Starting Pizza Oven

[david s]

I email photos to myself which reduces their size, then you can post them.

[Michael Harrington]

Working on the oven again dome complete outer arch bricks cut what I need to figure out what size vent opening I need for a 6" pipe right now I have 4 3/4 width length in the works. Any help would be appreciated.

[UtahBeehiver]

calc the area if the ID of the chimney then the "minimum" rectangle opening need to be at "least" the same square inches.

[JRPizza]

Michael Harrington , I remember you saying something like math was not your strong suit. A 6" pipe has an cross sectional area of a little over 28 square inches (28.27433). You can get the minimum width of your vent by dividing that number by the depth you already have (4.75"). That operation will give you a width of 5.95", which I'd call 6 for simplicity. Six inches would be the minimum.

[JRPizza]

I forgot you were doing a serpentine arch. This is a good time to lay some bricks on their sides and see if you have enough room to transition to a minimum of 6" at the top. Remember you will end up with a rectangular opening (4.75 by 6+) and you will have to transition that to a square for your mounting plate. If you don't have a plate yet you need to stop and order one, and find out what the dimensions are.

[david s]

The combination of brick unit shape, gravity and thermal expansion/ contraction cycling introduces a very vulnerable weakness where the curve changes direction. Obviously not as pronounced as the drawing attached, but the same principle applies.

[Michael Harrington]

This morning I worked with the bricks and played with the bricks for the serpentine arch and I come up with four and three-quarter inches wide by seven and 3/4 the mounting plate I do not have yet but that is 9.8 inches if 4 3/4 wide isn’t enough. I can make it wider under the mounting plate by cutting off quarter inch or whatever I need to make wide enough under the plate. Do you think this will work? Thank you and I appreciate everybody’s help.

[JRPizza]

The 4.75 should be deep enough to feed your pipe with the 7.75 width. When the serpentine bricks are mortared in place it should look something like post #193 in my build thread. I added a side view below for clarity. The next step is to put a front and back on the bricks to frame in the opening, which I show in post #194, using 4 identical bricks that I cut a radius on so they would sit on the arch. After I mortared those in I added a few rows to get a good height and was able to install my adapter plate. I chose to do some through bolts but some have used masonry anchors or just a bunch of mortar. I thought I might get some side loads from my pipe being long and going through a roof so I went with the bolts.

[Michael Harrington]

I finished and insulated my oven. I want to seal the outside of the outer arch to making it easier to keep clean don’t know what kind of brick sealant to use just on the outer part of the arch