For most people, the concept of "foundry" is strongly associated with huge melting furnaces, rumble, smoke and streams of red-hot metal pouring like a river of fire. But in fact, you can cast a small piece of tin, lead, brass or aluminum at home.
The casting process itself is very simple. The main thing in foundry is to make a casting mold. It is created in a mold box called a flask. Its dimensions should exceed the dimensions of the cast part by approximately 1.5 times.
The flask consists of an upper and a lower part. The upper part is a frame with 2-3 crossbars in the central part, and the lower one is a box with a bottom. The investment ring must be strong. To do this, fasten the upper and lower parts together with clamps.
Fill the inside of the box with molding earth - a mixture of clean fine sand, clay and coal dust. As a rule, the model for making a mold is a similar part or a model made of wood or other material.
During the molding process, fill the lower part of the investment ring with molding earth, which then needs to be lightly tamped. Sprinkle the model itself with powdered graphite or talc and press it halfway into the ground so that it can then be removed.
Sprinkle graphite over the ground in the box, then install the top and align the clips. An important part of the casting mold is the sprue (conical plug), which is inserted into the irrelevant part of the future part. Metal will be poured through it.
Then fill the investment ring with molding earth, compact it tightly and carefully remove the plug under the sprue. Then use a sharp object to separate the upper and lower parts of the investment ring until completely dry. A shape should be formed between them, corresponding to the shape of the future part.
According to another technology, a model of a product is made of wax or paraffin, then covered with a heat-resistant, rapidly solidifying mass. After drying, the model heats up, wax or paraffin flows out through the hole, and a mold is obtained for pouring molten metal.