Garbage Can and Flower Pot Tandoor Oven

SAFETY UPDATE: You should not do this with a galvanized can! If something goes wrong (too much airflow, too little insulation) the outer can could exceed 1,000DegF and the zinc (that's the "galvanized" part) could vaporize into a toxic gas! Avoid galvanized! Thank you vigilant commenters!

I love to eat Indian and Central Asian naan.

My genius friend Dave Bauer of the Farm and Sparrow bakery near Asheville, NC sent me this video a while ago and I started baking naan immediately. (There is no chance I'll ever be as cool or as skillful as the woman in the video, but there's no reason not to trail distantly behind her.)

I have been baking naan on a pizza stone in my electric oven (turned up as high as the oven will go) for a year or so with decent results. When I saw John List's flower pot tandoor I knew I had to build one.

It took fifty bucks and a couple of hours, and it works! It will take a while to get control of shaping, heating and timing, but the (homely) results are already delicious!

Whether or not you build this oven, you should run out and buy Flatbreads and Flavors by Jeffrey Alford and Naomi Duguid because it will immediately make you a happier person.

-Fritz
http://knaveoftarts.com

Step 1: Garbage Can

Your basic brand-new thirty gallon galvanized garbage can. This is just an arbitrary fireproof container and has no role in cooking.

Comments

[SaveOurSkills]

In the photo with the drum is that just pea gravel or is that vermiculite?

[fritz.bogott]

It's vermiculite, which is a really good thermal insulator when dry but absorbs water like a sonofagun, so you need to watch that. (Ask me how I know.)

[bp123]

What did you do to protect this from rain? I was thinking about keeping mine covered during non-use with the lid that comes with the drum. And keeping it inside the garage during the winter. You think that wud deter cracking? Thanks again

[bp123]

Using your design, Im gonna be using a 30 gal steel drum too but it still has paint on the outside, not heat resistant. How hot does the outside of your can get? Do you think I should strip the paint or do you think it wont get hot enough to melt it? Thanks

[fritz.bogott]

If you insulate all around the inner pot, the drum shouldn't get very hot at all-- except possibly where the air-intake pipe contacts it, where I could believe you might burn off some paint.

More importantly though: Several commenters have warned me to beware of lead-bearing flowerpots. It's probably possible to buy a test kit for this.

[bp123]

Isn't it safe to assume that pots that are made today will not have lead?

[fritz.bogott]

I don't think that's a safe assumption. I found this just now:

"Before getting started: Check to see if the container is marked as “Lead Free” or “Safe for Food”, if not marked and in doubt, check with a lead testing kit."
http://tipnut.com/baking-flower-pots/

[bp123]

Actually I'm seeing some sites talking about lead in terracotta. I guess I will ask the company and do the test myself

[fritz.bogott]

Yes, I think that's a good idea.

[bp123]

I called a company called Deroma which sells terracotta pots to Home Depot. No lead usage in their pots.

[jallan5]

I was thinking of doing this, but there are also toxicity issues with commercially made clay pots as well. One common source is China where lead is an issue. You should look for some kind of food grade clay pots, like Tagine and rice cookers. These are more expensive, but worth it not to have lead leeching into your food.

[ferrous]

You should probably know that you should completely burn off the galvanization from the can before you actually cook in it. If you see that thick, curling white smoke coming from the galvanised parts, don't inhale it! It's poison. This is why welders dont like to work with galvanised metal, and neither should cooks ;)

[justafew]

I would love to get my hands on 2-3 un-galvanised cans for "turkey in a can" right now we are using a very large terracotta pot but it limits the size of the bird we can cook. Can find untainted cans at the hardware store...any thoughts?

[jackhg]

call a galvanizer, who actually dips the steel buckets, maybe they can tell you where to get the cans, they might even have some rusted ones

[chuckr44]

Get a painted bucket at Big Lots, then burn off the paint (build a bon fire around and in it). How's that? But that's only a summer item and they are running out fast.

[fritz.bogott]

I checked what the pit-barbecue folks do. They go to their nearest oil-drum factory and buy a brand-new unused drum. Ask the people at the factory which drum is appropriate for making a grill. I went and bought a thirty-gallon open-head drum today at Consolidated Containers in Minneapolis, http://containerexperts.com. Any big city should have a similar place.

[paddlesport]

Zinc melts at approx. 900 F. Vaporizes at approx. 1200 F. Not likely to occur in any cooking process I am aware of. Bake on!

[fritz.bogott]

I re-thought this from a failure-mode-analysis perspective. While I know empirically that it hasn't gotten that hot so far, I agree that it certainly could, and that the failure condition is unacceptable (and totally unnecessary). I have added a big safety banner to the front page of the instructable and I'm planning to rebuild inside a non-galvanized container. Thank you very much for the safety info.

[ferrous]

Although, I forgot to add that I really like your design otherwise :)

[ferrous]

Actually, there are alot of wood fired pizza ovens that can get to 1000 F and beyond. Its really quite easy for the occasional hot-spot to reach those temperatures. I wouldn't personally use a zinc plated can, is all. That stuff's nasty.

[fritz.bogott]

Yes, I know. The way I built it, the galvanized can does not get above 100DegF because of all the insulation.

[Ali_Jay]

You mention about not using a galvanised steel container.

I have an old galvanised purpose build garden incinerator. Would it be safe to use such a product? I'd expect this to be a safe product to use, but would like your insight.

[fritz.bogott]

I don't have any independent knowledge on the subject. Other commenters (and also my machinist friend) have told me that you should never use galvanized for anything high-temperature. Of course, if that's the case, then no such a thing as a galvanized incinerator should exist. No idea how to resolve the contradiction, I'm afraid. I would err on the side of caution.

