THE CRAFT OF FIRE

Who knew that our own young city of Toronto played a part in the ancient technique of lost-wax casting? As I was researching the history of this technique, I discovered this : "It  was in 1934 that a Danish engineer, Thoger Gronborg Jungersen, working with a firm of manufacturing jewellers in Toronto, devised the flexible rubber mould from which any required number of identical wax patterns can be obtained. This made  it  possible to produce substantial quantities  of  small castings possessing all the fine detail of the original master pattern." Who was this T.G. Jungersen, and did he really invent the idea of using a rubber mould to produce multiple wax copies - a process we all follow today? In 1938, he received a patent for the following invention: "A method of casting articles of jewelry of intricate design consisting in first producing a model of the article to be cast, then forming about said model a primary mould of a plastic material which wi...

We've entered the Age of Metals! Back in September, we did our first backyard pewter casting, using the lost-wax process with plaster molds. It took us while to source the metal ingredients to mix up the pewter ourselves, but finally we found them and then followed this recipe, by weight: 70% tin    (melting point 232° C) 20% zinc  (melting point 420° C) 10% lead  (melting point 328° C) Jorge and I mixed up the metals in a big pot. You first melt the one with the highest melting point, and then the others in descending order. 1 lb of zinc 1/2 pound of lead shot after adding the tin and mixing, the oxidation produced these amazing colours We also heated up our plaster molds to about 235° C, in the kitchen oven, so the metal would flow better and to reduce any possible thermal shock. And then we poured:  Next, after a number of hours of cool-down, comes that truly magical moment of breaking the mould and ...