Metalcasting

From Fozzee.net

Since I first read about "backyard metalcasting" a few years back, I've wanted to try it for myself.

Stock

Presently, I have 20 or 30 pounds of random aluminum saved, including hard drive bodies, heat sinks, and other scrap. Once I have a furnace up and running, I'll pay more more attention to collecting aluminum scrap just as soon as I have my current scrap cast off into ingots for easy storage.

Furnace

I've already manufactured a basic furnace body, with an internal bore of approximately 6", and an interior volume of about 1 gallon. It's a bit unconventional in design, in that the top has some depth to it, instead of being just a lid. This was as much a necessity of my body choice (two popcorn tins) as an actual design consideration. I think it'll be fine, though I have noticed some leakage between the sections in initial preheat tests.

Speaking of preheat, I'm fairly impressed with the performance of my unorthodox refractory mix. I'm using 50% Portland cement and 50% perlite (by volume). The water required is quite a bit more than the 1 liter per 20 pounds of cement that the bag specifies, mostly due to the absorption of the highly porous perlite.

If I had to do it over, I'd probably use a cement with less (or at least smaller) inclusions. It'd make the thinner parts of the furnace stronger. Portland cement is (Technically) not rated for surfaces thinner than 2 inches.

Burner

I'm currently building a waste-oil fired, forced air burner. The blower is a double-fan model salvaged out of an over-the-range microwave (Donated by Blake). The fuel will be primarily used motor oil, though said oil may need to be cut with kerosene or diesel fuel to make it flow nicely.

Of the whole of the metalcasting project, making the fire is, to me, the most problematic part.