Making of furnace for metal melt at home.

    The last stage is baking. Switch on the furnace through laboratory autotransformer, heating up gradually during 3-4 hours to 1100 degrees. Don’t try to accelerate this process; otherwise the water in the clay will boil in a moment and chamotte will swell.

    It’s better to use semistor power regulator instead of laboratory autotransformer. There are a lot of diagrams in Internet. It is cheaper, lighter in weight and more convenient in use. If you provide for such unit in advance it will make easier winding estimating.
   

   For example, I winded Fechral for 30 ohm, crucible was of 500 ml volume. Operating voltage for 1100 degrees is near 180 volt, so power is a little bit more than a kilowatt. Take into consideration the type of an extinguisher and crucible that I used… In a word, it’s almost impossible to estimate everything in advance. Control the process by monitoring devices.

   Attention!!! Water is highly conductive; the casing of the furnace must be securely grounded. Even if you have dried the furnace on a calorifer for a week, don’t doubt that there is a lot of water left! You’ll distinctly observe steam and hear hissing. Chamotte itself contains a number of conductive oxides. So there must be the grounding.

   It’s natural that before starting the modding you should realize that this work is for persons skilled in technique only. Crucible with molten copper is a dangerous thing in tremulous hands!!! Be very careful, molten copper is heavier than it seems . Think over a clutch for carrying it, because the crucible edge can be easily broken off by combination pliers and you may spill the precious contents on yourself or on your dearest mother-in-law. All operations must be carried out on an incombustible surface in a well ventilated room. Concrete floor of a balcony is ideal place. It’s better to melt aluminium in an iron cup; copper wire should be pressed with a hammer, otherwise it will be cindered.

If somebody decides to do such modding, place your photos of the modded device here