Techno Tips - The Kiln Goes Up & On | Lids and Bases A double brick base was built for additional insulation. The bricks | were stacked on top of each other, off setting the cracks to minimize heat escape. A stainless steel band bound the two layers together, separating the base from the kiln's main body for ease of dismantling. Two types of insulating brick, K-23 and K-26 were used. The K-26 brick is the top layer of the base, it is heavier but offers a more sturdy kiln floor. The K-23s were used on the bottom layer of the kiln base and the lid. Lighter in weight, the K-23 lid is easier to lift and is also a better insulator. On the large kiln, the lid bricks were mortared together to add strength and conserve heat. On the smaller kiln, one layer of K-23s was topped with Kaowool to increase insulation. A wider lid stainless steel band was made to accommodate the extra thickness and a circular aluminum top was cut to cover the Kaowool. Small aluminum brackets were made and attached to the lid band with small, metal! screws. The first step in building the lids and bases was to make a hardboard template matching the circumference of the kiln with a hole drilled in the centre so that it could be bolted to the grinding table. The circle’s centre is lined up with the centre of the downward-rotating side of the cup head and is exactly the distance of the radius of the circle away from the grinding wheel. The bricks were laid out on the board, using scraps where possible. Salvaged and partial bricks were used for the corners and ends. One advantage to using soft insulating brick is that a rough cut can be made with a wood saw first, minimizing the amount of material needed to be ground off. 2. BRICKS ARE THEN ASSEMBLED ON A WOOD TEMPLATE THAT Aiter the bricks were all assembled and laid out on the board, a pipe-clamp was used to applied pressure to the majority of the bricks while being rotated clockwise on the grinding wheel (see apparatus for rounding bricks Diagram). Additional hand support was necessary when passing the outer bricks into the wheel. The pipe-clam had to be continuously repositioned when it approached the wheel. It was discovered that was much easier to grind the circle of bricks if are mortared together first. The clamps are cumbersome to use and the bricks always shift a little. After the bricks have been ground, bind them together with a stainless steel band measuring 2” wide for the lid and 4 1/2” wide for the double layer base. Each band has two hose-clamps riveted to it, so it can be tightened around the bricks. Two handles were also riveted to the lid-band. Finally, the edges of the lid were rounded with a scrap piece of brick to prevent chipping. Rounding the WallBricks For rounding the wall bricks to match kiln's circumference, use the same grinding set-up that was used for the lids and bases. However, a smaller pie-shaped arm was constructed to rotate the bricks into the grinding wheel with wood supports to hold the brick in place (see Apparatus for Rounding Bricks diagram). The arm pivots on a 3/8" bolt that is securely bolted, but still allows the arm to swivel. The large kiln requires 11 rows of 10 bricks each, plus one more row for the extension ring, totalling 120 bricks. The small kiln used 7 rows of 8 bricks each for the walls, plus one extra set was prepared for the extension ring, totalling 64 bricks. To be Continued... Report prepared by Julia Maika and Matthew Church. APPARATUS FOR ROUNDING BRICKS 14 SILICON CARBIDE WHEEL 6"“cuphead 1.ROUGH CUTS MADE FROM SALVAGED ANDY NEW BRICK WITH = WOOD SAW MATCHES THE CIRCUM— FERENCE OF THE KILN BOLTED TO TABLE, “