A moulding material for casting molten metal. It requires no baking or pre-treatment of any kind. It is a very fine, plasticised, oil bonded sand. The oil prevents oxidation and gives the casting a shiny finish. It takes up very fine detail and the casting requires no surface finishing.
Application; Get two steel boxes, open both ends, accurately located one above the other. Fill one with Thermould. Press the model into the joint face. Powder the surface with talc. Place the other box over it, fill it with Thermould and press it tight. Make a runner and filling funnel. Remove the model, replace the box and cast the metal. When it has frozen, open the box and remove the casting. Discard the burnt Thermould adhering to it and cut off the runner. The whole job can be done in about 10 minutes.
The unburned Thermould can be reused. Ideally it should be remixed in a muller mixer, which has a heavy wheel pressing on the material. Long mixing in a planetary (bakery type) mixer also works. Thermould belongs to a generic group of oil bonded sands called “Petrobond” sand. If the Thermould starts to loose its cohesion, add a bit of Enerflex oil or smokeless two stroke oil. Apart from plasticity, Thermould also exhibits some compressibility. This property makes it quite forgiving towards imperfect compaction.
Use it to cast aluminium, tin, brass, bronze, copper, zinc, magnesium, silver and gold.