36" WF Pompeii Oven in Maryland

[bentedesco]

You keep mentioning soldiers, are you intending to do full soldier or half soldiers? Be aware the full soldiers may require some buttressing due to the outward pressure from the dome where the dome and the top of the soldiers meet. FYI, since you starting to get ready to lay bricks.

Oh! I was originally thinking Full soldiers, however, I don't think I have much room to spare for buttressing.

I'm glad you mentioned this tonight as I can change my design. I was still hoping to get some vertical height in my oven before starting the dome's slope.

I can think of a few ideas, if anyone has suggestions, I've very open to them!

Idea 1: I could do the first course of half bricks on their side, and then lay 2 additional courses of 1/2 bricks vertically (without any slope)
Idea 2: I could lay first 3 courses of 1/2 brick flat with 0 angle before starting to dome my oven.

Would either of these designs give enough structural support?

[bentedesco]

After being out of town for a while, I am back from my hiatus with a status report. Over the past several weeks, I cut my base and began to lay my first 2 courses.

I made a mistake at the dome entrance and needed to remove the "bookends" of the first course as the entryway brick was too thin. I have since rebuilt the bricks at the base of the inner arch to be squared off as shown in the pictures. All in all, the courses are going a lot faster than I thought they would. I've started to get into a rhythm where I will first lay all the bricks at the correct vertical angle (buttering on the bottom) and then I will go back around a second time while the bottom is still green and fill in the gaps in the side joints. Also, I've been very careful to re-wet the bricks with a wet brush when I'm doing this second mortar application.

Also, I found this little tool on amazon to be a godsend to check the vertical angles of each brick when I'm laying my courses:
https://smile.amazon.com/gp/product/...?ie=UTF8&psc=1

[bentedesco]

Lastly, I abandoned my design of stacking 3 courses of bricks straight up before starting to arc the dome as it had an inherent fatal design flaw. While I like the look, I realized that I would run into an issue with the radius still being 18" ~8" off the floor. Using the Pythagorean theorem, if I need an 18" 3-dimensional dome hypotenuse (c), & I have an 8" height (a), my horizontal radius(b) would be ~16.1". If I followed this plan, I would then need to significantly shift the bricks inward with about a 2" overhang to maintain an 18" dome radius. This is definitely the wrong way to go.

(I've attached an illustration of what it would have to look like from a side view)

The only way to avoid this would be to shrink the diameter of the pizza oven floor so I would have an 18" hypotenuse at the top of the three courses of straight stacked 8" bricks) This would then leave me with a ~16.1" radius on the floor of the oven instead of 18" (effectively reducing my oven's surface area from ~1000 in^2 to 800 in^2=) a 20% reduction in cooking surface is too much in my mind.

[rwiegand]

Or make the dome slightly oval rather than a perfect hemisphere by shortening the radius by about 1/8" - 1/4" per course until you get back down to your desired height. Also, if your floor is inside the dome (the preferred conformation, I believe) you will only have two bricks above the floor rather than three.

That's the way I built mine, but I also think it makes essentially no difference in use having the short vertical section around the perimeter. Building another oven I wouldn't bother. This was for a 42" oven, the difference might be more apparent in a smaller oven.

[mk e]

Or move the center of the radius up off the floor, mine is made that way with the center up 4.5". I like the oval idea or a parabola. Or use a larger radius with the centerpoint below the floor and have a corner where the top meets the floor just like the opening arches are normally done. There is nothing magic about a perfect dome other than you get to make all the angles exactly the same which make construction a little easier.

[bentedesco]

Or move the center of the radius up off the floor, mine is made that way with the center up 4.5". I like the oval idea or a parabola. Or use a larger radius with the centerpoint below the floor and have a corner where the top meets the floor just like the opening arches are normally done. There is nothing magic about a perfect dome other than you get to make all the angles exactly the same which make construction a little easier.

Ah, brilliant! I knew there had to be a simple fix!

[UtahBeehiver]

I take it you are taking about the entry arch not the dome.because I can see from the pics the dome courses are using the IT alignment. The arch with vertical walls will be what is called an Axed Arch. There was a recent post where the program for General Tools "angleizer" was posted (it is no longer available from General Tools directly). It will calculate the Axed Arch based on brick size, radius, width, height. Remember the opening arch height needs to be around 63-65% of the dome height. I've used this program several times and it is spot on.

