Brick and clay pot hybrid

[PsychDoc]

having contemplated dozens of outdoor kitchen ideas, I have ratcheted back. I think/hope that I will have a project that results in an oven that works well, is relatively inexpensive, not overly complex, and quasi movable.i think the picture will give most of the basic information. I will add to this thread as progress occurs- I want to get a first post to hear some feedback and keep me motivated.

[PsychDoc]

Ok, that doesn’t answer a lot of questions. One more picture. The large saucer pot is 25” diameter. The plan is that it will rest on a ring of firebrick splits- with a couple full size for extra stability. The whole thing will be covered with a layer of perlite concrete mix. The tall skinny pot is slated to be the chimney- the base of that pot is 6” then flares to around 9” then tapers to 3”, I’m hoping that will draw.

[Buzard]

I was thinking of trying something similar myself to maybe change my current temporary oven. I will be following

[david s]

I’ve often thought of doing the same, however the suitability of the clay body used will be an unknown factor. The thermal shock characteristics are determined by a number of qualities eg. how open and coarse the body is, temperature the pot has been fired to and the thermal expansion of the materials comprised in the clay body itself. A clay pot like your example uses a clay body suitable for wheel throwing and therefore has different characteristics than one specifically designed designed for high thermal shock resistance. Contrary to popular opinion the higher the clay is fired does not necessarily lead to greater thermal shock resistance. Eg the flameproof cooking pots of West Africa owe their remarkable thermal shock resistance to the clay body texture and the extremely low temperature of firing.
All that aside, your pot may well work ok. You should be able to cut out a door carefully with a diamond blade and angle grinder. An uninsulated pot or chimney will undoubtedly crack so don’t attempt to fire it uninsulated. I think the small 3” foam is too small and you will probably have to cut off the top to get a larger diameter, but see how it goes.

[PsychDoc]

Buzard- stay tuned. It will be a fun build weather it works or not.
david- the big pot will be the key to the build. I didn’t know that about thermal shock, it’s a decent quality pot so we shall see how it goes. If the chimney pot “will” crack that’s a bummer. I might play with it a bit and see- either way it’s neither expensive nor time consuming- but the emotional investment is considerable

[david s]

Buzard- stay tuned. It will be a fun build weather it works or not.
david- the big pot will be the key to the build. I didn’t know that about thermal shock, it’s a decent quality pot so we shall see how it goes. If the chimney pot “will” crack that’s a bummer. I might play with it a bit and see- either way it’s neither expensive nor time consuming- but the emotional investment is considerable

I said an uninsulated chimney will crack. If there is flame anywhere close then the sudden temperature difference between the inside and outside surfaces is too much. A chimney pot on top of a chimney is far enough away from the flame to survive ok. You can insulate around the outside with some vermicrete and it will be fine.

[PsychDoc]

Got a little done on the stand, no pics yet, hopefully this weekend.

I am thinking about the landing and arch. As you can see from the pics the dome isn’t exactly uniform. So as it sits the dome will be 8” off the cooking floor. The dome height is about 14-15” - so we all agree that an opening of 10x16 is good?

Not a small portion of my inspiration comes from this- https://handycrowd.com/building-a-sm...ed-pizza-oven/

[PsychDoc]

So the stand is basically complete. It was a swing set in its former life. I went back and forth trying to decide between ‘new’ wood and recycling things- the recycling is a pain, but it saves a couple bucks and helps prevent catastrophic global climate alteration and societal collapse. The legs are 4x6. It’s quite beefy. But just to make sure I made Toby my pet elephant stand on it for a test. He is not full grown but still quite large. He was calm and seemed quite stable.

[PsychDoc]

Now the stand is actually done. And mobile! Finished with linseed oil- probably a half gallon or more. If an exothermic reaction doesn’t burn it to the earth I should be ok. The wheels are 300lb capacity each, and phumatic- if I let out some air the posts will sit on the ground.
the plan now is to build a temporary platform on top to pour a żhearth. I’m thinking a 1.5 inch slab with maybe 4 inches of perlite mix over that. I think that will be strong enough- do you?

[PsychDoc]

Out of work a little early today so I started on the aforementioned platform. The thought here is that if I build it inverted all the planes should be roughly in the same plane.
I plan to use a big orange box store product for the health- rapid set ‘cement-all’ it claims 9000psi - seems good to me.

[PsychDoc]

My apologies for leaving this without update- here are some pictures

[PsychDoc]

Then pour a floor- I didn’t get a good series of photos here- the form with the straps was holding the pearlcrete base, about 4”

[PsychDoc]

Then started putting bricks together

[PsychDoc]

The outer arch and flue were a confusing mess

[PsychDoc]

Ok, last post to bring us up to current. For a chimney I wanted to vent to the rear, this way I can pull the oven under the pergola without fear of setting it on fire. After considering several alternatives, I settled on a 6” flexible aluminum vent tube. Knowing it may/will erode, I covered the whole thing with refractory mix supported by hardware cloth- and then pearlcrete. My hope is that if/when the aluminum erodes the concrete will remain.
Questions? Comments? Criticism?