magnesium and were quite surprised by the intensity of the fire and the bright white flames from the puddles of molten metal.
This is a common problem with rear-engine VWs if the fuel lines aren’t maintained. Fuel pumping through rubber hoses directly over hot exhaust is a recipe for disaster. It’s generally recommended now to replace the lines at least every ten years. You don’t see them wearing as they do so from the inside. Things can even start up after sitting for a while after driving since the exhaust is still hot and there is pressure in the lines.
On the '65 beetle we have, I always heard that the main culprit wasn't the fuel lines themselves, but the brass flange for the fuel hose being a (not great) press-fit into the zinc carburetor. And that's after the fuel pump, so if that flange comes out the loose end of the hose sprays gasoline all over the engine. It's not uncommon to tie that end of the hose on with some safety wire, just in case.
Makes sense. I'm talking mostly from the perspective of fuel injected Vanagons. Connections generally seem good; it's usually the hoses.
If only we'd known! This was decades ago, before the internet, and perhaps the word had not yet got around. I loved that Microbus.
+1! This was a relatively common thing to do at the Glamis[1] sand dunes in the 1970s-1980s. Glamis is a massive sets of sand dunes in California where bunches of people go to camp and ride offroad vehicles.

1. https://en.wikipedia.org/wiki/Glamis,_California

Wow, that seems like some absolute Mad Max shit... very cool
Wouldn’t a sufficient amount of sand (eventually) put out the fire?
Presumably, but I would assume that the sort of people prepared for intense metal fires are not the same sort of people who go starting intense metal fires.