A homemade melting furnace can be made of graphite, cement, mica or tile. The dimensions of the furnace depend on the power supply and the voltage of the transformer at the output.
Tabletop melting table.
The home-made melting furnace heats up gradually, but reaches considerable heating. For this design, a voltage of 25 V should be installed on the electrodes. If an industrial transformer is used in the design, the distance between the electrodes should be 160-180 mm.
The process of making a homemade melting furnace
You can make a melting furnace with your own hands. Its dimensions will be 100x65x50 mm. In this design, you can melt 70-80 g of silver or other metal. Such opportunities for homemade melting device are very good.
Materials and tools:
- brushes from a high power electric motor;
- electrode rods used in arc melting furnaces;
- copper wire;
- cement tile;
- metal pan;
- carbon-graphite powder;
- thin conducting wire;
The scheme of the melting furnace of the transformer.
To make a melting furnace with your own hands, brushes from a high-power electric motor can be used for electrodes. They have an excellent lead wire.
If you can not buy these brushes, you can do them yourself from a piece of graphite. You can use a rod-electrode, which is used in arc melting furnaces.
On the sides of this rod, it is necessary to make 2 holes having a diameter of 5 mm, then, in order to give strength, carefully hammer a nail in there suitable for the size. To improve contact with the graphite powder using a file, you must perform a grid notch on the inner surface of these electrodes.
For the manufacture of the inner surface of the walls of the stove use mica. It has a layered structure and therefore can be used as a good insulating screen.
Outside the surface of the structure should be covered with cement or asbestos tiles, which has a thickness of 6-8 mm. After mounting the walls they should be tied with copper wire.
As an insulating support for the device you need to use a brick. Bottom set metal pallet. It should be enameled and have sides on the sides.
Then you need to make a carbon powder. It can be prepared from unnecessary rods. It is better to work with a file or hacksaw.
The scheme of the muffle furnace for melting.
When using a stove, graphite powder gradually burns out, so it is necessary to fill it up sometimes.
For operation of the device using a step-down transformer with a voltage of 25 V.
In this case, the network winding of the transformer should have 620 turns of copper wire, which has a diameter of 1 mm. In turn, the down-winding should have 70 turns of copper wire. This wire should have fiberglass insulation and a rectangular cross-section with dimensions of 4.2x2.8 mm.Back to table of contents
How to make a transformer?
If you can not buy a transformer with a sufficiently high power, it can be made from several transformers of the same type with lower power. They must be rated for the same voltage value in the network.
For this purpose, it is necessary to connect in parallel the output windings of these transformers.
You can make a transformer with your own hands. To do this, you need to prepare L-shaped metal plates having an internal cross section of 60x32 mm. The network winding of such a transformer is made of enameled wire with a cross section of 1 mm. It should have 620 turns. In this case, the down-winding is made of wire having a rectangular cross-section with dimensions of 4.2x2.8 mm. It should have 70 turns.
The scheme of the furnace for melting aluminum.
After installation of the furnace, it is connected to the transformer using copper wire having a thickness of 7-8 mm. The wire must have external insulation in order to prevent a short circuit during the operation of the furnace.
When the furnace is fully ready for operation, it must be well heated. At the same time must burn organic matter in the structure. During this procedure, the room should be well ventilated.
The device will work without soot. After this, the furnace is tested. If everything works fine, then you can start using the device.Back to table of contents
How to perform metal smelting in the furnace?
Melting of the metal is performed as follows. With the help of a small paddle (in the center of the stove) in a graphite powder it is necessary to make a small hole, put metal scrap there and drip it.
If the pieces of metal to be smelted have different sizes, then first of all a large piece is laid. After it is melted, put small pieces.
In order to check whether the metal has melted, you can shake the unit a little. If the powder is swaying, then the metal has melted.
After that, you need to wait for the billet to cool, then turn it over to the other side and melt again.
This procedure must be repeated several times, until the metal takes the form of a ball. In this case, it is believed that the melting of the metal is made with high quality.
The scheme of high-frequency installation for melting metals.
If it is necessary to melt sawdust or metal shavings of inexpensive metals, it is necessary to pour them into the hole of the powder and perform the usual smelting.
More expensive or precious metals should be put in a glass ampoule from under the drugs and melted with this ampoule. At the same time, a film of glass is formed on the surface of the molten metal, which can be easily removed by placing it in water.
Metals that melt easily need to be put in iron utensils. If you need to perform an alloy of various metals, then the metal is first put into the furnace, which melts worse. After it melts, add a low melting point. For example, to obtain an alloy of copper with tin, you must first put copper in powder, and then tin. To obtain an alloy of copper and aluminum, copper is melted first, and then aluminum.
In this device you can melt metals such as tin, iron, copper, aluminum, nickel, silver, gold. After the metal is smelted, it is forged. He is forged on the anvil with a hammer. In this case, it is often necessary to heat the workpiece on the fire red-hot, and then forge again with a hammer. After that, the metal is placed in cold water, and then again treated with a hammer, until the workpiece does not acquire the required size.
In no case should metals such as lead, magnesium, zinc, cadmium, and nickel melt be melted, because, burning out, they form a very toxic yellow smoke, which has a detrimental effect on human health. Silver contacts from relays and other devices cannot be melted, because they contain up to 50% cadmium.Back to table of contents
Compliance with safety regulations
When operating the device, it is necessary to observe safety measures:
- When operating an improvised melting device, it is necessary to handle the transformer very carefully.
- Do not allow short circuits in the electrodes of the device and in the wiring.
- The switch of the transformer must be at hand, so that at any time it can be immediately turned off.
- It is not allowed to leave the oven turned on unattended.
- When operating the device, a water tank should always be located close to which the metal will be cooled.
The self-made melting device made with observance of this technology will successfully work and carry out smelting of metals. In this case, it is necessary to comply with all safety measures.