I found the link,

https://web.archive.org/web/20160201...Angel-Izer.zip

[bentedesco]

I take it you are taking about the entry arch not the dome.because I can see from the pics the dome courses are using the IT alignment. The arch with vertical walls will be what is called an Ax Arch. There was a recent post where the program for General Tools "angleizer" was posted (it is no longer available from General Tools directly). It will calculate the Ax Arch based on brick size, radius, width, height. Remember the opening arch height needs to be around 63-65% of the dome height. I've used this program several times and it is spot on.

I found the link,

https://web.archive.org/web/20160201...Angel-Izer.zip

Thank You!! Yes, it will be an Ax Arch. Right now I'm thinking the arch will be 12" tall (18" dome), is 66% within an acceptable margin of error?

[UtahBeehiver]

Close enough for government work..............

Updated

I did notice that the 7.5" dimension may be without joints factored in, assuming brick thickness is 2.5". This may throw your opening ratio off enough to be a concern putting the ratio in the 70s. If this is the case you may have to reduce the 4.5" dimension and arch will be a little flatter. The flatter the arch the more sideward pressure there is and depending on chimney type may require some buttressing.

[bentedesco]

Close enough for government work..............

Updated

I did notice that the 7.5" dimension may be without joints factored in, assuming brick thickness is 2.5". This may throw your opening ratio off enough to be a concern putting the ratio in the 70s. If this is the case you may have to reduce the 4.5" dimension and arch will be a little flatter. The flatter the arch the more sideward pressure there is and depending on chimney type may require some buttressing.

Ah, I see what you mean. Would there be any issue with instead just trimming the angle on the top block if its too high?

[UtahBeehiver]

The anglelizer program calculates the tapering of brick so the mortar joints and taper shape of the brick are consistent. I am not sure what you mean by trimming the angle of the top brick, can't seen the pic, it is too small.

[mk e]

Ah, I see what you mean. Would there be any issue with instead just trimming the angle on the top block if its too high?

The only down side is cosmetic...the 1 row will be thinner when you look in. Nothing functional or structural I can think of.

I think its a bit awkward to do if you've already set the bricks, but if you mark it well you could cut as you've shown in place.

[bentedesco]

Long time no post... I've been waiting to continue construction due to the cold winter we've had up north, however, we're finally into spring and have just a few nights left around 30 degrees. As I am using Heat Stop 50 to mortar my courses, do I need to wait for a full week of above freezing temperatures? I've been worried that if I get 1 night below freezing it could shatter my fresh mortar and I'd loose structural integrity... am I being overly paranoid?


Also, over the fall I got the opportunity to go to Adelaide, AU and visit Maggie Beer's Farm Shop in the Barossa valley. I was able to talk with the chef who built/uses the pizza oven there- what a great guy! He was extremely helpful and encouraging as I was talking about my build and all the great folks here on the the forum. Here are a few pictures of Maggie Beer's pizza oven:

[bentedesco]

Finally finished my dome!

This weekend, I'm hoping I can clean up the inside and then I'm a bit confused as to what my next task should be, right now I'm planning the following order:

1. Construct the entry arch/flue
2. Lay Ceramic Blanket & seal (As I have 2 boxes of ceramic blanket, I plan to insulate the entry arch)
3. Cure the dome (I think it was recently decided that its now best to insulate the dome before curing?) If there is a sticky related to this, I would really appreciate someone dropping a link for me

[UtahBeehiver]

In the Forno Bravo plans there is curing out line in section 17. But a couple newer innovations, start with a halogen light, gets you around 150-75 F. Then a couple firings of charcoal briquettes gets you around 200 F (cook something dutch oven while your at it), then really "small" kindling fires, "don't" throw that extra log on, it can really spike the temp quickly,
then follow FB curing guide. You are looking at about a week. Also current best practice is to insulate but not stucco before curing, David S advocates placing plastic over the oven, if you see condensate form then oven is still wet, if you see steam, going too fast or hot.