39" Oven in AZ

[Grtiz]

Hi I've been lurking on this forum for years and finally decided to speak up as I have moved forward with my build.

I'm not much on the math end of things as I seem to have gotten the short end of that stick of life but I'm great at building based off the back of a napkin and emulating others.

The build has started out emulating Deejayoh's oven with a dose of dtrbovich foundation.

[Grtiz]

Stand

We of course filled every other core and made some impromptu forms to handle the angles we cut in the stand. We ended up having to brace the altered cinder blocks on the front because we had a huge blowout when we filled the half open cores on the right.

[Grtiz]

hearth forms

I've been a huge fan of poured arch lintels and decided to take a stab at when we set up the hearth.

For the arch forms I ended up using 4 sheets of 2" foam covered in duct tape.

[Grtiz]

hearth forms removed

The hearth pour came out a little rough on top and I ended up filling in the bug holes on the sides of the pour with mortar.

[Grtiz]

Build Begins

I went to Marvel Masonry and picked up 200 bricks in the back of our minivan and I was very impressed that it could take the weight without bottoming out.

I also ordered the ceramic board and blanket from Mcgillis and it showed up the next day. Even with shipping it ended up being a few hundred less than sourcing it locally. So now I can start building.

[mrchipster]

Re: 39" Oven in AZ

Looks like you are well on your way to a great oven.

[Grtiz]

Re: 39" Oven in AZ

Had a chance to snap some photos of last weekends work. Covered the bricks with towels to let the mortar dry slowly and sadly I left the hose on top and it appears to have a slow leak from the nozzle. Ended up with soaked fiber board Need to let things dry out.

[Cyungle]

Re: 39" Oven in AZ

Great progress, Grtiz! At this point in your construction, would you have done anything differently?

I am also in Arizona and am just now building my hearth slab forms. It looks like our design and source of materials is very much the same, although I will probably have Marvel deliver the firebricks. I also had to put up a shade canopy - it is supposed to be 118F here this weekend!

My only unknown at this point in the construction is whether to build the insulation layer of the hearth slab over or underneath the reinforce concrete later. There seems to be a lot of debate about that issue.

// C

[stonecutter]

Re: 39" Oven in AZ

That's too bad. You should keep building though. The water in the board can work for you....cover your days work with plastic, and the evaporation of water form the board will create a nice humid environment for mortar cure( I'm assuming you are using fire mortar, not refractory). Keep the bottom of the plastic away from the dome base, because condensation will run down the plastic and you want it to drain off, and you don't want the water right back where it started.

[deejayoh]

Re: 39" Oven in AZ

Hey Patrick -

Looks good! I like the arch. To your PM question about the angle - yes, it is probably the height of your IT that is the difference. 12 degrees would be about a 3" difference between the height of your IT and the top of the vertical courses

Note that if you are using an IT with a higher pivot point you are going to get a taller dome. Check what the spreadsheet says for your measurements. I built mine flatter, which is why I used the plywood form. That had it's own challenges...

[deejayoh]

Re: 39" Oven in AZ

My only unknown at this point in the construction is whether to build the insulation layer of the hearth slab over or underneath the reinforce concrete later. There seems to be a lot of debate about that issue.

// C

I'm not sure I understand what you mean by reinforce concrete layer. Insulation should be between the brick floor and the hearth. I don't know that there is any debate about that. Some builders put a layer of vermicrete down, and then the board - but no one puts the insulation under the hearth.

[Grtiz]

Re: 39" Oven in AZ

Great progress, Grtiz! At this point in your construction, would you have done anything differently?

// C

Thank you. At this point I think the only thing I might have considered doing differently would be a larger stand.

I've been happy with Marvel though they did misquote by $.20 a brick. I debated doing the vermicrete layer but after mixing and pouring over 30 80lb bags of quikrete I think the fiber board is way to go. You would not believe how easy it is to work with.

[stonecutter]

Re: 39" Oven in AZ

My only unknown at this point in the construction is whether to build the insulation layer of the hearth slab over or underneath the reinforce concrete later. There seems to be a lot of debate about that issue.

// C

This has to be a misunderstanding...there is no debate about this. The insulation HAS to be under the floor brick, and not the structural slab.

[Grtiz]

Re: 39" Oven in AZ

Stonecutter,

Great call on covering it with plastic. I still have my sheeting that I used when I poured the slab and hearth so that should work a bit better than the towels I had anyway.

[Grtiz]

Re: 39" Oven in AZ

Dennis,

With that considered do you think the 7 degrees would work?

When you made the transition into your arch did you use a base template similar to the ones below it and just cut a 7 degree wedge off of it?