I need to make about a cubic yard of charcoal. If it isn't created in small chunks, it will have to be beaten into small chunks, as it's for the garden.

My minimal understanding of the process is that you get a good fire going in a metal barrel or something that has some holes in the bottom, add wood or sticks or stuff like that, then mostly shut off the oxygen and let it char.

Some additional details would be great. I'm looking at trying a bag of stove pellets if no one has anything bad to say about the idea.

Sue

I find it a lot easier to use wood that is about 1/4 to 1/2 a cubic foot or so in size. For the process I use, if it is too small the fire consumes it too quickly, and if too large the center doesn't convert so well. I actually have an easier method for smaller quantities, but for the amount you need to make, I would start with about double raw wood. Dig a pit and get your fire going. Let about a third of it go to ember, your fire will be good and hot. Get a steel pipe about a yard long with a cap on one end and stick the open end near the base of the fire. Smother the fire with dirt, leaving the pipe sticking out. You want to build the fire so that it will have enough structure that the dirt won't just fall through it and fill in all the little spaces. Now here's the tricky part, you want to bake the wood for at least a few hours (hardwoods, by the way, make better charcoal for cooking purposes). If the combustion quenches completely, then the wood pile may cool too much, and it won't convert all the way. You can remove the cap to let in a little more oxygen once in a while. It is one of those things where you learn by experience what to look for, how the ground feels above the fire, etc. About half the time I end up with a decent set of charcoal, which I can break up with a hatchet or hammer easy enough. I like to use maple or alder, but I guess oak is the best for it.

My cheater method is to build a fire, use one of my dutch ovens with a tighter fitting lid, and put some wood in it and cook it charred. I can make a couple cubic feet at a time this way, and it is a lot more reliable.

Don't use aluminum. The combustion level and reactive vapors will dissolve it into your wood and it'll make a mess of it all.

Sounds like Benjamin has the best idea. I was going to say you had it about right Sue. The trick is to get the fire hot enough to cook and char the wood that's put on top without burning it completely into embers. However you do it, you're still going to have lots of ash and embers from the base fire. Use them, they'll be good for your garden soil too.

Okay, that is all making sense. Love the dutch oven idea!

Thank you.

Sue

So basically, you make char cloth, but with wood? Or is that a gross over simplification?

Umm, should be about the same approach I reckon. I suppose you could make a big batch o' char cloth by stuffing a piece of cotton clothing in a dutch oven and doing it like I would my charcoal. When I am swabbing down my dutch ovens during a seasoning session, I use cotton patches from towels and tee shirts, and they will smoke up enough that they will easily catch fire later on. They get loaded up with burnt oil/grease and turn almost black themselves. I never thought to save any of them for firemaking, but maybe I ought to give them a real test. Might've just stumbled onto something here. I can give this a spin this weekend on my bbq and let y'all know how it goes.

I have never needed to make charcoal, but you got me thinking (something I don't seem to do much of these days). I wonder, assuming that one has access to empty metal drums, if you could take a 30 gal drum, cut one end out, punch holes all around the sides (the pointed end of a pick works well for that), then fill it with some paper and your wood, and lite it off (like the burn barrels we used to be able to use in some parts of the country). Once is it burning well, take a 55 gal drum that has one end removed and turn it upside down over the smaller drum, in effect sealing the fire inside. When the oxygen inside of the drums has been consumed the combustion should stop. Kind of like a char cloth tin. I suspect that timing the snuffing part would be critical...

I think size may matter in the quality control aspects of making charcoal. The bigger the fire pits, the less consistency I seem to get from my charcoal. If you had a way of introducing a controlled amount of oxygen into the chamber, then you would be able to keep the decay process moving so that more of the wood converts without having too much charcoal turn to ash. It is all a balancing act, which is what makes the dutch oven process seem to do better. Smaller batches somewhat isolated from the direct combustion area seem to be most effective.

Given that, yours should be a viable process with substantial recovery still possible after some practice I reckon.

I guess that if one cut the bottom out of the 55 gal drum, that would leave the bungs intact on the top. One could be removed and replaced as needed, in an attempt to regulate the oxygen. Seems like too much work to me though.

Susan, could you just go to the store and by a bag of briquettes (what are those things made out of anyway?), then smash them up???

I think the brickettes are made from coal (not entirely sure). I'm also unsure whether they contain potassium which I think is what Sue is looking for for her soil.

I might be wrong on the science of this postassium/charcoal stuff (I was wrong once during a debate in 1975 ), but, in any case, I put our woodstove ash and charcoal from my daughter's marshmellow firepits into the garden and work them in first chance I get - even in winter. I read that ash losses it's ability to help the soil if it's rained on or thoroughly wetted before being worked into the soil. I don;t understand it, I just go by that.