did i mess up?

[pepe]

Hi, I am in the final stages of my oven build, I decided to go against all odds and built a 70 cm, 1/3 cut firebricks (results a 7x6x11 brick, and a 7 cm deep dome) mortared with beautiful purple homebrew (used white Portland and the dust from the cutting of the bricks). Donīt worry, I will buttress when closing the dome.

I believe that by trying to maximize the minimum space used, I did not leave enough clearance for the flue. Any recommendations? I don’t think I can safely get it to lay in place because of how I made the dome. I am planning on covering with a blanket. Here are some pictures and I would be eternally grateful for any ideas.

My instinct is to sort of make a semi beaver/squirrel tail and send it a few cm back (my fear is that even though the vent is not too heavy, it is measuring about 1 meter SS will fall forward).

Thanks.


EDIT: The keystone at the entry arch is the mot outer part of the dome.

[Kvanbael]

(Disclaimer, no expert myself). How will that concrete heart stay suspended? I suspect the plywood is only temporary. If you were still planning a support structure, then maybe you could extend that to support both sides of the flue.

Alternatively, you could angle-grind the top of your entry arch. But then you’ll need an oddly shaped door to close off the dome.

lastly, you could have a shallow flue as a custom stainless steel construction.

[pepe]

(Disclaimer, no expert myself). How will that concrete heart stay suspended? I suspect the plywood is only temporary. If you were still planning a support structure, then maybe you could extend that to support both sides of the flue.

Alternatively, you could angle-grind the top of your entry arch. But then you’ll need an oddly shaped door to close off the dome.

lastly, you could have a shallow flue as a custom stainless steel construction.

1. The hearth will stay suspended because it is reinforced rebar into the wall and on the sides, the whole table is anchored to 2 walls. Sadly I canīt extend it anymore, that is the absolute limit that the area can handle. I know it looks iffy, but most builds on the site are LEGIT TANKS.

2. I like the shallow flue idea, I canīt seem to find examples, do you know of a build that does this?

[Kvanbael]

Here's a post where I installed my steel flue.
https://community.fornobravo.com/for...949#post424949

Here's another thread with a similar idea. Not sure if it was executed:
https://community.fornobravo.com/for...llery-in-steel

[pepe]

Here's a post where I installed my steel flue.
https://community.fornobravo.com/for...949#post424949

Here's another thread with a similar idea. Not sure if it was executed:
https://community.fornobravo.com/for...llery-in-steel

That is actually pretty cool, yourīs is a great build, thanks a lot! I see I was doing my search the wrong way, googleing the forum gives me a couple of good results.

[pepe]

(Disclaimer, no expert myself). How will that concrete heart stay suspended? I suspect the plywood is only temporary. If you were still planning a support structure, then maybe you could extend that to support both sides of the flue.

Alternatively, you could angle-grind the top of your entry arch. But then you’ll need an oddly shaped door to close off the dome.

lastly, you could have a shallow flue as a custom stainless steel construction.

Do you tihnk there is a way to cut the 2 inches I left of brick on the entry walls? I thought they would help anchor my flue, but now I am thinking I dint have enough space for a heat break gap and I also need to cut the last brick on the floor even more to have enough space to but on an inch of insulation and stop it from being a huge raidator?

Am I being paranoid?

[Kvanbael]

Many ovens out there without a heat break and super performance and happy owners. Heat travels slowly through brick. My 2c: You are already challenged with little space, don’t add extra requirements.

[pepe]

Many ovens out there without a heat break and super performance and happy owners. Heat travels slowly through brick. My 2c: You are already challenged with little space, don’t add extra requirements.

I think you are correct, I thought I was being paranoid!

I believe I only have one new and hopefully last problem I oversaw, my insulation, My Ceramic Blanket hits/touches directly my non combustible wall, there is about a 3x3 inch square that has no space. I donīt have enough space to render over that back part. Can this be a problem/hazard? I could probably break the rock tiles off the wall but would prefer not to.

CB thickness as follow: 2 inches of blanket on the back, 3 inches on the sides, and about 4 on top. I did not want to save and store any unused blanket.

[Kvanbael]

Unless those electric wires run straight behind that patch, I'd say not immediately hazardous. The morning after a long pizza party, you can expect more heat to leak out of that patch... only to be quickly dissipated onto this massive wall. So probably not the end of the world. But why not break out a few rock tiles from the back and get an extra inch? Sounds like your render will have to transition into the back-wall anyway, allowing you to cover up the damage.

[pepe]

I did not share my almost finished oven, have been using it for almost a year! But I am not sure everything is going as planned. Recently small bits and pieces of the mortar have been showing up on the floor, probably from wood hitting the ceiling and occasional dusting after a firing. I am just worried that the mortar is not hard, it literally turns to dust. Is this expected or my mix did not set correctly, and my structure might fail?

[Sixto]

Can you share what recipe you used for your homebrew? (how many parts of Portland, Sand, (or brick dust) Lime and Clay?) Also, describe how much water you used, and whether the mix was runny or stiff?

[pepe]

Can you share what recipe you used for your homebrew? (how many parts of Portland, Sand, (or brick dust) Lime and Clay?) Also, describe how much water you used, and whether the mix was runny or stiff?

I went with the homebrew mix, 3:1:1:1 but I also sometimes added brick dust whenever I had around, never really measured it. But I am sure most of the time it was never actually even close to a "1 part" of the mix. I let it be almost too runny but managable, and I really wet the bricks (mix was defenitley not stiff).

Maybe I shouldnīt worry and its just dried up mix that didnt bind to anything?