[EmcySquare] is delving into some hobby-blacksmithing by making his own knives. He needs a furnace to heat the metal, and after trying out a few different forge designs he decided to attempt an electric kiln build. The final project seen above is a box within a box. The outer shell is reclaimed using old computer cases and metal shelving brackets. Inside you’ll find a box made from fire brick, with stone-wool insulation to keep the heat where it’s supposed to be.
He cut the bricks to the right size to build the inner box, then added grooves on the inside edge witch will host the heat coils. This cutting was done with an angle grinder and [EmcySquare] notes that it kicks up an extraordinary amount of brick dust to make sure you’re wearing a respirator and goggles. Once the enclosure was ready he set out to fabricate the heat coils. Twelve meters of Kanthal A1 wire was used, shortened to a neat length by shaping coils around a 1 cm diameter wooden dowel. This prototype works but future improvements plan to add automatic temperature control through a thermocouple and a relay.