Starting new 36" build

[deejayoh]

Re: Starting new 36" build

Chris -
I have the CF blanket - I am just waiting for the insulating rope and caulk that I want to use to seal my heat break. They were about the only place I found that had both, so I gave them my money and don't want the hassle of cancelling/reordering.

I could probably put on the blanket now and just peel it back to install the seal. There has to be a seam at the arch anyway.

[dvm]

Re: Starting new 36" build

deejayoh. I decided to put a "partial" heat break in my build. I will not interrupt the cooking surface to vent floor tiles, But I will isolate the oven arch from the chimney vent. I am planning to stuff a 1/4 inch gap with insulating braid. What type of caulk have you ordered?

dvm

[dvm]

Re: Starting new 36" build

While I'm at it - here's my first draft of an enclosure design.

I like the enclosure you have designed. - You have a knack with CAD! Are you planning to pour a concrete hearth? That is my plan - My step dad (a now retired contractor) recommended that I slope the poured concrete slab away from the oven - I would not of though of that on my own.
dvm

[deejayoh]

Re: Starting new 36" build

DVM -

Thanks. I am pouring a concrete landing. What I have read is 1% slope away from the oven is sufficient, so that's my plan. I am going to get the framing and siding in place and then pour that. I think. Not 100% sure about the order there. It might be better to build the front of the framing on top of the counter.

For the heat break - when it gets here, I am using Kaowool moldable. It's an insulating caulk - made up of the same stuff as the blanket and CF board that we have under our ovens

Kaowool Caulk Details

This weekend I cleaned up all the construction crap I had lying around the oven and took a load of brick chips to the dump. What a relief to have all that stuff out of the way! I am still going to make another mess putting the enclosure and cladding on the oven - but it's nice to have the brick dust out of there!

[texman]

Re: Starting new 36" build

DJ
Any thoughts on using the Kaowool or Inswool caulk in the crack that developed in your oven? They seem to be indicated for expansion joints. I don't know if the crack is a problem or just aggravation.
Tracy

[deejayoh]

Re: Starting new 36" build

Tracy -
Good thought. maybe I should use the Kaowool for sealing the crack. I was thinking about buying the black goop that others have used, but the caulk might be better, given it has some flex to it. Dome seems to want to shrink and grow with heat.

Dennis

[texman]

Re: Starting new 36" build

i was reading the description of the Inswool caulk and it indicated it is used for expansion joints and i remembered reading your thread and that you said it changes with heat. I don't think the crack is a problem that needs to be filled really. The insulation controls the heat and gases. The few embers that rise shouldn't be a problem either. I hope i am not dredging up the subject and you have moved on. The caulk might blend in with the oven after a few fires and not remind you it is there.

[deejayoh]

Re: Starting new 36" build

I have mostly moved on - but since I am still waiting for the caulk to arrive to seal up my heat break, I will probably also put some in the crack while I'm at it and call it good.

My biggest reminder of the crack is that two of the arch bricks are completely separated. I will definitely caulk that gap up so that I won't notice it. The crack isn't so bad that I get any smoke or sparks coming through the crack. It widens out to a couple millimeters, but you still can't actually *see* inside the oven.

Caulk is sposta arrive tomorrow, so I plan to goop that sucker up and get the insulation on this weekend.

In other news, I have tracked down a source for free cherry wood, and a guy with a truck/trailer rig who wants to split a load. No more burning concrete forms for me! Woohoo!

[dvm]

Re: Starting new 36" build

In other news, I have tracked down a source for free cherry wood, and a guy with a truck/trailer rig who wants to split a load. No more burning concrete forms for me! Woohoo!

Now that is a sweet turn of events! (some would say smokin)
dvm

[deejayoh]

Re: Starting new 36" build

Progress update: the caulk and ceramic fiber rope arrived as predicted on Thursday. I couldn't wait to get the heat break sealed!

