Wednesday, April 7, 2010

Loading the Tamayaki

Last night we began to load the tamayaki, or wood fire kiln at Sara Yama Studio. The size, whether its glazed or not and the shape of the piece determines where it will be put in the kiln. The glazed pieces tend to go in the back, while the unglazed pieces go towards the front. The front is where the wood is fed into the kiln so it is lower temperature ideal for unglazed pieces, the back is the hottest part of the kiln, so glazed pieces do well there. The shape of the tamayaki is the key to firing the pieces correctly. The kiln is built on a slant, almost like a giant staircase. There are 4 steps, with a dome on each step and a small door on each dome (except the base dome where the fire is fed) Loading the tamayaki is not a one person job, it takes at least 4 people to put in pieces smoothly and efficiently. The pieces for the tamayaki are laid out in front of the kiln, and measured. The pieces with similar heights are put together, while odd sized and shaped pieces are put in last.

First stone slabs are prepared with sand spread thinly across the base. The pieces will be stacked on these slabs and the sand is to protect the kiln in case the glazes run or melt past the base of each piece. Since the tamayaki gets to 1200C the glazes tend to run more than if they were in an electric kiln. Where to draw the line of your glaze is usually trial and error, if you play it safe sometimes the result is a piece that isn't glazed to the base, if you take your chances the glaze could run over and then have to be chiseled off the stone slab, which could break your piece. Arai Sensei has a 3 finger rule. Leave 3 fingers of space from the base of your piece, 2 fingers for the electric kiln.

After the slabs are prepared they are then passed to Arai Sensei inside the kiln, where he carefully stacks them with pieces on top. Clay stackers, as I like to call them, make space between the stone slabs and allow the maximum amount of space to be used inside the kiln. It is very delicate and time consuming work, but once the pieces are stacked they are stable and won't fall down.

Inside the Tamayaki space is tight, so only one person can fit at a time. Arai Sensei is a small guy and even he can't stand up all the way. It is not for the claustrophobic hehe.

Each piece is passed inside one by one.

Look at the walls of the tamayaki, you can see its glossy. This is from the vapour of many firings before it. The bricks end up becoming glazed themselves!

We did not finish loading the kiln last night, but soon the stacks of pieces will fill this entire space, front to back, not a centimeter to spare. More pieces will be put in this Friday, then walls will be sealed and ready for the firing to start at 4am on Saturday morning. More to come soon!


  1. ah! loading/unloading kilns can be so nerve racking

  2. Yes! especially such a large one as this. But since theres so many volunteers the work gets done pretty fast