36" Pompeii in St Louis

[plastered]

Summary:
I'm 31 yrs old, have never done masonry in my life. I completed this entire build with an 8" angle grinder and a 12" diamond blade on a cheap Ryobi sliding chop saw, which seemed more than sufficient. This thing turned out a million times better and cooler than I could have ever possibly imagined.

Build time: 13 Jun 2020 - 10 Oct 2020

Spent most weekends from June through July building (alone). Took several days off work too, to build. By mid August I was able to use the oven (perfect timing for fall), and the rest of the time was spent on finishing materials. Finishing took me 2 months due to figuring out what to get and laziness, but overall it only took about 2-3 additional "light" weekends of work to finish.

Build cost: ~$4000

I have a spreadsheet where I tracked everything that I may post here someday (PM me if you want to see it). About $400 was spent on tools I didn't have. In summary though the costs were:

-Foundation and block stand: 700
-Hearth: 540
-Floor, Dome, Chimney: 1360
-Finishing (brick façade, counter): 815
-Door: 112

Other fun facts: Bricks were 1.75/brick (used a little less than 180 fire bricks), Refractory mortar 95/bag (4 bags), CaSi blanket and board ~540

Timelapse of my build




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Finally posting the progress of my build. Drilled some weep holes, put down some old tile i found in my basement from previous owners (and some screen I found to keep the bugs out), cut the two layers of CaSi board, and started cutting the keyhole shape for the floor an landing.

Tomorrow I plan to mix up the sand mixture for under the floor.

The only question I have this second, is should I coat the outside of my CaSi with some mortar? Should it be the high temp mortar? I'm mainly looking to 'protect' it I guess since it seems exposed right now, and will be until the dome is done. I remember seeing people coat a ring around it as they start mortaring their first course in place.

Critiques are welcome, and any other advice as always!

[UtahBeehiver]

You can to protect the CaSi from abrasion while you work. I just used the leftover homebrew as I was laying courses.

[plastered]

Leveled the floor, laid out the first course of half soldiers and mortared them into place, I also mortared a little bit of the front landing to keep those in place. Next up I will build an arch form, get my IT going and start the journey upward.

[Chobbs]

Looking great! I will be starting my build soon so watching yours with eagerness!

Which IT did you go for?

[plastered]

Chobbs I'm building mine as we speak -- I just grabbed a caster, a wooden dowel, and a little metal 90 deg angle. I may 'upgrade' to a better one if my 10 dollar one fails me.

[david s]

A length of electrical conduit works pretty well because you can bend it in the middl, which shortens it a bit allowing easy removal from the brick it supports.

[plastered]

A length of electrical conduit works pretty well because you can bend it in the middl, which shortens it a bit allowing easy removal from the brick it supports.

I like the idea, I take it you mean the PVC conduit? For a second I thought you meant the galvanized kind and I was like how the heck do you bend that!

[GreenViews]

I'm wondering if you planned for a door reveal just outside the inner arch so you can close your dome with a door so heat can't get out the chimney? Also, I'm not seeing a heat break at the place of your door. Both of these you can do without, but will not as efficiently hold heat well for cooking after pizza making or retaining heat overnight. Some people just have a small gap just outside their inner arch where the door closes off the dome. You can look up other's designs if you have questions. If the floor is all done, you could perhaps still make a saw cut if you decide you want to. Just a thought.

[plastered]

Thanks GreenViews for reminding me to leave a lip for the door. I was planning on doing that but I completely forgot how I was going to do it. For the heat break, maybe I'll work something in but I wasn't really planning on incorporating anything like that.

[plastered]

Does my IT make sense? Red is origin, yellow lines show that the origin should sit right at the floor (a little offset of the caster). The important thing is that this yellow radius line extends from the origin to exactly halfway up a brick, perpendicular to its surface, right?

[UtahBeehiver]

The offset both horizontal and vertical will affect the dome dimensions as you move up. In addition, if you are doing a tapered inner arch (which I recommend) the same offsets will affect how the dome ties into the arch. It is doable but you will have to adjust the lengths as you move up in courses. From what I can see the IT does not look adjustable.

[plastered]

UtahBeehiver -- I did make it adjustable (hard to see in that pic) because of all the other posts that you suggest to do this . Definitely doing a tapered inner arch too per your recommendations on every thread. When you say offset, is there a visual representation you can show me. In my brain, if the dome is a perfect half sphere, this IT would be fine. Or are you saying in general, any minor offset (from the floor, or in the tool itself) will manifest itself up the dome?

[UtahBeehiver]

Let me make a stab verbally, the vertical pivot point should be at the center of the dome at floor elevation. At floor elevation, the ID of the oven for example, if 36", then at floor level, the oven radius is 18" but as you move up in courses and eventually to the top, the oven radius changes to 18" plus what distance of the pivot point off the floor. The height difference in itself is not an efficiency issue but it does affect how the dome ties into the tapered arch. The tapered arch is fixed and unchanging vs the IT pivot point changes with each course. So you can use the current set up but you need to adjust the length of the IT so the domes ties into the tapered arch efficiently.

[plastered]

UtahBeehiver I think I understand now, how a little bit of either vertical or horizontal offset accumulates. I spent some time in solidworks understanding this. I guess to combat this, for each course I should measure from true center to make sure I maintain the 18" radius, and adjust my IT as I go? I know I've seen a sketch like this before, but now I understand.

(Origin is blue dot, 36" diameter circle, I drew a triangle to simulate the caster shape, arbitrarily offsetting it by 0.66" in the vertical (from floor) and 0.75" from the true center. You can see the 18" IT radius go off course)

[plastered]

I got rid of the caster and am just using a couple eye bolts and hardware. I feel better about this design as the center point is more center (vertically and horizontally), also a tad closer to the oven floor.