Brick Oven Mouth Construction

How appropriate for an object that makes food to have a mouth. One oven I repaired was fashioned in the shape of a turtle and the mouth was the mouth.  But seriously, very seriously, the mouth and throat of a brick oven presents the most challenging masonry techniques.

The requirements of the mouth and throat (the area just above the mouth in this case) include:
1. The easy and safe introduction of fire to the oven interior.
2. The smooth passage of smoke from the burning fuel out the chimney.
3. A shape that allows handling whatever is cooked in the oven with ergonomic logic.

The construction of a mouth that meets the above requirements varies. Many of my portable ovens have angle-iron lintels that carry the load and shock of a masonry unit in motion on the road.
The most appealing mouths have brick arches, usually with a slot above that is the throat. In both cases this throat area is larger than the chimney and channels flue gases up and out rather than having them spill in front of the face (the outer front) of the oven.

My original portable oven, although white stucco on the face, is still white after four years of frequent firings.

Angle-iron lintels are easy. The three heavy angle-irons lay level on top of the side bricks of the mouth.
Arched mouths must be built with an arch form and need sufficient side support to contain the outward force of the curved arch bricks.

Some ovens have deep mouths that prevent easy access to all areas of the cooking space within the dome. After observing ovens in Italy and France as well as baking in my own oven, I began building oven mouths that angle considerably from back to front. This allows the baker to access all edges of the interior of the oven without expanding the actual oven opening beyond the recommended proportions for efficient firing and heat retention.