Planning to build a tiny oven

[Fvsion]

Hi everyone,

This is my very first post on here but I've lingered for longer, actually a little too long. I've been reading a lot about building ovens and what not and after convincing myself to get off my rear and do something, at least, I have decided that I want to build an oven. To get me started, though, I need to ask questions first.

I am planning on building a very small oven (tiny compared to the specified size on this website) and after searching online for a design, I stumbled upon a company that makes portable pizza ovens (not sure if I'm allowed to say the company name on here). So I looked into their design and their initial ones but was only able to find pictures.

The reason why I would like to build something similar is because of the size (I am a modern day nomad, I don't stay in one place for too long) and because I feel like building something small won't overwhelm me.

So, I will tell yous about my thoughts and would greatly appreciate any feedback/tips/suggestions.

This will be how I would like it to look:


It's really small but it's fine as I only want to cook a 12-inch pizza in it. I was thinking about two things: wood-fired and gas-fired. I know, I've read all of the things that people on here said about not messing with gas but from where I live, gas would be a very inexpensive way to fire this little oven.

If I am going with wood, it'll be easy for me to buy a little, camping wood stove, cut a hole at the rear of the oven floor and fit it at the bottom. I may have to think about building a chimney for the design, though.

If I am going with gas, I'll do the same: cut a hole at rear of the oven floor, and fit a single gas burner stove. The problem with it if it is okay to do this - I've read somewhere on here how the gas burners aren't build for low oxygen environment, etc. But since there is a big hole at the front, would that be okay? I will not be covering the front anyway.

My design and build will slightly be thicker as I will be using firebricks and rockwool instead of just cement as seen on the photo above.

Please let me know what yous think, I'd love to hear your thoughts.

Cheers,

Fvsion

[Fizz]

Just a thought on gas burners, I´ve seen some youtube videos of people melting metal or sand (+other stuff) to make glass, and they often use makeshift kilns or furnaces and a burner that they tuck in there tightly to not let out any heat ... so there has to be options out there that does not need air, like a gas stove does ...

[Fvsion]

Just a thought on gas burners, I´ve seen some youtube videos of people melting metal or sand (+other stuff) to make glass, and they often use makeshift kilns or furnaces and a burner that they tuck in there tightly to not let out any heat ... so there has to be options out there that does not need air, like a gas stove does ...

Thanks Fizz, I'll look into that. Can you link some of those videos you've seen? Cheers - Fvsion

[Fizz]

http://www.instructables.com/id/How-...-Forge-Burner/

Could probably be useful...

[Fvsion]

http://www.instructables.com/id/How-...-Forge-Burner/

Could probably be useful...

That's very useful! Found a lot of info that I need and got me to consider the torch option. Thanks Fizz, I appreciate the help mate!

[Fvsion]

Hi fellas, so I wasn't able to get around to building my planned little oven due to many, many things. Anyway, I am now planning to pick it up where I left off.

I have been planning to make something similar to this:


Only I have been thinking about putting it above a typical low-pressure gas burner. I was hoping to just cut a hole at the back of the oven so that it loosely fits a burner.

Having looked around the internet, I stumbled upon the pizza hacker and found out the he just modified his 22" Weber grill and made it into an oven:


He mentioned on this video (https://www.youtube.com/watch?time_c...&v=RLC-SIGpZkE) that he made the dome using only refractory cement and perlite.

My question now is, what do you think the ratio of his cast oven is? Is it 1:1 perlite + refractory cement?

Do you have suggestions as far as the materials I can use and their ratios?

I am planning to have a sheet metal cut into a good size and then put firebricks as the cooking surface and build a dome on top of it.

Any help/suggestion would be appreciate.

Cheers!

Fvsion

[Rocko Bonaparte]

I just clicked on the thread on a whim and saw the last post there. Just attach photos using the forum's only photo attachment stuff and you shouldn't run into bandwidth problems. We can't see the pictures.

I would look in the "Other Oven Types" forum and generally search for "refractory cast." There are a lot of recipes out there. This thread, for example, starts to go into many possibilities:
https://community.fornobravo.com/for...y-casting-oven

You can ask a hundred times and get a hundred answers.

I can't speak with 100% experience on the topic since I have never casted one. I did do a pseudo-cob oven using pottery clay and pottery sand. If this oven has to be portable, then you will want to look into your perlite mix would do, but that stuff is actually insulation. Furthermore, portland cement in itself is not very strong against heating cycles. You will be relying a lot more on the flame doing the work for you, and I don't think you'll necessarily get the effect you want--especially if you're not using refractory materials on the floor to cook the bottom. They generally cast a cement/perlite mix around the outside to keep the heat in.

The mixes that go into things like sand, clay, or proprietary materials are trying to soak up heat and evenly dole it out, but they're going to be heavy. Portland cement by itself isn't the best structural binder for such heat but it's just so accessible compared to proprietary materials. Clay can take the heat and can be shaped, but it isn't good against water

[Fizz]

I think you should take a look at Uuni (https://uuni.net/products/uuni-3) if small and portable are important features for your pizzamaking.

When building my own oven I realised that all things that make WFOs good are 1: heavy, or 2: expensive, or a combination of both.

[Fvsion]

I just clicked on the thread on a whim and saw the last post there. Just attach photos using the forum's only photo attachment stuff and you shouldn't run into bandwidth problems. We can't see the pictures.

