Having measured my kiln and the packing area I have to accommodate the new muffle (or saggar) I then made a plan on paper of the box like structure I was going to make to install in it.
Leaving 2″ clear space all round for the flame path was a suggestion that Joe Finch made, so that became my basic measurement.
Internal space minus 2″ all round.
When I had visited Joe to discuss the idea we had made a small model of how we thought it should work. Using this as my template I scaled up to measurements taking into account the shrinkage of the clay at about 10%.
I made a wooden frame which was the size of the largest piece of the saggar. Using sheets of canvas and working on large pieces of plywood I bashed and rolled the stiff clay into the frame. I scraped it down to avoid any air gaps.
To turn the slabs over I covered them in another piece of cloth, and another sheet of plywood. I then clamped the 2 sheets of wood together and flipped the slab over. This allowed me to work on the reverse side, smoothing out any air gaps and filling any weak areas.
I made 2 large pieces for the lid and the base. 2 square pieces for the back and the door, and 2 pieces with added sections for the side walls.
I added handles to the front door in order that it was easily removable.
Drying all of the pieces slowly proved a big challenge. I had to find space for each slab to have air circulating and at the same time drying slowly over a number of weeks in order that they neither cracked nor warped.
Finally after 6 weeks all of the pieces were bone dry, mostly not warped and ready for a trip in the car to a friend who has a very big kiln to fire them all in.
