Fnbrokens Corner WFO in Canberra, Australia

[fnbroken]

And a scale drawing to make sure it actually fits...

[UtahBeehiver]

It nice to see someone do their homework and research. Looks like you know what you want and need.

A couple comments:
1. As you move up in the dome courses, unless you bevel the bricks, you will end up with what we call an "inverted V" joint. A grinder will work but it is a lot of work, messier, It the budget can swing it look for a used wet saw. Remember, you only need the adjust the inside the dome brick face bevel and taper, not the whole brick.

2. The first brick or partial brick of the internal arch lay flat the. The total inner arch height should be about 13.25" for a 42" oven which you show, but it would slightly more or less. Adjust the width so your arch height is where you need it, within reason ( I guess I can't remember a width rule). I think my inner arch worked out to be 13.125 x 20.25 for a 42" so don't feel you need to be spot on.

3. You might want to consider a weep hole in the hearth floor for any water that may migrate in.

[Isivuba]

And a scale drawing to make sure it actually fits...

Also doing a corner oven but need to get my homework done before I start but yours looks awesome. Will be watching this thread.

[JRPizza]

Greg, I agree with Russell - it's nice to see you are doing some serious planning before you start your build - nothing worse than pouring concrete and realizing you have your dimensions wrong.
Your drawing looks lots like what I did with my corner build. I was looking at your dimensions and between the metric and different brick size vs what I used it is taking me a little time to visualize the details of your oven. If I get a chance in the next day or two I'll try to put your dimensions into my cad program and see if I can give you a couple of sketches.

[fnbroken]

lol...need to present the plans to the Finance Minister...so they cant be half baked!@!

Thanks for the feedback Russell, appreciated - I have been studying closely the inverted 'v' and the 'teardrop' and would really like to avoid them. A new wet saw here is anywhere from 800+ dollars, so not a cheap way to start... Hopefully by the time I get to this stage I have been able to source a cheap, or second hand ($600+), one - or an Australian forum member wouldn't mind loaning theirs out I realise I could get a a fair bit of my money back selling it at the completion of the build - but my wife knows I will probably keep it (like every other tool I have said I would sell).

Question: Where about's do I locate a weep hole - I have not come across this in a design so far? It is highly likely the WFO will be covered at some stage - just hard imagining how it might look at the moment. I was going to include a vent in the top of the dome like yours Russell - seems a pretty sensible idea (especially if the WFO sits idle for any period of time).

JR - thanks for putting some CAD sketches together for me - I have read your thread closely several times now and I think there will be a lot of similarities :/ appreciate your documentation of the build for me to leverage.

I almost started to put imperial measurements next to the metric ones to help everyone out - so confusing sometimes jumping back and forth - I just cant seem to think in fractions I will go back to the previous post and add them in.

Thanks for the comments

[JRPizza]

Greg, here is your hearth with the round parts of your oven. What were you thinking of having for minimum distance between the outside of your dome and the edges of the hearth at the rear (roughly 10 and 2 o'clock)? Let me know and I will fix the dome on the hearth and make a side view to show where the inner arch might go, unless you already have a distance for it, either from the rear of the oven or from the center point. I'll go back and read but don't remember seeing it.

[david s]

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And a scale drawing to make sure it actually fits...

You have a problem here if you build to this plan. The sides of the oven exterior are so close to the wall that you won't be able to access it properly at the base of the dome to finish it off well. It also leaves you with a pretty much useless space in the corner at the back. If you can leave a min of 100 mm between the exterior of the dome and the side walls you'll be glad you did by the time you get to do the last layer.

[fnbroken]

Thanks JR / David - the scale drawing has a gap of about 50mm (2") - happy to go to 100mm if there is a good reason for it - I essentially pushed it as far back into the 10/2 position as I could to allow maximum landing depth. From a usage perspective - this will be no-mans-land going forward so didn't want leave it empty. Why do I need 100mm - the only thing i can think I need to be able to rest here will be the edge of a jig that I will use to ensure the dome stays round....

The inner arch placement occurs where the WFO side of the inner arch intersects the inside diameter of the dome - where the distance is 500mm (19.5") - make sense? Is that how it is positioned? If you look at the drawing, it is the distance labeled as '500'.

