Monday, 30 December 2013

Building a wood fired bread and pizza oven - Casting the door lintel

Further progress has been made on my wood fired bread and pizza oven.  The supports have now been build that will hold the cast refractory door lintel.  They need to be left overnight to harden enough to position the lintel mold in place.  The shorter brickwork are the reducer arch supports.

Lintel and reducer arch supports

While the mortar in the lintel supports is going off, the mold has been made.  This has been knocked together out of some left over exterior ply.  the inside has been painted with vegetable oil, which will stop too much moisture from being absorbed, prematurely drying out the refractory and will make de-molding easier.

The mold is filled in thin layers, each layer compacted to remove voids.  The thin layers ensure that the matrix of stainless reinforcing fibers are aligned in the plane that will give the most strength benefit to the composite. This is the same technique used and described in more detail in my earlier post Casting the hearth slab.
Filling the mold with refractory
The will be kept like this until tomorrow night when i will de-mold.  I can fee the heat generated by the chemical reaction.
The filled mold hardening