40" corner build in central TX

[kbartman]

Re: 40" corner build in central TX

Thanks, KB. I'm hoping to get the outer arch done this weekend and re-set the center floor bricks, then next week tackle the chimney.

Speaking of chimney, has anyone done a squirrel-tail recently? I may need to be talked out of doing one

Not much eating on his tail.... I would cook the body instead

[ogorir]

Re: 40" corner build in central TX

alright, I fit the second plug in the top which I was able to get it out of the other half of the brick I used for the first plug. the mortar joint wound up a little big, between 1/4" and 3/8" but I wasn't going to re-do it over that.

It's a good thing I'm small and not claustrophobic, because I had to get inside the dome to finish grinding the arch tie-in. great time for the angle grinder to melt a winding and throw sparks around, right? After that excitement, I went over to HF and got a new grinder.

I decided to remove the bottom bricks I laid for the tapered arch because I had them cut and mortared solid to the dome arch and I wanted to taper them in and leave them un-mortared for a thermal break. I got 7 of 8 up before I ran out of mortar and called it a night.

I need to solicit some opinions for a hearth landing. I laid out my oven with the intent of having the dome arch tangent to the inner circle of the dome(like most people...) but it wound up tangent to the outer circle(derp) so I've lost 4.5" of landing in the front and I need to add more real estate.
The first option I'm looking at is cutting 2 notches into the 3rd course of brick above the storage arch, drilling in some rebar, and casting a monolithic butress/counter with concrete. I'd probably make the landing semi-circular to get more effective real estate with less weight.
My other thought is to do basically the same thing, but do it pre-cast so I can control the form better and cast it upside down on melamine. I think I could also make it a bit thinner this way and use the glass fiber reinforcement.

The real problem I'm not sure how to address is how to tie the counter into the existing structure, as there's only a scant 5" of surface outboard of the oven floor. The hearth slab is level with the top of the 2nd course of brick around the perimeter and it's poured up to the back of the face course above the storage arch, so I guess I can drill and anchor into that if I have to.

I really need to get this sorted out quick, I'm tired of messing up the floor in the archway because there's nothing hemming it in:/

[stonecutter]

Re: 40" corner build in central TX

Speaking of chimney, has anyone done a squirrel-tail recently? I may need to be talked out of doing one

Not recently, but I have done a few on historic beehive ovens. Why do you want to do one? It isn't going to benefit you, except if you want a center chimney, and that you can get by angling your flue.

Neapolitan vents have that style in front of the oven, unlike the ones I have done, which are rear vented. Neo oven builders claim a better draw from heat exchange from the uninsulated dome ( directly under the flue) into the flue chase. I have serious doubts about the practicality of that method, but that isn't the point.

It would be a conversation piece, and a lot of extra figuring if you haven't done it before. But who cares....it's your oven, do what you want.

I am designing another oven right now, which will have a traditional Neapolitan vent/chimney. But I am adding a layer of insulation over the dome before I build the flue over it. Consider doing the same if you go that route.

[ogorir]

Re: 40" corner build in central TX

The center chimney is what I'm after. How do you mean angling the flue? come up straight, then come back over the insulation and turn up again at the middle?

My non-aesthetic reason for contemplating center chimney is support. I have no idea if I'm going to get green tagged until I extend the chimney above the house roof, which I'm really not planning for, but I would have an easier time managing if the stack were centered on the dome. At least, I think I would. I didn't leave enough hearth stand on either side of the entryway to do any major buttressing.

I agree with you on the heat-transfer aspect of a true squirrel tail. the outside of the dome brick is going to take a proper long time to get anywhere near the temp of the inside, so while it may have an effect, it's probably not going to be relevant until your oven is heat-soaked. and by then, what's the point? as far as it goes, though, I think it'd be easier to run 3 courses of firebrick up the front of the dome than it would to angle that terracotta flue pipe.

It's mostly idle thought right now, I'm going to need to do the archway pretty much the same either way, so I'm going to get that done first. Then the landing overhang thing. At this point, I'm (predictably) regretting penny pinching on the base slab and block stand. I could've easily made it 8" larger both directions and been much more comfortable.

[UtahBeehiver]

Re: 40" corner build in central TX

nice brickwork on dome. congrats on the plug.

[ogorir]

Re: 40" corner build in central TX

Thanks Russell, I find it easy to pay attention to details when I'm having fun.

[stonecutter]

Re: 40" corner build in central TX

The center chimney is what I'm after. How do you mean angling the flue? come up straight, then come back over the insulation and turn up again at the middle?

Yup, but you wont be able to do it with clay flue unless you use strapping


My non-aesthetic reason for contemplating center chimney is support. I have no idea if I'm going to get green tagged until I extend the chimney above the house roof, which I'm really not planning for, but I would have an easier time managing if the stack were centered on the dome. At least, I think I would. I didn't leave enough hearth stand on either side of the entryway to do any major buttressing.

