How to Make a Cast for an Iron Pour
- 1). Make your mold frame. Use a wooden box that is larger than the object you would like to cast. Hammer off the bottom of the box so you have a wooden frame. You can also screw together a few pieces of scrap wood to make a wooden frame. Make sure is is not only slightly larger than your object, but slightly taller.
- 2). Lay your object on a clean, flat surface you can use as a work area with the flat bottom facing down. Place the wooden frame around the object. Shake a light coating of parting dust on the object. Make sure to get the parting dust into every crevice. This will prevent the sand cast from sticking to the object.
- 3). Mix a fine-grit silica sand with water in a large container. Fine-grit sands will cast more detail in the iron than coarser grits. Add a ratio of about 4 parts sand with 1 part water. Use your hands to mix the sand until it is evenly moist.
- 4). Hold a screen over the object and place handfuls of the moist sand on top of it. Sift the sand through the screen to remove any lumps and shake into the wooden frame. Add sand until it spills over the side of the frame. Use a wooden block to pack the sand in so all of the crevices of the object are filled.
- 5). Flip the frame over carefully so you do not disturb the sand. Glue a small piece of wood to the center of the flat side of your object and let it dry. Pull lightly on the wood to remove the object from the sand. The object will leave a negative imprint in the sand.
- 6). Hold a lit blowtorch next to the sand to dry it out, concentrating on the imprint of the object. Do not let the sand turn black.
- 7). Pour molten iron into the imprint slowly until it fills the entire imprint. Let the iron cool for about 10 minutes and pour cool water onto the sand to remove the mold. Wipe the extra sand off with a cloth when the iron is entirely cool.
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