Things seem to be running from bottom to top - not sure what to do about this so you,ll have to bear with me. I'll get onto the dome now - need lots of sand to create it! I put some bags of gravel at the bottom of the dome to help give it a higher base to build on. Then it was a matter of forming a dome and trying to maintain the shape. I mixed quite alot of water with the sand and beat with a piece of wood to try and compact it other wise at a certain height it just starts to fall off and you don't seem to be getting anywhwere. Damp newspaper was laid on the sand dome to prevent the clay sticking to the sand and making it easier to get the sand out once the clay dome has been formed.
The clay mix was 25% clay and 75% sand mixed to a smooth consistency.
Once the first layer of clay has been put on, I left it for about 24hrs before cutting out the door and removing the sand. Then had to cut a little more out for the chimney, constructed from industrial sized tins of tomatoes with the bottoms cut out. This gave achimney of about 6ins diameter which works really well and gives a good draw for the fire. Having done this I felt I had to try it out and lit the first fire to help dry the clay!
Now it was just a matter of adding more clay to the dome for insulation. I mixed clay, sand and horseshit to get a really smooth consistency and then just kept lathering it on - can't remember how many layers I eventually did but I guess the oven is about 6-7ins thick.