The kit is designed for melting and casting metal and alloys in small volumes using a microwave oven with a capacity of at least 700 watts. The furnace does not require any alterations. Recommended installation power for operation is 600 watts. This is approximately 1-2 divisions less than the maximum power on the rotary kiln controller.
Using the kit, you can melt aluminum, bronze, copper, silver, gold, cupronickel, nickel silver - i.e. metals and alloys, the melting point of which does not exceed 1200 degrees. It is impossible to melt steel, cast iron, titanium, platinum - since the melting temperature of these metals is much higher than 1200 degrees.
Warming up to a temperature of about 1200 degrees is due to the special material of the crucible that converts microwaves into heat.
A special heat-proof box keeps the temperature and prevents the microwave oven chamber from overheating.
The volume of the crucible is 20 ml, which allows melting up to 300 grams in gold or 150 grams in bronze. Melting time is 6 - 8 minutes with an installed power of 600 watts. Aluminum melts faster. The exact melting mode is selected experimentally.
Resource crucible with careful handling is at least 50 heats.
The material of the crucible does not require additional treatment with boric acid.
Melting metal in a kitchen oven where food is heated is not recommended. It is better to use a separate microwave. Moreover, the simpler - the more convenient, since in complex button models, auto-regulation is used, which is difficult to work with.
The main thing is that there should be a timer and a power of at least 700 watts. The rotation of the disk inside the furnace is not essential.
Crucible - 1 pc.
A heat-proof box consisting of a solid base plate, a lower fiber insert without a hole, three fiber inserts with a hole for a crucible and an upper fiber insert-cover without a hole. .
Crucible tongs - 1 pc.
HB gloves - 1 pair
Fiber plate for the extracted box - 1 pc.
Put a layer of fiber without a hole on the solid heat-protective tile of the box. Next 3 layers of fiber with holes. Put the prepared metal in a crucible. The metal must be free of contamination and in no case wet. Avoid pressing while laying.
Do not melt parts of mechanisms inside which there may be air or plastic - this can lead to an explosion. Make sure there are no steel parts - they can wedge the crucible and ruin it.
After installing the crucible with metal inside the box, cover it with a layer of fiber without a hole.
Transfer the crucible box thus assembled into the microwave on a rotating stand. Set the timer for 7 minutes (for 60 g of copper, bronze, precious metals) and, having closed the door, start heating.
After about 6 minutes, the glow of boxing will begin. Wait another minute, put on gloves and open the oven door. Carefully, with both hands, grasping the bottom hard heat-shielding tile, take out the box and transfer it to the fiber plate. Do not hurry. Open the top fiber insert. If the metal has not melted to the end, close the box and heat it up for another 1-2 minutes. It is possible outside the oven.
After making sure that the metal has melted, if necessary, treat it with flux and remove the slag.
The thermal inertia of the crucible in the box is enough to carry out these operations without haste.
Next, remove another layer of fiber. Take the tongs and grip the crucible. If the fiber sticks, slightly stir the crucible. Transfer the crucible to the prepared dried form and cast.
The next heat is preferably carried out after 10-15 minutes to allow the microwave to cool.
In general, the casting process and working with high temperatures require great accuracy and concentration. Serious injuries can result from an irresponsible approach.
Please read the following safety precautions carefully.
If you have never been involved in metal casting, familiarize yourself with this process first. For example, on the subject of "jewelry casting."
1. On a surface of a table where molding will be carried out, lay a sheet of metal. It is convenient to use a metal pan or baking sheet.
2. The work area should be well ventilated during operation and be safe in fire.
3. Before starting work, prepare all the necessary tools and draw up a sequence of operations.
4. Be sure to use gloves and long-sleeved clothing.
5. Do not keep flammable materials near the workplace.
6. Do not store anything on top of the microwave.
7. Keep children and animals away from the work area.
8. Never put materials into the crucible if you do not know their properties. Tempered glass can explode, for example. Combustible inclusions can cause ignition of the furnace and fire. Metal and organic salts can lead to the formation of acids and toxic gases.
9. Do not melt tin, lead and zinc. They have a low melting point and the metal can boil and splash out. In addition, the evaporation of these metals is extremely dangerous to health.
When melting aluminum, sometimes it is necessary to help drain with a steel spoke, since with a low specific gravity and strong surface tension, aluminum is poorly poured out of the crucible.
10. Do not leave a working microwave unattended. When finished, make sure that the heated crucible and box do not ignite any objects and are safe for others.
11. Handle ceramic fiber inserts carefully. By themselves, they practically do not collapse and with normal use will last a long time.
12. The crucible can withstand guaranteed 50 heats, after which it should be carefully inspected for cracks and chips, without waiting for complete destruction. Before melting, carefully inspect the crucible every time.
For each metal, it makes sense to use a separate crucible.
13. Do not melt metal without a heat shield; this will cause the microwave oven to overheat and break.