In order to make dishes from clay a little to mold it, you also need to burn it properly. The firing temperature of clay products is 1000 ° C. Therefore, only a special furnace can cope with this task.
There are two types of muffle electric kiln, when the heating element is located around the container of refractory (muffle), and chamber. In the chamber furnace, the heating element is inside the tank. It was the chamber oven from the old washing machine that the author decided to make.
Tools and materials.
Washing machine body;
Welding machine;
Refractory brick;
Heating element (spiral);
Basalt cotton wool;
Refractory masonry mixture;
Wiring materials;
Metal sheet;
Trumpet.
Having disassembled a washing machine, the author leaves only the casing from it.
Since the load on the furnace body will be large, it strengthens the lower part by welding across the 15mm pipe. It also strengthens the upper side and rear walls. At the corners of the lower part, legs are welded from pieces of pipe of a larger diameter.
From the inside, a square pipe is welded to the bottom of the furnace, as if dividing it into sections.
Lays basalt cotton wool on the bottom.
Cutting to size, covers the bottom with a sheet of iron. A brick begins to lay on iron.
For laying brick on an iron sheet, cement is added to the refractory masonry mixture in a proportion of up to 30%. If the brick is laid on brick, cement does not need to be added.
Having soaked a brick as densely as possible puts it on the prepared solution.
He spreads the walls so that they taper upward, forming a trapezoid. Between the brick and the body he puts basalt cotton wool and covers it with a sheet of iron.
The door is also laid out with bricks from the inside, reinforced along the perimeter with a corner. Hinges are welded to the door.
Further, in the brick, it hollows out a groove for the heating element. The furnace will have two independent circuits.
The heating element is a spiral of nichrome wire with a diameter of 1.5 mm. The coil of a spiral is about 12 mm. Having laid a spiral in the groove, so that it would not touch each other, fixes it. The ends leads to the top.
Fastens the ends of the spiral on the distribution rail.
Next sets the switch. For the furnace, the author installed a switch, when turned on, one circuit or two works in series or in parallel.
Now, when two circuits are connected in series, the furnace begins to warm up with an average temperature.
Having switched the switch, one lower circuit starts to bask at full power. Once again turning the handle of the switch, two circuits are connected in parallel and the furnace warms up to the highest temperature.
