How big should the vent hearth be for a 36" Pompeii?

[wolvis]

Hi, I am just setting out my oven floor, and though I can see various versions on the forum, I am not clear about how large exactly the vent hearth should be and how it intersects with the ring of the bricks which create the dome. Has anyone seen any "typical" dimensions that I have missed, beyond the fact that it has to be at least 6"? Has anyone published more detailed drawings than the ones in the FB PDF?

[JRPizza]

I talk about this a little in my build thread which I linked below. I also have some cad files for a 36 oven I think I can pull up. I ended up going with a brick and a half vent area (13.5") - you can make them shorter or longer but lots of folks do the 1.5 brick.

https://community.fornobravo.com/for...319#post380319

[UtahBeehiver]

There are a lot of variables that impact the depth of the vent area, chimney type, ie SS double wall pipe, brick, clay tile liners etc. so there is no typical. If you use the double wall SS pipe, there is the anchor plate to consider, how much landing you want or have to work with. Most important is a smooth transition to the chimney vent is a good benchmark to work for. Look at JRs "S" shape brick vent work. Also make sure you vent area has at a min the same square inches of area as you chimney.

[wolvis]

I'm including a couple of pics to show what stage we are at, but it seems to be crunch time for which route to follow: whether or not to use a variant of the indispensable tool, or whether to go with some sort of form, either sand, styrofoam or plywood. I'm a complete newbie, so that will be a factor.

[wolvis]

[agrasyuk]

Guys above have good info linked to and there are other awesome builds on here that show this topic off with various depth of entry/chimney transition. "Brick and a half " sounds very good starting point.
do you have plans as far as chimney yet?

[wolvis]

Thanks! Not yet, a bit of wrangling going on between me and my wife about steel vs. terra cotta chimney.... I think the message is I need to get deeper into the detail of some of the builds here.

[JRPizza]

I think the majority of us were new to masonry when we built our first ovens, but it does not look like you are going to let that stop you! There are some old threads I read where some experienced brick layer's said the IT makes the build slower than just throwing bricks on a form, but an IT has it's advantages. You can see what the inside of the dome looks like as you progress, and I found once I got going that I could butter up a brick and use the IT to place it and "squish" it into place rather fast. I also am a mechanical type of person, so I not only enjoyed making the IT, but having a tool that would orientate that bricks in their proper place (distance and angle) gave me some confidence that I could actually complete a build.

[wolvis]

Thanks, I've been trawling through old threads on this and a Uk site, which feature some tight brick cutting, but a lot of them seem to have lost links to photos along the way. I confess to becoming mildly obsessed about how I provide the rebate for the door at the moment.