Brick o' knowledge
Feb. 23rd, 2015 07:31 pm![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png){kind=small}
offcntrTime for some definitions again?
Hot face. The inside surface of the kiln wall or door. (Cold face is obviously the outside.) Because brick expands and contracts with heating and cooling, these will tend move away from each other unless tied together by brick set to connect the two.
Kiln brick comes in several varieties, also shapes. For this job, we only used standard straight brick, 4.5 x 9 x 2.5".
Hard brick. A dense, high alumina heat-resistant brick. Very good in high-stress environments, like the flame channel (in front of the burners), bag wall or chimney flue. Not generally used for an entire kiln, because it absorbs too much heat, so uses more fuel to fire. Exceptions are wood or salt kilns, wh6ere the kiln atmosphere is corrosive to soft brick.
Soft brick. Also known as insulating firebrick. Heat resistant brick that's been formulated to be porous by mixing in sawdust or diatomaceous earth. Because it's riddled with air pockets, it absorbs less heat, so a soft brick kiln is more fuel efficient. Soft brick is rated by temperature: K23 is recommended to fire to 2300° F., K26… you get the idea. Technically, cone 10 is a little over K23, but not by much, so we still use them in stoneware kilns.
Kaowool. Ceramic fiber insulation, an offshoot of the space program. It's what's underneath the tiles on the space shuttle, a thick, white layer like slightly crunchy cotton. Incredibly fuel efficient, but nasty to work with, as the fibers become fragile with too much heat, get airborne, and are very bad to breathe. There are ways to make a kiln of this stuff, but at Club Mud, we reserve it for extra insulation on the cold face, over the arch, for example, or to pack into gaps.
Sairset. A brand of high-temperature kiln cement. We've used it to repair broken bricks in the electric kilns, and to attach brick to the steel top lintel of the stoneware kiln door.
Bag wall. A structure to redirect flame. Ours deflects flame from the burners upward to curve under the arch, through the pots and out through a channel in the floor of the kiln. Without a bag wall, the flame would hit directly only on the bottom pots, and the top of the kiln would be consistently cold.
Hot face. The inside surface of the kiln wall or door. (Cold face is obviously the outside.) Because brick expands and contracts with heating and cooling, these will tend move away from each other unless tied together by brick set to connect the two.
Kiln brick comes in several varieties, also shapes. For this job, we only used standard straight brick, 4.5 x 9 x 2.5".
Hard brick. A dense, high alumina heat-resistant brick. Very good in high-stress environments, like the flame channel (in front of the burners), bag wall or chimney flue. Not generally used for an entire kiln, because it absorbs too much heat, so uses more fuel to fire. Exceptions are wood or salt kilns, wh6ere the kiln atmosphere is corrosive to soft brick.
Soft brick. Also known as insulating firebrick. Heat resistant brick that's been formulated to be porous by mixing in sawdust or diatomaceous earth. Because it's riddled with air pockets, it absorbs less heat, so a soft brick kiln is more fuel efficient. Soft brick is rated by temperature: K23 is recommended to fire to 2300° F., K26… you get the idea. Technically, cone 10 is a little over K23, but not by much, so we still use them in stoneware kilns.
Kaowool. Ceramic fiber insulation, an offshoot of the space program. It's what's underneath the tiles on the space shuttle, a thick, white layer like slightly crunchy cotton. Incredibly fuel efficient, but nasty to work with, as the fibers become fragile with too much heat, get airborne, and are very bad to breathe. There are ways to make a kiln of this stuff, but at Club Mud, we reserve it for extra insulation on the cold face, over the arch, for example, or to pack into gaps.
Sairset. A brand of high-temperature kiln cement. We've used it to repair broken bricks in the electric kilns, and to attach brick to the steel top lintel of the stoneware kiln door.
Bag wall. A structure to redirect flame. Ours deflects flame from the burners upward to curve under the arch, through the pots and out through a channel in the floor of the kiln. Without a bag wall, the flame would hit directly only on the bottom pots, and the top of the kiln would be consistently cold.