[hamstanz]

how would you go about emptying the ash ?

[fritz.bogott]

Big pieces out the top, small pieces and dust out the pipe at the bottom.

[handyman05]

I think that this is an amazing project and shows an amazing amount ingenuity and creativity. However, could I not just get a baking stone, put it on a grill, and bake my naan that way? I have heard of people doing it that way if they did not have the Tandoor oven or the obvious creativity that you display here. What are your thought about doing that vs. using your method? Do you think that there will be a flavor difference?

[fritz.bogott]

> I think that this is an amazing project and shows an amazing amount ingenuity and creativity.

I can't take credit. It's John List's design.

> could I not just get a baking stone, put it on a grill, and bake my naan that way?

Absolutely. I do that at least weekly. You want to use a fairly thick baking stone or risk having it shatter. (Ask me how I know this.) I use the same trick for pizza and focaccia. For loaf breads I use a preheated clay dome over the preheated stone: 9/1/2010 Sourdough

> Do you think that there will be a flavor difference?

There are a bunch of subtle differences due to intensity of heat, distance to heat, direction of heat and ratio of convective vs. radiant heat, but the convenience of the stone-on-grill method makes it superior unless you have plenty of time or are showing off for a crowd.

For a single batch of naan, I use 3c all-purpose flour, small handful kosher salt, small handful yeast, mix that all up and then pour in buttermilk while stirring until it forms a nice wet but not quite sticky dough. I knead it well, then let it double, then roll out tangerine-sized rounds to a generous 1/4" thick on baking parchment, poke a bunch of holes in the center of each loaf with a fork, and transfer the dough-with-parchment to the stone using a cookie sheet as a peel. Takes a couple of minutes to bake on a really hot preheated stone, longer on a cooler or poorly preheated stone. I never get good blistering on the grill because most of the heat is coming from below. The tandoor, stone-under-broiler and cast-iron-skillet-under-broiler methods give you better blistering. Sometimes I brush the finished loaves with melted butter or ghee.

[handyman05]

Thanks. I will keep that in mind the next time that I am trying to make some naan. There is a Himalayan resturant that I go to and they have very tasty naan. Also, thanks for the way that you answered my questions. Helped my brain absorb the information better. Happy naaning? I guess baking would be better, but since we were all referring to naan and how to make it using this kind of oven, naaning sounded cooler.

[Rajabbek]

Good project! I live in Uzbekistan, and yet no where did not see that someone had tried to create such minitandyr. Wizards, in preparing the clay for tandyr add back down from head rushes. Tandoor should not be conical and slightly oval and narrowed at the neck. Landscape with a throat tandyr set up mainly Turkmen. And Uzbekistan

[fritz.bogott]

Hi Rajabbek! I'm excited to have an Uzbek reader, since it was an Uzbek tandyr that started all this. (If you follow the video link in my introduction, it links to a video about Uzbek non.) I need a chekich, though. I don't suppose I can send you something in exchange for a couple of chekich? What does the down do to the clay?

[Rajabbek]

Hello Thank you for your feedback on my comment. I must confess that I do not speak English, and translate the texts of comments from Russian into English using Google translator. Despite this I really liked your project. As chekich, I do not understand what it is, can you know the name of the Uzbek? On the Uzbek is a verb Chekmok, which means smoke.

[fritz.bogott]

A chekich is one of these:

I could make one, but I would love one from Uzbekistan, if we can work out a barter arrangement.

[macrumpton]

It seems like you could sidestep the problems of the toxic galvanized metal by just making your own enclosure out of some sheet metal. Since it does not get that hot I think using aluminum flashing (available at most hardware stores) and a few nuts and bolts or pop rivets would give you a perfect metal tube that you could size exactly to the flowerpot.

[fritz.bogott]

Yes, that would work very nicely.

[macrumpton]

When I read the instructable again I was struck by the cost of the metal can. To get a 10' roll of aluminum flashing 2' wide is about $15 in the expensive hardware store near me, and if you could find a printer that is tossing aluminum printing plates you could get it for free. Another cool thing about using the sheet metal is that you could make your container other shapes besides a cylinder, so if you wanted the top of your oven to have some counter space you could make it a truncated cone (point down).

[fritz.bogott]

Good idea!

[robertblacksmith]

one of my tandoori cook books,which of course i can't find, opening chapter is on the history and making of tandooris.in India they don't turn them on a wheel but start them as a flat sheet of thick river clay which they roll into a tube wet the edges and work the clay tell there is no seam . stand it up right and work the top of the tube tell i forms a cone shaped top. all being made at the craftsman's shop were open topped. it allso was interesting that the inventory on the shelves behind them. many clay oven alone but half where in metal barrels. also because my head is full of useless information. lead was used as a coloring agent in pottery glaze before the danger was found and was band in most places.

[fritz.bogott]

*One* of your tandoori cookbooks? I'd like to visit your library! If you figure out the author or title of that book, let me know so I can track down a copy!

[robertblacksmith]

"Tandoor: The Great Indian Barbecue " by Ranjit Rai amazon has copy's but be warned it is a spend y book.Ranjit Rai other books are great too.

[rickym]

This is good for here and there but here is the problem, the pot that you use can not stand very high heat for long. (We made one and it broke after after a little while but then again we did use it in a restaurant). You would be better off digging a hole and lining it with heat proof bricks. If your concerned about bugs getting, use a mixture of concrete & clay and line the hole with it, and let that harden, and then lite a fire in the hole to let the clay harden.