[fnbroken]

So a search of weep holes - comes up when a vapor barrier is being proposed between the hearth and insulation to allow any errant water a way to escape. A post by David S also recommends including a slight slope away from the center of the dome to the weep hole(s) to assist in this process. Will add this to my notes for this stage. Thanks for the tip!

Any further ideas or tips? Easier to incorporate them now!

[JRPizza]

Greg, you don't have any rear walls yet, do you? I decided it would be easier to build walls after the oven vs walls first, so I didn't have to deal with obstructions and ended up about 50-60 mm from the edge of my hearth. I still might put some tile on, but there is room for that. When the walls finally go up I'm not going to be going back behind my oven unless I get the itch to clean out the spiders etc that are going to collect there. Like you I wanted to push the dome as far back as possible to have room for a landing without needing to add an extension, and to have the areas immediately to the sides for pans, utensils, and beverages. I did overhang my block stand a little in the front to make the width at the narrow point close to the width of the outside of my arches.

[JRPizza]

Inner arch placement is indeed where the arch meets the dome, but to avoid going out of round you just need to make sure you are intersecting at the top of your arch. Folks that put the arch too far fore or aft have to deviate from round to meet the arch.
If you look at my post #28 of this thread "https://community.fornobravo.com/forum/pizza-oven-design-and-installation/getting-started/355718-hearth-size/page2" I showed how I can move my TDC brick fore and aft and still meet the dome, so there isn't just a single right dimension (I don't think). I used your door height and it looks like I would put the forward face of your inner arch at 620mm from oven centerline which would maximize your cooking floor, deep the dome round, and give you a nice arch protrusion. I'll work on a plan view with that distance and your other dimensions to see how that looks. You are going to want to make a full size (cardboard) layout eventually but these dimensions might help.

[JRPizza]

OK, I'm running out of free time today - here is a plan view I made using the above inner arch distance and your measurements. I didn't bother laying out the heat break, but that is only a half inch and really is in the noise. You could move the inner arch back if you wanted - I showed a protrusion of about ~64 mm for the inner arch at the bottom of the dome, so you could move it back up to about 50mm and still have room for your heat break overlap, but that is cutting it close. What the picture also shows is you might want to extend the front of your slab a little like I did if you are planning on putting on any decorative facing, or just want a little more room. I think I have the dome about 45mm from the edges in the rear, so the front is going to be tight. I also uploaded an axometric view just for grins. I would be more than happy to give you a copy of the file if you want to play around with FreeCad - it's nice to be able to move things around on your own and the price is right!

[fnbroken]

Thanks heaps JR - looking good, appreciate the guidance.

I will need to pour the landing and surround at some point (to cover the vermicrete etc etc) - so when i'm it forming up making it extend further in front shouldn't be a problem. I will add extra rebar to the front and cover it to ensure I have sufficient strength there - or I recall someone using what looked like large bolts sunk into the initial hearth to secure it by. Given it wont have a great deal of weight on it, should be ok - plus keep as much headroom on the stand (I'm 6'5" tall).

Importantly, all the main components fit on this size hearth. That said, going an extra half a besser block in each direction (200mm, 8") would give me a lot more room to move? Will have to measure up how much space I have in the backyard to accommodate it.

Also, by the time I get to this point, I will have a better idea of how much room I would like in front of the outer vent (I have no idea - never seen one of these in real life!)

The first CAD of the arch intersecting the dome at the top is definitely something I missed when placing the arch. Was it the CAD program that recommended the 620mm distance? I was kinda working backwards - with the brick to extend out 50mm at the base....that it would just 'work out' when I got to the top by moving the bricks in or out as required. It actually needs to intersect the inner dome/inner arch at 345mm off the floor! Which logically is further into the WFO - roughly 100mm in fact. Interesting...

[fnbroken]

So something that has been 'bugging' me for a little while now - here in Oz, the standard firebrick is 230x115x75 or 9"x4.5"x3.0" - this size gives me 9 courses using Deejayoh calculator on a 42" dome.

Most builds on the forum however use a 2.5" high brick - or 63mm - resulting in a several more courses - and a much neater finish (albeit a lot more cuts!).

Another standard in Aust is a 2.0" brick, or 50mm - making 15 courses! Would I be better of going with this size brick?

[UtahBeehiver]

Either/Or. I used 3" thick brick that was even odder size 5.875" wide x 9" so any brick size can work up to a reasonable point.. I would go with the best price for the quality. You being in Aussie land, brick and material cost are a crazy insane cost factor.