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Foosh!
How should one light a Solstice bonfire? This year, I did it with thermite (video has a naughty word 'cos I was startled). That's about 150 grammes of stoichiometric thermite made with ordinary, off-the-shelf stuff and lit with a sparkler. The molten iron, at around 2000c, spattered and burned so we didn't retrieve it, but this proof-of-concept firing means I can go ahead with the thermite lost-wax casting I've got in the project file. Yes, I'm going to be doing mjolnirs. :)
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You know all about the importance drying your mold and the dangers of metal-splash, I hope ? I've only had one incident along those lines, on a very small scale, and I wouldn't want to have another. We we doing silver casting by the lost-frog process, and we hadn't baked out the frog properly, and got a real silver fountain.
In fact, I'd worry a bit about your wax plug vapourising in a steel-throwing kind of a way. I had a google, and this chap:
http://www.theodoregray.com/PeriodicTable/Elements/026/index.html
reports success using layers of aluminium foil as a plug.
Good luck!
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"My first large batch, about a pound, burned great for about 3 seconds and then exploded, which is not something thermite is supposed to do. It turns out I should not have used a zinc penny to cover the hole in the bottom of the crucible: The boiling point of zinc is much less than the temperature reached by the reaction, so when the molten iron hit the penny, it exploded into zinc vapor. A copper penny was only slightly less explosive: Turns out you're supposed to use an aluminum disk. Using folded up layers of aluminum foil I have had no more problems with explosions. Which is not to say I'm anywhere closer than 20 feet away whenever I ignite thermite: It would be really quite stupid"
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