Outdoor cooking project.

Hi All,
Just joined, so this is my first post.
I have long been a fan of outdoor cooking, not just BBQ's but real outdoor cooking.
My project for this year is going to be something along the lines of a Lo Trau.

http://www.google.co.uk/imgres?imgurl=http://upload.wikimedia.org/wikipedia/commons/6/60/Lo_trau.JPG&imgrefurl=http://en.wikipedia.org/wiki/File:Lo_trau.JPG&h=768&w=1024&sz=93&tbnid=SBqqWaiP4WOqrM:&tbnh=92&tbnw=123&prev=/search%3Fq%3Dlo%2Btrau%26tbm%3Disch%26tbo%3Du&zoom=1&q=lo+trau&docid=v5JCTtkx7jHL3M&hl=en&sa=X&ei=OExvT9b8Kce-8gPL1-zADQ&ved=0CEcQ9QEwBQ&dur=1

Basically I want to construct something that burns wood, has an oven and two hot plates. That's where I start needing help. I have got hold of a stainless steel chimney and cowl and would like to use reclaimed/recycled naterials where possible.
I am very interested in the idea of Rocket Mass heaters and the paving slab Kachelofen. If I can I would like to create something using the two ideas and the lo trau.
Any help, ideas, suggestions, etc would be very gratefully received.
Cheers
Nick

An open question like that can take up a lot of peoples time. I have spent hours, nay, months trawling round the internet, and though I can't tell you many links off the top of my head, as well as searching this forum (really heating oriented) www.rocketstoves.org, donkey32.proboards.com are a couple to start with and get some understanding of what's needed. There is loads to learn, and I admit I don't know much. There is not really a short cut to this homework IMO, you just have to settle down and do it.

Best of luck.

Hi,
Thanks for that. I love all the research, the internet is a time theif. I go on for ten minutes and two hours later!!
I was just hoping for some input from people with experience. I know basically what I want to do, but everyone has different ideas about how to do it and what to use, that's what I love about these forums, pooled resources.
Cheers
Nick

ive seen something similar made of earth and used in mexico. it worked very well.

Lorana stove will address most of the want. it could work for the oven as well if configured right.

Here's something that looks a lot like what you described:

Rocket Kitchen

I'm going to build one of these this summer in preparation for a RMH build later in the fall hopefully. I'm planning to change the design a bit on the kitchen in the link so that it uses a j-tube burner and a taller heat riser in the hopes of getting hotter, cleaner combustion (trying to keep the soot off of the pans as much as possible).

Wow, that looks fantastic. I obviously have a lot of reading to do. I was hoping to fire all three cooking points, two hot plates and one oven, from the same fire source!
What is a J-tube burner?

You could try looking at institutional stoves, but the prospect of using one fire for more than one hot plate and an oven will probably give some interesting control problems. If it was easy there would be quite a few about by now. It also presents a problem when you want to cook just one pot. Is the combustion chamber going to work at a low output as well as a high one?

If you look at the side view of the burner, a J-tube looks like a squared off letter 'J' and the L-tube looks like the letter 'L'. The wood in a J-tube style burner gets put into the top of the short leg on the J (fire burns down and sideways), and the wood in the L-tube goes in the bottom leg of the L (fire burns sideways and up). My limited understanding of the pros/cons of the two is that the J-tube has more turbulence and its ergonomic factors mean you can have a longer heat riser (thus better draft). The L-tube is probably easier to build though.

I have seen a design on the ol' intertubes somewhere that had three burners connected by a channel or duct that was fed by a single rocket burner. I don't know how well it worked. I suppose you could take advantage of the different heat levels and have a hot, medium, and simmer burner going at the same time that way.

Do you think taht particular goal is unreasonable then?
The kitchen in the post above look brilliant, I suppose it's no big deal to light three small fires as and when required. It was the Lo Trau that made me think of one heat source, obvoiusly the further away from the heat, the cooler the hot plate.

Beats me whether it's reasonable or not.. best thing might be to mock it up on the cheap and see what kind of results you get. I'd expect to see the burners further from the flame be less intense, but I don't know how to quantify it other than just try and see. You could probably do something with various sized vent covers to try to get more even heat at the expense of having lower heat all around (i.e. the burner closest to the fire has a tiny hole for the hot gases to get out of, and they get bigger as you go further from the fire).

If you haven't seen it already, Donkey's heater/stove has some (if not all) you are looking. Might stir up some ideas at the least...

http://donkey32.proboards.com/index.cgi?board=discuss&action=display&thread=11

the only problem i see is where to put the oven; control is as easy as a few plates in the ducting that you can open or close to direct the flow of heat. I simply haven't done one for that sort of configuration and since i cook i know that the oven is the hard part to get right. however: I can see where an earthen oven soaked in heat till it gets to about 400 degrees will stabilize around 350 and hold for at least an hour. I can see doing it with a rocket but will have to work out where to put things. normally the top of the barrel would be the place for a fry pan but then if the flame path was configured a bit different i could see a few more grilling areas. I order to do this you would be looking at a vertical chimney that was rather high to get the draft needed.


hmm i will think on it a bit more.

Hi All,
I am wondering if the oven is a little adventurous, I love the idea of an oven, but wonder if I would use it much. I think what I should aim at for this project is two hotplates fed by one fire.I think I could then add a separate oven at a later date fed by it's own fire I have looked at brick as an option, as I am in the UK and cob, clay, etc is fairly scarce.
Everytime I start looking I find something different, it's great.
As before all help, suggestions and ideas gratefully received.
Cheers
Nick

Nick, did you ever move forward with this project?

I most certainly did. After a couple of test firings and tweaks, I cooked on it for the first time last night. Brilliant. Only problem appears to be the "plancha" is not thick enough so needs beefing up a bit to stop warping.
It will taek a few goes before the plate is seasoned, but it's all looking good.
I will post some pictures when I get home tonight.
Thanks for your interest.
Cheers
Nick

Awesome, thank you. I look forward to seeing your pictures.

Pictures as promised.

Nick,

I am curious to know what adjustments you ended up making internally.

I wish I could find aerated concrete blocks in this market. They can be found in the Phoenix area, but that is 700 miles away. I will continue looking for a local distributor.

Could you let us know how they stand up to heat?

It is not unusual to have to reinforce the metal plate against warping. Check the Lorena, Justa and Ecostove sites to see some examples.

You are absolutely right, Andrew, On the first serious firing the plate bent up and then went back down as it cooled. I am taking it to get some extra bits welded on to strengthen it.
I made the area under the left hand side of the plate wider and shallower and made the burn chamber and heat riser slightly smaller.
So far all is standing up to the heat. I have bought some fire cement to firm things up if they start to wobble.
I am really chuffed with it. It burns so cleanly, virtually no smoke at all after a few minutes.
All I need to know now is how to regulate the hot plate temperature so that I don't cremate everything.
In the UK the blocks are made by Celcon, Thermalite and Durox. try the websites.
Cheers
Nick

I like the idea of mixing those different stove designs, but I'd keep it simple to begin with. Get the basic stove working properly before adding the oven and extra cooking plates. Reclaimed bricks are a great choice for the main structure, but I'd use heat-resistant materials anywhere the fire is at its hottest. I'd also make sure there's an easy way to remove ash and clean the flue—it'll save you a lot of hassle later on.