How to build chimney and outer arch

[stonecutter]

Re: How to build chimney and outer arch

I?m thinking the semi circular arch should not require any buttressing. Any thoughts appreciated.

Correct, no buttress required.

[kbartman]

Re: How to build chimney and outer arch

I?m considering uses insulated fire brick placed directly on the hearth below heat break arch and outer arch. I didn?t like the idea of setting these on floor insulation. My plans are still try to using the two 9x18x24 clay flues on top each other. I?m thinking the semi circular arch should not require any buttressing. Any thoughts appreciated.

[Gulf]

Re: How to build chimney and outer arch

Gulf,
Sorry I haven?t responded earlier, been quite busy lately. My original plans were to build a full size chimney. Then I got scared about the weight and the overall height. I need to grow so gahones to tackle that.

Meanwhile I do have a few questions and need clarification on how to begin the outer arches / heat break. I like how you cut the notch in your brick to accommodate the heat break. The ? inch ceramic rope, how did it work and are you happy with it? Would you have done it differently? I?m considering the same size rope or double or tripling the ceramic band I used around the floor, and wondering what size gap you would leave? Would you recommend me setting the outer arches on insulation concrete or just the concrete hearth? I considered setting these on the floor insulation.

The plan at this point is to use the rebar sticking out of the hearth to help support about 8? poured counter top extension from hearth stand face and the additional height to meet oven floor. What your thoughts?

Edit: give me

Pics attached:

I don't think that I would do too much differently (that is, in my case as I was wanting to build a multiple use oven, case not proven as of yet) I used 1/2" and 3/4" rope for the notched heat break. I think that the same effect could have been accomplished by just setting the outer arch overlapping the inner arch without notching. (a full width brick reveal). The outer arch/entry could be then built (like most entries) without a flare,but with the same clearance as one for working the oven.
That would decrease weight for those wanting to set ss flues ', but would require some additional buttressing if they wanted to include a toned down version of my chimney style.

Edit:

Would you recommend me setting the outer arches on insulation concrete or just the concrete hearth? I considered setting these on the floor insulation.

I wouldn't set anything on the concrete hearth but face brick. That is, only if they were separated from the outer arch by a heat break.

Please.give me one more day to reread your entire post. I have to get up for work at 3AM

[kbartman]

Re: How to build chimney and outer arch

Gulf,
Sorry I haven?t responded earlier, been quite busy lately. My original plans were to build a full size chimney. Then I got scared about the weight and the overall height. I need to grow so gahones to tackle that.

Meanwhile I do have a few questions and need clarification on how to begin the outer arches / heat break. I like how you cut the notch in your brick to accommodate the heat break. The ? inch ceramic rope, how did it work and are you happy with it? Would you have done it differently? I?m considering the same size rope or double or tripling the ceramic band I used around the floor, and wondering what size gap you would leave? Would you recommend me setting the outer arches on insulation concrete or just the concrete hearth? I considered setting these on the floor insulation.

The plan at this point is to use the rebar sticking out of the hearth to help support about 8? poured counter top extension from hearth stand face and the additional height to meet oven floor. What your thoughts?

Pics attached:

[Gulf]

Re: How to build chimney and outer arch

My dome is almost complete.........pondering the chimney and vent....(??).....will have a thermal break and chimney modeled after the Mississippi Queen?.. Need all the help I can get???..

That is very flattering KB,
I hope that you have looked at other builds very closely. The MQ has been a fun ride , and a lot of work! But, then I again I will paraphrase a sayin' from my other interest. "It's all about the build"

[kbartman]

Re: How to build chimney and outer arch

My dome is almost complete.........pondering the chimney and vent.........will have a thermal break and chimney modeled after the Mississippi Queen?.. Need all the help I can get???..

[david s]

Re: How to build chimney and outer arch

With that kit you would be better off placing the thermal break between the entry sections and the outer decorative arch (assuming you are building one)
Separating the outer shell and arch so the inner oven parts are free to expand and contract is a good way to prevent cracking in the outer parts.

[RichC]

Re: How to build chimney and outer arch

I hadnt considered it Gianni! Is it worth considering?
See attached image of the kit that I'm using. I'm thinking of using the chimney structure they provide which is 3 section thing with a cutout for the flue in the top section. How would you go about building a thermal break into that?
I've been consdiering building a brick chimney but I might just go ahead with the parts in the image. The sections in the image bond to the dome with refractory mortar? What do you think?

Thanks

Richard

[GianniFocaccia]

Re: How to build chimney and outer arch

A thermal break is an engineered gap between the adjoining oven arch and the entryway arch. The purpose of this break is to minimize the contact area between the two structures in order to limit the amount of residual oven heat loss through the entryway once pizza oven temps have concluded.

[RichC]

Re: How to build chimney and outer arch

By thermal break do you mean insulating layer? Hadn't thought about it. What's the pros and cons?

[kbartman]

Re: How to build chimney and outer arch

Are you going to incorparate a thermal break between the chimney and oven?

[RichC]

Re: How to build chimney and outer arch

Still working on deck so chimney is in planning phase

[kbartman]

Re: How to build chimney and outer arch

Looks excellent kb, perfect form work.

Btw, I think I did actually hear about that guy that went down the sinkhole, it was quite a while ago wasn't it?

Yes that was quite a while ago. Tragic

Hows the chimney build coming?

[RichC]

Re: How to build chimney and outer arch

Looks excellent kb, perfect form work. My own arch bellied slightly in the front doorway so ill probably have to reshape part if it with a consaw. I assume its ok to pour the 3.5" slab with no airgap as it'll be we'll insulated from the actual hearth? My original build was from 'The Breadbuilders' book and the slab was part of the hearth so required an airgap. Now that I'm sitting a prebuilt dome and hearth on 4.5" vermicrete above the slab I suppose I don't need an airgap? Any thoughts in that?
Also, can I put fibre blanket down and pour the vermicrete onto it or would that make any sense?

Btw, I think I did actually hear about that guy that went down the sinkhole, it was quite a while ago wasn't it?

[cobblerdave]

Re: How to build chimney and outer arch

Gudday KB
Forno oven stand is grossly over built to start with and yours in the true tradition is also! My own stand carries 170 odd firebricks and 200 odd house bricks in the dome and chimney.no worries.
Regards dave