Kirk Mobert wrote:The mortar is clay/sand, again using locally sourced clay soil for the clay and locally sourced sand too. Cement based mixes can't handle the heat and should NEVER be used in stoves.
The plywood form is for making the arches. The bricks are laid over the form and then it's taken down and moved for the next row.
paul wheaton wrote:Old school bricks made from clay will do quite well.
Mjølner Rankenberg wrote:And what about the mortar?
I think that because my mix is really light (wood ash and all) it insulates well, which helps get the temps up. The other important detail is undersized bell leading to a hot chimney (not too hot, you'd have to work hard to get burned on it).
....The firebox mix is intended to be able to make anyplace in the world, by the poorest people.