||[Mar. 19th, 2003|11:43 pm]
Well, proved a couple of things today.|
First, a fresh 80 grit belt will grind through gloves and into your finger faster than you can react. Shouldn't scar up, at least, only flayed me a bit. Abrasions are some of the most painful wounds, though.
2ndly, despite what I read on the net, a clay flowerpot with the holes plugged up with furnance cement will not hold up to even moderate temoeratures. As I doubted this anyway, no harm done, just some wasted gas and iron ore. Oh, and I'm starting to doubt the "carbothermic smelting process" for iron as suggested by Dr. J. E. Rehder, though it is also quite likely that my methodology is at fault. Carbothermic smelting is smelting (reducing ore to metal) in a crucible packed with a mixture of ore, flux, and charcoal. While it is likely my ratio was off, and the crucible developed cracks shortly after preheating, and failed after 1.5 hours, no iron was recovered from the remains, only some slag and what looked like unreduced ore. I used a ratio of 10% charcoal, 85% ore, and 5% flux (half iron silicate (slag) half crushed limestone. Still, it was only an experiment, not a real attemp, so no harm done. I needed to kill those propane tanks anyway, they were both so low that they kept freezing up.
I do plan on making a small bloomery, as I want some examples to haul around with me for when I teach classes on early metalurgy or knifemaking. Rehder's book, The Mastery and Uses of Fire, has a good description of such a bloomery, along with operating instructions and an ingredient list. Shouldn't take too long to put together, I'll start scrounging materials tomorrow. I'd like to get the refractory rammed up before I head out to Lunacon this weekend.