For the manufacture in the home of products fromPrecious metals need a melting furnace. Of course, you do not need an industrial installation that allows you to process several kilograms of gold, because you are not going to manufacture jewelry for sale.
Quite enough for a small oven, able to satisfy your modest creative requests.
What requirements must the homeA furnace for melting metals? It should have a wide range of heating, be compact and convenient to use. If you have the skills and abilities, you can assemble a plant in which the carbon graphite powder is poured between two electrodes of the same composition, to which voltage 25-50 V is applied. A sufficiently powerful transformer (such as a welding one) will also be needed.
Due to the corresponding resistance inGraphite powder forms a gradual intense heating. In such an electric furnace, the temperature can reach up to 3000oC, this mode allows to melt in small portions almost all metals, including gold.
The time for heating the furnace is in the range from3 to 5 minutes. This allows you to control the process of melting metal, including turning off the transformer. Since the metal melts in small portions, it does not spread out inside the oven and keeps the shape well enough.
The electric melting furnace is made ofAvailable materials: tile or cement tiles, graphite and mica. The dimensions of the furnace can be different and depend on the power of the network and the output voltage of the transformer. The higher this voltage, the greater the distance between the electrodes. Thus, the use of a welding transformer, which gives out up to 60 V, requires a distance between electrodes of about 200 mm. In this volume of the furnace, several tens of grams of gold or silver can be melted.
As electrodes brushes from powerfulThe electric motor. If these brushes can not be used, they can be cut from a piece of graphite. In the electrode, consider two holes with a diameter of 5 mm, into which a stranded copper wire is inserted. On the inner side of the electrodes, make a notch to improve the contact with the graphite powder.
Mica serves as the lining layer of the wallsFurnace. It is a good heat insulator. External walls reinforce with cement slab 10 mm thick. Stand for the oven will serve as a normal brick, laid on an enameled metal pallet with beads.
Carbon graphite powder can be obtained by treating the filaments that have served their rods. During the melting process, the powder will gradually burn out and require replacement.
The assembled furnace is connected to a transformerThick copper wires with external insulation to avoid short circuits. Preheat the prepared oven so that in the future it will work without soot and burnt.
Smelting occurs as follows: first, using a spatula in the middle of the furnace, make a hole in powder, put the first portion of metal in it and dig in. If used goldTh scrap of different sizes, then first place the largest piece, and as it melts, add small parts.
To make sure that the metal has melted,Just rock the stove. The surface of the powder will then shake. After melting, the metal is turned over and melted again. So repeat until the workpiece does not take a spherical shape (this indicates the quality of the melt).
After melting, the metal workpieces are to be forged. The product must be taped on the anvil with a small hammer.