I stuffed the 1/2 inch CF rope into the back of the gap - from the dome side. The gap wasn't entirely even. In some places the rope went in easily, in others it needed a bit of persuasion. Fortunately, I was able to get the rope in without cracking any bricks or groutlines. But the end result was a bit uneven, so I decided that I would put the caulk in from the oven side - where my gap was very consistent at 1/4 inch. I figured I could fill in the whole space between the arch and the dome - all the way back to the rope - with caulk.

The Kaowool caulk is white (I think at least one person had asked) and somewhat runnier than painter's caulk. I pumped it into the gap and smoothed it with a finger. In some places, it came out - I think because it didn't like to stick to the sooty bricks. But since there was an "L" bend in my air gap, I was able to get a good bond. Picture is below - after I lit a fire to cure it. Directions say to cure with heat.

Once the oven was hot, I waited for the crack to heat up and put some caulk in there as well. I could get so little caulk into it that it helped reassure met that it's a pretty small crack in the scheme of things.

Today, I got the CF Blanket on the oven and started putting down the steel stud track for the housing.

Tip for securing the blanket to your oven: I got a spool of rebar tie wire. It was $3.75 for 400 feet! It's just the right strength and malleability. I ended up cinching a loop around the bottom of the oven to pull in the blanket, and then ran wire back and forth through that loop and across the top to pull in the blanket. It was a cheap and effective approach.

Pics below...

[dvm]

Re: Starting new 36" build

deejayoh
Your build looks great and the pizza looks fantastic! Where is the small crack in your oven? Did you see any smoke escaping from the crack? If a small gap is present does is HAVE to be filled / covered with mortar or caulk? or would covering with ceramic insulation be sufficient? of course if you already have the caulk I understand using it - but is it necessary to fill every tiny (non-structural) crack?
dvm

[deejayoh]

Re: Starting new 36" build

DVM -
The crack ran down from the top of the dome through the left side of my opening arch. It was probably less than a millimeter across when open. It never leaked any smoke or anything, so the caulking was almost certainly superfluous. But I had the caulk gun out already to do the heat break, and also to use as a gasket for the chimney anchor plate - so I went ahead and used it up on the crack. But as I said, I could barely get any caulk into the crack, even on a hot oven.

Now that it's covered up with the blanket, I hope to never think about it again!

[dvm]

Re: Starting new 36" build

DVM -

Now that it's covered up with the blanket, I hope to never think about it again!

I vote focus on that great looking pizza and let the crack fade away.

dvm

[deejayoh]

Re: Starting new 36" build

I have had a busy couple of days working on the oven. I was on vacation from the 4th through Friday, and a buddy came over to help me on two of those days.

I got the lower box framed up on Wednesday all by myself. That was pretty easy. The only tricky part was that my chimney is right up at the front of the oven - so I had to cut into the steel tray to get around that. I did some bracing to stiffen the area up and it seems fine.

Worked on the roof on Thurs and Fri. First attempt at building trusses, I didn't like the design. Pretty much wasted a whole day on cutting and assembling those, only to decide that it wasn't going to work. Came back to the forum and looked at a couple other builds to figure out where I had gone wrong. I decided I liked the 2-piece approach that Dino and ggoose had taken. Friday, we cut and assembled the new trusses. Got most of the roof done. I will be finishing that up today and framing out the chimney.

Last night I had my first pizza party. Got the oven up to full temperature for the first time - cleared the dome completely. One new crack in the outer arch, but nothing inside the dome. Outside the dome, I can't see them anymore so I don't care

Cooked about 8 pies - if I get to count the one that I had to throw onto the fire . They came out great. I followed splatgirl's sourdough recipe for the crusts. I had a nice char on the pizzas and a good amount of spring in the crust. My biggest issue was getting them off of the peel in one piece. I was having some issues with them sticking - but all in all, it was a big success.

[Laurentius]

Re: Starting new 36" build

Deejayoh,

What sealing agent did you use on your oven stand to keep moisture from migrating from the soil, to the oven? I fear that you are going to have a major problem with so much of your oven embedded in the soil, hope I am wrong.