Make pizza with a plasma cutter, a backhoe and a pile of mud!

Step 15 Baking

I have to fire the oven for about two hours to get it up to temp: I fire it until the soot burns off the ceiling, then for about another half an hour, and then it's hot enough for pizza-- somewhere above 800 degrees. I push the coals off to the side with a weed-whip, then mop the exposed floor with a damp rag wrapped around the weed-whip. Then we're ready to bake.

Comments

[beckenham]

Hello Fritz, Wonderful instructions. About the foundation - did you go below the frost layer, or is that simply a pad? Thanks.

[beckenham]

Sorry - I see that you poured a slab. Have you been through a winter yet? I'm wondering how it's holding up.

[fritz.bogott]

It's just a pad, on about a foot of gravel. Definitely not best-practice. We figured that the consequences of a big ol' crack through the concrete pad just weren't severe enough to justify the effort of a properly-built foundation. If the base were mortared or if the oven were brick we would have made a different calculation. But we've been through two Minnesota winters with it and it looks like new.

[PaddyKevin]

I am wondering if concrete pavers instead of a slab over the bed of gravel that you descibed would be the easiest way to go and not have to worry about cracks

[PaddyKevin]

Greetings.  I have questions if you do not mind.  First, if, like me, metal work is not going to be practical, what would you suggest the doors be made out of?

Second, I was wondering if you thought of using the bottom area as a bbq smoker, with a tad of alteration I suppose

Kevin
Buffalo, NY

[fritz.bogott]

Hi Kevin,

The Denzer book (which you should buy because it's great) suggests making a door out of adobe or wood.  You may need to soak a wooden door in water for a few hours before using it so it doesn't scorch too badly and so it contributes some steam.  Anything would work though, really.  A stone or concrete paver if it's not too heavy?

As far as metalwork goes: I usually find that the most fun part of any project is hunting around my county for people who know the trades I'm missing and hiring/befriending them.  You meet new people and learn a lot, and it expands your sense of what you and your growing crew can build next time.

You can totally use the oven as a barbecue pit.  Just keep a slow fire going off to one side and throw some soaked chips on the fire from time to time.

It's fashionable among molecular gastronomes and Make Magazine readers to use a computer-controlled blower to keep the pit's internal temperature as stable as possible.  <a href="http://www.mikezed.com/">Mikezed</a>, whom I met at Maker Faire SF 2008, encouraged me to try that with a cob oven.  I haven't gotten around to it, but perhaps you could pave the way?

-Fritz

[PaddyKevin]

Thanks so much.  That temperature controlled blower sounds good, but I like things as simple as possible.  Living in a similar climate as you, I am concerned with having to cover the oven with a tarp, but I suppose a protective wood structure around it after it is built might be neat, especially as you say if it is designed to allow moisture to leave

[fritz.bogott]

The canonical thing to do is to build an A-frame roof fairly tight over the oven, like this:

(Image CC-BY-NC-ND by kathryn_goddard1)

[Rouxyou]

I have been wanting an oven in my yard for the last two years much was total material cost?. LIving in Florida, there is an issue with clay and mud.

[koyaniskatzy]

I'm in Florida too and been recently working out in the yard. I started digging to install a pond and about 3 ft down the way the soil turned red. Would that be the clay layer? It doesn't crumble easily, and the clumps look like actual rocks. Rouxyou: Have you found more info? I'm planning on building an outdoor grill and an oven would be great since I would also like to learn how to make my own bread. Great Instructable!!!

[Rouxyou]

I bought the book Build your own Earth Oven by kiko denzer. Thats as far as I got.

[fritz.bogott]

Preheating a pizza stone (for pizza or flatbread) or a cloche or a dutch oven (for bread) in a gas grill turned all the way up works great too. Same principle as a brick or earth oven, and very similar results.

[fritz.bogott]

The Denzer book has a whole section on testing your soil. Great book!

[koyaniskatzy]

thanks, would it be too much too ask for the name of the book? My library catalog didn't pick any Denzer, and I may have to request it on swaptree. thanks again!

[fritz.bogott]

It's on the first step of the instructable, with a link to a bunch of places that stock it.

[fritz.bogott]

If you build one like in the Denzer book, you'll probably come in between $100 and $200. If you add a bunch of extras like I did, you'll end up closer to $500 - $600. But get the Denzer book. It's great!

[materials]

fritz: i was thinking of using high fired clay that i can buy from a pottery shop here-with your expertise knowledge can i do that?instead of the dig & find and add? for my lst layer over the sand mold then insulate with paper and again use more for the outer insulating layer and place some brick , tile or metal design pieces.......will this have to have a roof for mid wisconsin weather-alot of question i know -have to wait for order on denzer book and want to get materials purchased-thank you bev

[fritz.bogott]

I completely love the Denzer book and Kiko's general outlook on life. You should buy it in any case as an anti-negativity touchstone of how awesome people can be sometimes. (Plus it will help give you the information and confidence you'll need to build your oven.) Purchased potter's clay will work fine (it's the same stuff after all) but you'll need a LOT. I don't understand what you mean about "insulate with paper." Can you clarify that? The third, outermost layer, is for looks not insulation. You want something flameproof and that breathes enough so that steam from your bread doesn't condense on the inside of the decorative layer and turn your insulation and thermal-mass layers to mud. If you were going to use metal or concrete or tile or something you'd have to arrange for adequate ventilation between the oven and any relatively-airtight decorative and/or weatherproof layers. Alan Scott-style ovens are like that: If I remember correctly, they have a weatherproof cement-board shelter built over the masonry, but not built down tight to it. I live in Northfield, MN and I keep a tarp over mine all the time whenever it's not in use. Rain would turn the adobe back into mud. The same would be true for un-fired clay. Clay with absolutely no organic matter in it would probably hold up better in the rain than subsoil with some organic matter, but not well enough to go roofless and tarpless. Keep the questions coming. I love to talk about ovens. -Fritz

[sjzabel]

That was a fantastic Instructable Fritz! The combination of detailed instructions, excellent pictures make it very easy to follow :) I also like that you left in the names of friends and family as well as the random finds and happenings that make projects like this worth doing. Thank you for the inspiration! Stephen