Wood Fired Oven finished
http://www.flickr.com/photos/technopeasant [1]
Trying again ...
Let's see if the above works, first, before I continue ...
Finished my wood fired earth oven project. Took about two months and change, and I spent around $150 total. At the same time, I enclosed a side yard and made a private courtyard for entertaining and relaxing. Total cost of that was less than $300 because virtually all materials came from salvage and demolition sites. Good quality materials, at at that. Major costs were half dozen pressure treated posts and Quickcrete and various nails, screws, hardware.
Oven was built like this - foundation hole, sub-grade three feet to compensate for frost line. Built up a creek stone foundation to one and a half foot above grade, back filled with gravel. Top of this foundation wall leveled with mortar and salvaged brick to make a square and plumb foundation for the wood-form I used to pound out a rammed earth base for the oven.
Rammed earth base is 52" x 52" and I expect it to be a superb heat sink. Made of clay and clay silt soils from my property (this is desert SW, four corners area). Mixed with what our local supplier terms 'quarter minus fines' a grade of finely sifted gravel and clay. On top of the base went 4" of sand, then a layer of firebrick. Brick and Navaho sandstone for a lintel make up the door to the oven. Built up a wet sand mold of the oven void on top of the leveled firebrick, then molded a heavy clay/sand mix around the sand-form to shape what would become the interior void of the oven. Oven is 27" x 20"
Next, lots of cob. Cob are loaves of wet clay, sand, mud and chopped straw. Many many loaves to build up the mass of the surround to make up the mass of the oven itself. More mass, more heat retention. This thing probably weighs 2 tons, at least.
Removed the wet sand and revealed the oven void. Finished the outside with a sandy wet clay-slip. A coating of linseed oil just in case. And there you have it. Lots of physical labor and a fine oven that burns hot as that hot place in the afterlife.
Built a brick paver area around the oven for work space, all salvaged from a 1910 school being demolished. Roof panels and posts from a theater demolition and I have a dandy outdoor wood fired oven that works like a champ. I constructed two doors out of eight inch thick slabs of wood which I covered with sheet metal. One door for firing, which just fits inside the entrance, allowing smoke to exit the chimney, and a second door made the same way that's constructed to fit further in and occlude the chimney opening for 'soaking' the fired interior.
Pictures of bread and pizzas will follow. Hope you like it.