I don't know how high you need to go, but the last time I checked, IRC minimum clearance was 3' above the roof edge, 2' above the ridge on a gable end. That should be easy to check online.


I agree with you on the heat-transfer aspect of a true squirrel tail. the outside of the dome brick is going to take a proper long time to get anywhere near the temp of the inside, so while it may have an effect, it's probably not going to be relevant until your oven is heat-soaked. and by then, what's the point? as far as it goes, though, I think it'd be easier to run 3 courses of firebrick up the front of the dome than it would to angle that terracotta flue pipe.

I think you should do whatever you feel like, mainly because it doesn't matter how you run the flue as long as you get a good draw.


It's mostly idle thought right now, I'm going to need to do the archway pretty much the same either way, so I'm going to get that done first. Then the landing overhang thing. At this point, I'm (predictably) regretting penny pinching on the base slab and block stand. I could've easily made it 8" larger both directions and been much more comfortable.

Lessons learned if you build another one.

[ogorir]

Re: 40" corner build in central TX

"IBC section 2113.9 Termination. Chimneys shall extend at least 2 feet (610 mm) higher than any portion ofthe building within 10 feet (3048 mm), but shall not be less than 3 feet (914 mm) above the highest point where the chimney passes through the roof."

The oven is located 15 feet from both the garage and the house (local portable open flame ordinance) so I'm hoping that 3' is fine, as that's my plan

I'll probably just frame it up for a standard front chimney... I still have to tear out the old insulation in the attic, seal up, install radiant barrier, blow in new insulation... before the first.

[stonecutter]

Re: 40" corner build in central TX

Boy, my numbers were a bit dyslexic...but you got the point. The code I referred to was ICC...the IRC section R1003.9 Termination. Different acronym, same numbers.

[ogorir]

Re: 40" corner build in central TX

Oh, I looked up IBC 2009 because that's what the city has adopted. I should probably check NFC 2009 as well, which they also use.

[stonecutter]

Re: 40" corner build in central TX

You're good either way

[ogorir]

Re: 40" corner build in central TX

Well, T-day was a success. I didn't get the outside course of the arch done in time to cure, so it still looks funny, but it cooked the bird.

I cured the oven in a somewhat unorthodox way. I started a fire in the dome (no outer arch) on 11/18. I started with newspaper, then cardboard, then sticks, etc. for about an hour, which brought the dome to just under boiling inside. I let it rest for an hour while I was at yoga, then lit it up again when I got back, slowly building the temp from 6:30 til just after midnight. I don't remember the inside temps, but I almost got the dome boiled out, as the top reached 92C at it's peak and I had some steam from a few of the heat cracks. There were a few cracks that first fire, but not a whole lot. the only continuous crack ran concentrically between course 6 and 7.

over the next 2 days I built the chimney support and the outer arch. I actually laid the outer arch bricks once, but I knocked the chimney support brick loose cleaning up joints, then promptly managed to push the keystone out replacing it, so I pulled the whole outer course off.

I waited until this Wednesday to fire again to give the chimney support bricks time to cure. I set a section of chimney on top of the supports and fired from 5:30 to 1am, getting up to 300c or so under sustained flame. Thursday morning at 8am I was at 45c (it was cold for Texas at -1 overnight). I started a fire from the previous night's coals and fired from then to 2:30, stoking every 1/2hr or so. under a good fire I was seeing 400c, but most of the time it was between 250 and 300c. I did get the upper 2/3s of the dome above boiling on the outside at one point or another in the day.

I neglected to buy a decent uncoated roaster for the turkey, so I ended up using 3 disposable pans nested, which extended the cook time a bit. I always cut the turkey up first, so the backbone was removed and the breasts splayed and the legs were in a separate pan. the legs were done in 1:20 or so and the breast took just a hair over 2 hours to 160(barely. no one likes an overcooked turkey). I had them covered the first hour, but I'd probably only cover the first 30 minutes next time. The skin took way longer to brown than I was expecting.

So... Hopefully I can get the outer arch finished this week, maybe insulate too if I'm lucky. I'm thinking of using some kind of water barrier between the cal-sil blanket and the perlcrete, even if it's just building paper(that will likely combust, I know). Every time I've done perlcrete so far I wind up with a puddle under it where uncombined water has run out. I really don't want that in the cal-sil if I can avoid it.

also, what's the best stucco recipe for water-resistance? I know I'll need to treat the surface afterward, but there has to be some way to make the stucco more water-tight.

[Tscarborough]

Re: 40" corner build in central TX

Add marble dust, ie replace 2/3 of the sand with it.

[ogorir]

Re: 40" corner build in central TX

Sweet, I should be able to get some locally. Will granite work as well? there are a few granite countertop installers in town.

[Tscarborough]

Re: 40" corner build in central TX

No, granite will not, as far as I know. Check with pool supply places or drive to Austin.