Flue Gallery Buttressing

[TARibs]

Every time I think I have things figured out I find something else to worry about. Cast dome is built and I'm pretty happy with that result, working on Flue Gallery, Plan was to use some old regular fire brick for Side walls make a decorative arch front and back, Land a cast Flue on top of the side walls and stick a stainless pipe on top of the flue. So I get to thinking how much outward pressure will I be exerting on the side walls? The arch bricks are likely going to be thin due to space constraints. Real pressure should be downward from the Flue and Stainless pipe. Do I need to buttress those side walls or create some type of wing wall for stability? I won't be leaving gaps in the bricks like the picture if I do put in a wing wall that was just for modeling the wing wall. Going to attach some pics to give everyone a better idea of what I mean. Would love to hear others thoughts on the matter?

The rest of the build pics and questions can be found here https://community.fornobravo.com/for...products-vt600

Thanks
Tom

[david s]

I don’t quite understand why you need to build a brick arch, unless the height of your oven mouth is wildly too high in relation to the internal dome height. If that is the case you could consider casting a thin(say 2”) section both sides and arch in front of the oven mouth, then the flue gallery in front of that, thereby eliminating an arch in brick. The flue gallery casting can be made way thinner and therefore way lighter than a brick one, hence no need for buttressing. Make sure the flue gallery is larger than the oven mouth so it provides a rebate for a door to sit against which will isolate the oven from the flue gallery.

[TARibs]

The flue Gallery was poured last night into the mold, It's only about 1-1.5 inches thick probably thicker at corners. It is heavier than I thought it would be but maybe that's partially the mold and the fact a lot of the water hasn't worked its way out yet, No issue with the present opening size. I just like the look of the brick arch in the front. I guess if I land it correctly on the side walls there won't really be lateral pressure from the top of the flue and the arch is going to be very small and shouldn't exert much pressure its really more decorative. I just but wanted to see what others thought.

[Chach]

i did a cast arch with a flue on brick side walls. I am enclosing mine so I won't see tje cast unless i stick my head in....you can always cast it and if your not enclosing it you can insulate render and veneer an arch and you probably wont know the difference I also made it taller than needed but now i dont need as much flue pipe on it only a 3' piece for me. Here it is in the picture.

[TARibs]

Yes Chach that is pretty much exactly what I was thinking. Only difference would be I would come out maybe another third of a brick and put in a brick arch more as a decoration for the entrance to the flue gallery. I'm guessing all the pressure is down on the bricks from the cast piece rather than pushing out, it will only be that small arch of bricks (for that matter I could make them almost a veneer in keep them and inch thick. Thanks I fell better about things now. Love the build by the way, its very similar to my plan with the granite tops, (I probably won't have the frig and grill however just a prep table (although it does give me ideas). Friend was getting rid of their old granite when they redid their kitchen and told me I could have it (score!)

Curious Chach do you have a completed picture of your oven (and the whole patio area), didn't see one in the link

Tom

[Chach]

Thanks! I'm still working on the enclosure i just started up again thst is the latest picture..once i get the flue in ill close the front and be ready to stone.

[TARibs]

So I took the casting out of the mold today and looks to have worked very well. Set it up on the bricks and even attached the chimney and cap to have a look at what I should end up with. And I liked it :-) now I need to get those bricks mortared in place. Still planning a brick decorative arch in front when its set up, but it won't be very thick so not concerned.

[david s]

Tom, I think I may have misinterpreted the pics on your post#1. I thought you were planning a brick arch between the flue gallery and the oven, but it seems you haven't. Apologies for the confusion. Your build looks great and I'm sure your flue gallery will perform exceptionally well.

[TARibs]

So it took a while but flue gallery is done, the mounting bracket for the Vent pipe was fixed in place with a combination of high temp adhesive and Vermicrete, then I place the precast gallery on the brick sides I'd built. then used vermicrete in the small space acting as an expansion joint between the oven and flue gallery, finished it off with a brick arch over the entryway. So fingers crossed nothing moves too much to cause cracks. Next step is going to be 3 inches of blanket followed by a stucco layer, (don't think I have the space for another vermicrete layer) and watching the Forno Bravo videos that is how they seem to do their ovens. I'm only planning a single inch of blanket over the flue gallery piece. Hoping to get most of that done this weekend. I'm wondering what thoughts are with regard to 1st curing fires? Should I build the fires before or after placing the stucco? I've seen some discussion here about moisture escaping and don't want it trapped by the stucco layer? Can't wait to start a fire in this thing, getting so Close now.

[UtahBeehiver]

Fires after insulation is on but before stucco, this allows the moisture to egress out. Be patience with the firing, if you see steam, you are going to fast too hot. David S suggest you loosely place a tarp or plastic over to oven to monitor condensation, if you see it, the oven is still wet. You can start with a halogen light, then a couple bbq briquettes fires(you can cook a dutch oven meal here), then wood. Have you considered placing a vent in the stucco coat? There are several different ways to do it but Gulf and I use a breather vent and a 1/2" pvc bushing that can be purchased at any auto parts store for under $10.

[TARibs]

So insulated today, 3 layers of blanket over the majority of the Oven, ran out so some of the lower portion of the back only has 2. Stucco is not placed at this point. Casting was completed Sept 1st so it's been sitting drying for about a month and a half. Covered for any inclement weather and air drying on the other days. Lit up 1st fire, few pieces of paper some small sticks and cardboard (you should have seen the spiders come scurrying out :-) , Kept it lit for about an hour. Temp at the top of the dome was about 200-250. The moisture on the sides of the platform was there before I fired it this didn't come out due to the fire. Going to try to fire it every day this week and build up each day. Is 100 increments a good Goal? How many days till I should be building a real decent fire in it that I can cook in? Don't want to jump the gun at all.