While roaming countless construction sites in my Arizona childhood, I fetishized found objects of industry as boy-war trophies. Pop rivets were katanas, nailgun cartridge belts were bullets. I dreamt of being able to make anything out of metal. With the furnace I completed this year per the instructions of the estimable engineer Colin Peck, I can finally do that—though casting technicalities have proven almost as vexing as furnace building.
This furnace is the most olivegreen thing I’ve built: it’s made of an industrial shop vac’s stainless shell welded onto a chassis of gnarly angle iron from a curbside in Bushwick, Brooklyn. The lining that supports the 100 pounds of refractory cement inside is fake wood-grain aluminum siding from an above ground pool, riveted together. The frame holding the lid is steel salvaged from a fun-park carousel interpreted in a Queens sculpture park, attached to a hollow steel stem that was some piece of crap my neighbor gave me when they feebly encouraged my eccentricities. The carburetor is aircraft-grade stainless steel, maybe a rejected Boeing or Sikorsky part, from a Brooklyn machining plant, regulated by a valve I machined from a cast-off block of aluminum from another Brooklyn machining plant. A vacuum cleaner motor brought from Chicago by a friend (which lived, in the vacuum, in my basement for 3 years) provides the blast for the furnace.
Every step of this process was taken blind into uncharted territory, which is excruciating because I want to make art, not tools. Colin’s plans require that you do what you can with materials you can find, which results in so many grey areas I’d have torn all my hair out if I had any. Yet though I’m a terrible and impatient engineer, this thing works astonishingly well.
Every fuel element is waste. A local carpet dealer that takes pallet shipments every week gives me the wood I use to kindle it. I ignite a small fire inside it, which the blower cyclones into a high heat, then turn on the oil valve. (The oil, as I’ve mentioned in another post, is from a pizzeria and a transmission shop.) It flows towards Colin’s ingeniously simple carburetor where it is vaporized into the woodfire-heated concrete interior where, the temperature being correct, it combusts and the REAL burning starts. 1.5″ of industrial refractory cement stores the accumulating heat—I’ve seen it glow red. The furnace handily reaches the 1400 degrees F. needed to melt aluminum, and it’s actually quite safe with no potential of explosion or even fire. Oil must be a fine mist injected into very hot flaming air to burn at all.
My last burn was supposed to produce many sculptures and pieces of jewelry, but due largely to a crucible failure I was unable to pour anything but the smallest bits, which had their own problems. I had never charged the stainless pot with more than 10 lbs of aluminum, and when the 15 lbs melted it ate through the bottom of the crucible. Three pinholes dribbled aluminum steadily onto the floor of my furnace, which I noticed only when I lifted it. When the resultant mess cooled I saved it as an object lesson in heat: have you ever seen a melted brick encased in aluminum?
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