For production in house conditions of products from precious metals the melting furnace is necessary. Certainly, you will not need the plant allowing to process several kilograms of gold, you are not going to be engaged in production of jewelry for sale. Quite there will be enough small furnace capable to satisfy your modest creative inquiries.
Instruction
1. What requirements does the home furnace for melting of metals have to meet? It has to have the wide range of heating, to be compact and convenient in use. With skills and abilities you can collect installation in which carbon and graphite powder is filled up between two same electrodes on structure to which voltage of 25-50 V is brought. Also rather powerful transformer is required (like welding).
2. At the expense of the corresponding resistance in graphite powder the gradual intensive heating is formed. In such electric furnace temperature can reach 3000 wasps, this mode allows to melt in the small portions practically all metals, including gold.
3. Time of a warming up of the furnace occurs in the range from the 3rd up to 5 minutes. It allows to operate metal melting process, switching on and off the transformer. As metal melts in the small portions, it does not spread in the furnace and rather well holds a form.
4. The electric melting furnace is produced from available materials: tiled or cement tile, graphite and mica. The sizes of the furnace can be various and depend on the power of network and output voltage of the transformer. The this tension is higher, the it is more than a distance between electrodes. So, use of the welding transformer giving up to 60 V demands distance between electrodes about 200 mm. In this volume of the furnace it is possible to melt several dozen grams of gold or silver.
5. As electrodes brushes from a powerful electric motor will approach. At impossibility to use such brushes them it is possible to cut from a piece of graphite. Provide in an electrode sideways two openings with a diameter of 5 mm into which the multicore copper wire is inserted. On inside of electrodes a file make a notch for improvement of contact with graphite powder.
6. Mica serves as a futerovochny layer of walls of the furnace. It is a good heat insulator. Strengthen external walls a cement tile 10 mm thick. As a support for the furnace will serve the usual brick laid on the enameled metal pallet with boards.
7. Carbon and graphite powder can be received, having processed a file the cores which served the. In the course of melting, powder will gradually burn out and will demand replacement.
8. The assembled furnace is connected to the transformer by thick copper wires with external isolation in order to avoid short circuit. Warm up the ready furnace that further it worked without soot and ashes.
9. Melting happens so: in the beginning by means of a shovel in the middle of the furnace do a hole in powder, in it put the first portion of metal and dig in. If gold scrap of different size is used, then in the beginning place the largest piece, and in process of its fusion add small parts.
10. To make sure that metal melted slightly shake the furnace. The surface of powder will wave at the same time. After fusion, metal is overturned and again melt. So repeat until preparation does not take spherical shape (it demonstrates quality of fusion).
11. After melting metal preparations is subject to forging. The product should be tapped on an anvil a small hammer.