I would look in the "Other Oven Types" forum and generally search for "refractory cast." There are a lot of recipes out there. This thread, for example, starts to go into many possibilities:
https://community.fornobravo.com/for...y-casting-oven

You can ask a hundred times and get a hundred answers.

I can't speak with 100% experience on the topic since I have never casted one. I did do a pseudo-cob oven using pottery clay and pottery sand. If this oven has to be portable, then you will want to look into your perlite mix would do, but that stuff is actually insulation. Furthermore, portland cement in itself is not very strong against heating cycles. You will be relying a lot more on the flame doing the work for you, and I don't think you'll necessarily get the effect you want--especially if you're not using refractory materials on the floor to cook the bottom. They generally cast a cement/perlite mix around the outside to keep the heat in.

The mixes that go into things like sand, clay, or proprietary materials are trying to soak up heat and evenly dole it out, but they're going to be heavy. Portland cement by itself isn't the best structural binder for such heat but it's just so accessible compared to proprietary materials. Clay can take the heat and can be shaped, but it isn't good against water

Hi Rocko,

Thanks for pointing me to the right direction. The pictures are now up so you can see what I am trying to envision. My motive is basically only weekend pizza.

Cheers,

Fvsion

[Fvsion]

I think you should take a look at Uuni (https://uuni.net/products/uuni-3) if small and portable are important features for your pizzamaking.

When building my own oven I realised that all things that make WFOs good are 1: heavy, or 2: expensive, or a combination of both.

Hi Fizz,

You are right but I just can't justify spending that much for weekend pizzas yet. Maybe if I have a lot of extra cash I'll buy either Uuni 3 or Roccbox.

Cheers,

Fvsion

[Rocko Bonaparte]

Hmmm portable do you anticipate it needs to be?

[Fvsion]

Hmmm portable do you anticipate it needs to be?

Hi Rocko,

I hope it's portable but I don't mind if it's heavy. Basically, I need something I can easily move around. Not really looking into cooking multiple pizzas at once. Been reading and watching a lot and I think I have an idea of how I want to build it. Keyword being think. lol. Not 100% sure how I'm going to go about it though.

One of the challenges I see is the mix. I see people using many different ratios and I can't decide which to follow.

Cheers,

JC

[BenKeith]

I probably should not be trying to answer questions because I'm no expert on this stuff and I am building my first oven now, but from what I have learned doing my research, it does not make since to build what you want when it's probably much cheaper just to buy something.
Gas burners suitable for a pizza oven are very expensive. Forge burners an not practical because they are designed to put a lot of heat in a small area. You need a burner that's going to distribute it's heat over a larger area fairly evenly. Most cheap BBQ style burners are not designed to operate inside an enclosed space that's over 600-700 degrees. Without a properly designed burner, you could easily be creating a bomb.
For a mini oven, I would think efficiency would be critical. None of these homebrew refractories are efficient and create a huge amount of bulk to be able to work. The most efficient materials like glass fiber mat, insulating fire brick and high quality castable, dense, refractory or refractory bricks are expensive also, and they are heavy. Then you have to cost of materials needed just to build molds and other stuff required to fabricate the thing.
I'm building my own because I'm building a larger, 36" oven. To buy a quality oven that size like FB makes, by the time you are done with the stand and have in completely installed is "several" thousand dollars. Since I had a couple thousand dollars worth of the needed materials on hand, and the tools and equipment, I opted to build my own, and it's still costing over a thousand, which most of that has goine into building the stand, concrete and stucco. Building the oven has cost me very little, less than $200, not counting what I've spent on materials for molds etc..

[Rocko Bonaparte]

Yeah I can't comment on using a gas burner in this case either. My own speculation is the rest of the grill may be the problem--particularly the paint or powder coating. It would seem odd that this stuff would suffer, but something that can take 500-600F just fine might start flaking its skin at a sustained 900F. As for the other bits, it gets trickier the smaller and lighter you want to make this.

I'll suggest something and you can probably tell me it sounds similar to what you already saw. It looks similar to the video. Assuming a kettle with a burner on the bottom, I'd do an experiment where I got the thinner firebricks--not the 2.5x4.5x9 bricks, but rather then ones that are 1.25" wide or whatever. Suspend them over the floor, and probably just on the existing grates. Build a perimeter by stacking cut halves of these bricks around with just an opening on one side. Cast some tiles of light perlcrete or something; maybe mix some stucco fiber in so they stay together. They will get crumbly with use, but they're so light and cheap that it doesn't really matter. Use those tiles to insulate these bricks a little bit. Lay another grate on top with a layer of thin bricks and insulating tiles. Make sure air can get into the top. Mount the lid of this kettle with the handle removed so you have one/two holes. This will let excess gas escape if it's building up and keep you from burning off your face.

It's basically a firebrick cylinder open on one side.

In this way, you can play around with the heavy materials without having to keep it in one unit that might get too big to move around, and you can tweak things to see what works before committing to something. What might just happen is this works fine for years until you eventually just build a big one.

[BenKeith]

Just get you a big green egg. My son has on of the large ones and luvs the thing. He claims there are a couple of mods people do to them and use them for a pizza oven. I looked at one like his, but for $1500 bucks for the one like he has (not saying you need a $1500 one) I can build my oven and do everything it can do and then some.
As for suggestions on how to build a mini pizza oven, I wouldn't know. Other than what I've read about those alternate, home brew insulations and refractories, and knowing that was not what I wanted. I don't know anything about using them. A two inch layer of #8 Max Wool will probably insulate better than a 10" of that home brew stuff.