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Gray Simpson
Posts: 67
Location: McDonough, GA
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I want advice for making an outdoor fire, mostly for roasting marshmallows. The most important thing is to produce as little smoke as possible.

First I tried a Dakota fire pit, but that failed miserably (maybe because soil stays wetter in Georgia than in the Great Plains?).

So the other day I made something similar to this. I wasn't able to make really clean cuts, but it holds together fine. I don't have anything to insulate it except crumpled aluminum foil.

It worked much better than the Dakota fire pit, but I had to constantly take care of the fire. If I used anything other than dry, split hardwood (and plenty of it), the flame would die and it would start smoking. I want to get rid of some of the privet branches I cut a few months ago.

So, any tips?
 
Erica Wisner
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Location: Okanogan Highlands, Washington
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Gray Simpson wrote:I want advice for making an outdoor fire, mostly for roasting marshmallows. The most important thing is to produce as little smoke as possible.

First I tried a Dakota fire pit, but that failed miserably (maybe because soil stays wetter in Georgia than in the Great Plains?).

So the other day I made something similar to this. I wasn't able to make really clean cuts, but it holds together fine. I don't have anything to insulate it except crumpled aluminum foil.

It worked much better than the Dakota fire pit, but I had to constantly take care of the fire. If I used anything other than dry, split hardwood (and plenty of it), the flame would die and it would start smoking. I want to get rid of some of the privet branches I cut a few months ago.

So, any tips?



If you don't want smoke, don't burn green wood.

Burning green wood (aged less than 6 months) is going to be intrinsically smoky. Even with the best rocket stove, you will want to mix it with aged wood to get a truly clean burn, or preferably just go with aged wood.
Hedge branches are one of the things our EPA friends hate with a passion. People who should know better keep trying to burn green wood and creating terrible smoke. Ornamental nuisance woods like laurel, privet, and 'tree-of-heaven' are often particularly stinky when green. Age it for a year, and find older wood from someone else's old burn pile, slash pile, or shop scrap for your current efforts. Your marshmallows will taste better, too.

Insulation: crumpled aluminum works OK up to about 400 degrees F, but can melt above that. A truly smokeless fire is going to run 1500-1800F or hotter. You will want good insulation, and ideally some thermal mass inside it to help hold the heat and keep your fire going hotter as it shifts and settles. For insulation you can use wood ash or charcoal, collect it as you experiment. Or make your own with sawdust and clay, it will smoke as the sawdust burns out, but the right mix will produce a ceramic-type foam in the end.
For thermal mass consider a tiny batch of cob, or some slabs of (fire)brick for walls and floor.

My preference for roasting marshmallows is the even heat from coals, not a bare flame from a new fire. Chopping the wood into kindling and laying a cross-grid will give you coals faster than a big-stick fire. You could do this in a brasier or Hibachi-style barbecue pan (air feed from underneath), and make a sheet metal 'hat' for it with a tin-can chimney to help the wood burn cleanly until you get to the charcoal stage. Once you have glowing coals, it would be cool to be able to prop up the lid for marshmallow access, while still retaining some of the benefit of the chimney for smoke, and the hat can also reflect more heat back down for quicker, more even marshmallow golden-browning.
We've even roasted marshmallows over an electric stove, though the cleanup can be intense if you let them drip.

If you are of the flaming-marshmallow persuasion, then the coals don't matter as much. Consider a J-tube rocket stove where the wood feeds downward and you can keep your hands free for marshmallow-turning.
Or try this jug stove setup: http://www.ernieanderica.info/jug_fire.JPG. It worked for us in Oregon clay soils, though you will want to give your fire a little dry bed of ash or charcoal to get started easier. The form is based on an African tea-stove, dug into a hillside or termite-mound for on-the-spot tea sharing with chance-met friends.

The Dakota fire pit (http://www.survivaltopics.com/survival/the-dakota-fire-hole) is not a bad idea. Two things may improve it. A traditional variation was made using an existing fox- or badger-hole (abandoned, obviously!) and the angle these animals dig their entrance is great for feeding both air and wood. Check the angle and size of your air feed against the animals' hole or the drawing toward the bottom of the linked article; experiment a little.
When you dig the 'chimney' or firepit end, don't make it quite so big. Pile the sods/mud in a ring around the hole. This extends your chimney to improve draft, reduce smoke, and places your cooking support at a convenient height above the flames. Make the air hole slightly bigger, and you can feed in sticks endwise through the air hole without needing to reach down the 'chimney'.

Hope that helps,
yours,
Erica
 
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