quest for outdoor cooking rocket

Hello All, I'm on the quest to make a rocket stove that I can use for cooking outside, mainly as a redundant way to cook food. I played with a couple of prototypes and have a few questions. My basic design has been a simple L tube. My first attempt was with 4in tubing. 2 feet of tubing going up and about a foot of tubing sticking about the bottom via a 90 adapter. We got to it work but it was pretty high maintenance keeping it going. The second design is 6in tubing 1 foot sticking up attached to a 90 and then attached to a 8 in increaser which i'm using as the burn chamber. It too worked but needs tweaking. Where do I want the fire to be burning, in the back close to where the tubing goes vertical or closer to the front of the burn chamber? I used a small piece of grill grate as my wood rest in the burn chamber of the 6inch version but i think it should be a solid piece so air draws only through the back or where ever the burn is supposed to be? I should've uploaded some pics but it's dark now and will do so tomorrow. Any input is much appreciated.
thanks Joe

I think any rocket stove for cooking is meant for a quick burn and quick heat, so the thing is to have plenty of fuel handy and just feed it all the time while you are cooking. I would guess that it doesn't matter where the fire is attacking the fuel in the pipe since the draft is pulling both flame and heat up to the top end anyway. I usually try to use either my solar cooker or the embers or top of my woodstove for slower cooking......

it worked much better when it's not raining and dry wood!! It is a hungry beast and uses a bit more wood than I want. I guess I need to insulate the 90 and the uptube a bit??
thanks, Joe

There are lots of designs on the web for rocket cookers. They use very little wood. Yours seems to be only partly insulated so may be this is part of the problem. See http://www.treehugger.com/corporate-responsibility/rocket-stoves-build-your-own-ultra-efficient-cook-stove-video.html for a starter. They can be made from anything from the size of a coffee tin to an oil drum such as http://www.rocketstove.org/index.php/institutional-stoves.

Thanks Roy those are awesome links!!