Sprues and Slurry

March 09, 2021

This week we worked on breaking up iron, creating sprue systems for the wax sculptures, and breaking up condensed and purified coal (aka coke). Students continued to break down the CSS iron furnace into smaller pieces, and measure out 25-pound portions of iron for the Iron Pour. Sprue systems are systems of wax that hold all of our sculptures. We create a cone-shaped base and a long piece of wax as the base of the sprue system. Then we use the hot tools to melt each piece to the sprue. Then we use smaller pieces of wax to act as vents for each sculpture. This will ensure that when we pour the iron into these systems, there will be no air bubbles or trapped air. After we connect all of the wax, we dip the sculptures into a mixture called “slurry.” After six or seven dips, with breaks in-between, the system will harden and become stable. Later on, we will put each mold into a flash kiln. The flash kiln will heat up and melt the wax out of the molds quickly. Then the sculptures encased in this ceramic structure and will be ready for pouring iron.