The building of the outer wall went smoothly and quickly, incorporating the ceramic fibre blanket insulaton as it was built. We kept to a thickness of 2", but widened the wall at the top to create a shelf. (In the event, this could have been either about 1" wider or not created at all, except for under the mullite slabs we used as gathering hole floors.)

The problems appeared as it dried! We had not allowed nearly enough shrinkage space, naïvely thinking that compressing the ceramic fibre blanket would fully compensate. It turned out that we should have allowed about another inch or inch and one-half of space around the wall - both for shrinkage on drying and on firing (even though the outer wall did not fire to a high temperature in subsequent firings).

Nevertheless, we were able to fill the cracks that appeared as the wall dried, although we had to do this several times).

We also had to work on the top of the wall, filling in several dips and generally keeping it horizontal and at the same height as the inner wall (even though we had built the outer wall higher than the inner wall). We also needed to adjust the slots for the floors of the gathering holes that we had cut into the outer wall. Clearly, adjustments when building an outer wall around a fired inner wall need to be carefully thought through.

At this time, we also made two slots under the front of the gathering hole tunnel. These were to allow for the insertion of a steel bar which functioned as a support for the wood during firing, allowing air to reach the underside of the wood.