The Deer Spring Fountain Project
A friend of mine and I were approached by the Saratoga Springs Department of Public Works to see if we could recreate, in aluminum, the lion heads which were essentially destroyed on the deer spring fountain in Congress Park, Saratoga Springs, NY. The DPW's artist, Phillip Steffen, duplicated the lion heads for us, which we then used to create a silicone mold, we cast six of them in wax, attached pouring sprues and invested them in a mixture of Plaster of Paris and silica sand. These were burned out and pre-heated to around 1,000° F in a red brick wood fired kiln which was built hastily on site for this purpose.
The aluminum was melted in a crude coal fired foundry (we used a brake disc as the lid and a vacuum cleaner as the air source), then poured into the pre-heated molds. Of the six lion heads, the best three were chosen and welded to the finished fountain.
Investment mold for the lion head made from plaster of paris and silica sand freshly filled with molten aluminum
Fresh from the mold
Cleaned but sprue still attached
Finished, welded in place and painted Deer Spring Fountain
The Mini Arc Furnace is Born!
From this crude beginning, I developed a love of casting metal. There was something about the ease of simply pouring a substance into a mold, while when cool, the material is hard and very difficult to work with. The success of the project above fueled a desire to cast in the most demanding of materials... steel. Iron can be cast relatively easily. While the approach to it cannot be haphazard, it doesn't require the attention to chemistry that cannot be neglected when melting and casting steels as the window of their carbon content is so crucial.
The arc furnace concept was what I settled on. Mainly this was due to the face that, at the time, I wasn't confident that I could construct an appreciably robust induction furnace that wouldn't cook itself in a few short moments. For another, I had some welding experience and knew that an electric arc of some appreciable wattage, when the heat is retained could easily melt even the most refractory metals on the planet.
My first few miniature arc furnaces were little better than poor attempts at using an arc welder to met steel in a clay crucible. on the procedeeding pages are some images of the circuitry and resultant hopeless attempts to get an arc to melt an appreciable amount of metal before tripping a breaker or incinerating some portion of the crudely constructed apparatus.
Image of attempt no. 2 using a DC furnace design. This was a manually operated furnace using a threaded rod on an armature to start and adjust the arc length. Read more about it on the Mark II page