You need to close the small drum, how you do it is the $64,000 question. Raise the small drum off the bottom of the big drum & put the lid on that one too(you will need a stack out the top of the lid of the big drum to let the heat & burnt gasses out). The theory is that you want to surround the small drum on all sides with heat & not allow oxygen in to let the wood burn(hence the holes in the bottom) this way you will burn all the gasses & moisture out of the target wood without it actually burning.
But if you want to go down the cheap and easy route. Put holes in your inner tin lid and fill with wood. Put the lid on securely and put upside down in your larger barrel with stops so the smaller barrel is above the fire (upside down with the holes in the lid facing down). You might need to put a hole in the top lid of the larger barrel for smoke to exit. The priciple is the fire heats up the smaller barrel with the wood in it. The wood gets hot but without enough air to ignite. So it kind of steams the sap etc out and that needs to escape (hence the holes in the bottom). As this sap is flammable it adds to the heat. After several hours and no more flammable sap steam coming out of the smaller barrel you can wait for it to cool and then disassemble and open the smaller barrel. Don't do it too soon as if it is still hot and you add air it is only going to ignite.
Hope this is of some help.
Learning generally boils down to "Repetition or the avoidance of pain", some people learn by doing, some by watching and some just have to pee on the electric fence.
Whether you think that you can, or that you can't, you are usually right. Henry Ford
The day after I asked for help winter came and I've been on the snowplow since. It rained on newyears eve and washed most of the snow away, so I set up my drums to cook some wood.
The inner drum was too tall so I couldn't build the fire in the bottom of the large drum. I set up some blocks to hold the fire. I made a rack to hold the drums out of som 3/8 X 1" scrape steel.
I put some handles on the smaller drum and cut a lid from an old highway sign, I didn't steal it off the post, Honest.
Three spring fasteners hold the lid on. I hope it doesn't warp when it gets hot, if so I will use a piece of 1/4" plate.
I cut some dried Alder into smaller 3"-4" chunks and filled the drum then I cut the bottom off the large drum and placed it over the smaller one. Once it gets light outside I will start the fire and see how it goes. Once the fire gets things hot I will put some more blocks around one opening to keep more heat in. It's 10 degrees below freezing with a wind warning so things may not go as planned but todays the only chance I will have to do this for quite a while and I'm too impatient to wait.
Will update the results.
I started the fire and blocked off one opening in the blocks once things warmed up. The ground temp was 17 deg F. after an hour and a half the outside of the large drum was only 100 deg. I filled the fire pit with fir and got a roaring fire going, the wind was gusting 35 to 60 knots so there was smoke everywhere. At the four hour mark there was flame shooting out of the fire pit and the drum was 600 to 700 degrees on the leeward side of the drum, windward side was 200-250 bottom to top. After the fire burned down some I was able to get close enough to take a photograph of the gas burn-off. I kept the fire going until the eight hour mark then went in to thaw.
Went out at daylight to check the results, we have charcoal. The volume in the drum reduced by about a third and the size of the charcoal pieces were also about two thirds the size of the wood chunks. The charcoal is also quite brittle, I kept the fire going for quite a while after the gas-off stopped, maybe I should have just let it burn out after gass-off?
I started another batch today, I wanted to use larger pieces but the alder is already cut. I will try a smaller fire and let it burn out after she gasses-off.
I used one wheelbarrow load of alder for the charcoal and two wheelbarrow loads of fir for the fuel. Cost me nothing for the wood so my only output is some mig wire and some time. The power was out most of yesterday and it was too cold to do much else so hanging around the backyard making smoke and having a couple of beer then cooking up a standing rib roast wasn't a bad use of the day.
Also something I'll be delving into at some future date.
Learning generally boils down to "Repetition or the avoidance of pain", some people learn by doing, some by watching and some just have to pee on the electric fence.
Whether you think that you can, or that you can't, you are usually right. Henry Ford
Yesterday I tried a smaller fire and between doing my year end sales taxes [yuck] added wood every hour or so. After 4 hours of cooking the can there wasn't much going on that I could observe. I split up some cedar and threw it in just to get some high flame going. HOLY BLAST FURNACE!!! The gasses shooting out of the bottom of the drum ignited and really heated things up. It sounded like a bunch of tiger torches going. Kind of reminded me of heating up a frozen D-9 cat stuck in frozen muskeg with a Herman Nelson, but that's another story. The gas was shooting out of the bottom of the smaller drum with such pressure I thought it was going to launch. My wife, expecting NORAD interceptors to show up, went inside. The flames were blowing out of the fire box three feet. Of course I got a couple of beers and enjoyed the show. I let the fire burn out after the gas-off. When I opened the drum today I expected all the alder to be burned away but I got another batch of charcoal. It wasn't quite as brittle as the first batch and a bit heavier. All in all a good result. I think.
As Big T asks I will tell you how it burns when the time comes, that will be when I find out if it was worth the effort.
Attachments
Heating up
Minus ten seconds and counting
Proof that I didn't steal the road sign off the post.
Crazy? Well they do call me 'Mad Man".
I'll compare the home made stuff with some store bought. If it burns close it will be worth the trouble, if not??? It was fun watching the drum in 'launch mode'
As far as the road sign, was that over the top? I'm sure most drivers will still know what the sign stands for. After all with the price of steel......
A week yesterday was wild card weekend and what better way to watch football than enjoy some hot chicken pieces?
I filled a chimney with my home made charcoal and started it up. It lit quite quickly, almost like a chimney of kindling.
I put the lit charcoal in a Weber kettle and burned off the grill. The charcoal was quite hot and seemed to be burning rather rapidly, I was starting to think it would burn itself out before I grilled the chicken. I seared the hot spiced chicken then moved it over for indirect cooking and closed the vents down to a sliver. An hour or so later we had some great hot chicken pieces for the game.
My observations on the first trial were the lump started faster than briquettes and burned faster than briquettes. I closed the vents completely after I cooked the chicken and there was some usable charcoal left the next day, but not as much as there would be if I used briquettes. I think there is more energy stored in the briquettes than my homemade lump and the briquettes burn longer. But a chimney of lump is a lot lighter than Kingsford, if I went pound per pound it may be a different story. I never use lump so I can't make a comparison untill I get a bag of store bought for test purposes. But the lump worked well and has a nice flavour to it, so far I'm happy with the results.
Now if I could dig out that five foot dia. culvert that goes under the road about 200 yards from that road sign, then get into the National Park and cut a couple of tuck loads of fir logs I could up the production. No, my wife wouldn't go for it.
I wonder if they have a grill or smoker at the local police station, it seems they lifted a few finger prints off that sign.
Been a while,
Never did buy any lump to compare.
Used the homemade stuff in the reverse flow, worked OK but burned twice as much as I would if it was Kingsford. Although I made one batch with wild cherry I didn't get a chance to make much more this winter and now we have a complete burning ban on the island. I will continue to use it until it's gone and stockpile some more next winter. Just cost me some time.
Would still like to use just wood but have not found any real hardwood yet.