New guy with basic questions

I was thinking of preserving the solid bottom of the 55 gallon drum and flip it upside down, with the hole cut just big enough for the lid of the core to easily fit through, former top would just be removed entirely since the bung holes aren’t helpful. Would give a damper/baffle for the heat to dwell longer. I could also just add an afterburner but if I’m making it to keep refilling over and over I wouldn’t want to handle a red hot barrel, haha.


Build it an for sure explore new ways to do it! Post pics!!

For the barrels put eye bolts in them and use a hook to pull them out and of coarse wear gloves. But they are not that hot, the charcoal cools faster than you think. Your replacement barrel will be cold. I now have a guillotine cut off plate I install to block off the fuel from leaving the grate while you change the catch drums out.

If you do a removable catch bin you must enclose it do not catch the woods on fire!!


I’ve seen your catch barrels and I’m not too worried about how hot those would be, but I meant using another barrel as an afterburner would be pretty dang hot to remove each time I wanted to refill the hopper. Though with a hot water heater tank I would get a good 40 gallons of space per batch so I could make it a Once a Weekend type ordeal with one or two batches. I need to get a reserve of charcoal in case I need to power my little generator.

I live in the boonies so I don’t get smoke complaints luckily. I think they’d rather smell hardwood burning than garbage like some people still do around here.


Ah ok I got ya now. Yeah I wasn’t thinking of removing, just a small set of steps to get up there to load her up. Yeah here Mi we dont have issues like other states do. Plus Im out in the middle of nowhere too.


I’m already thinking how I can use water heater tanks to emulate Matt’s furnace.
Since it uses three cylinders, I think at least two of them can be water heaters.
I’ve found a plumbing supply house that will give me scrapped waterheaters for cheap or free.
Barrels are about 15 bucks, with lid.
I don’t like dealing with the paint, so I’d rather get a third water heater tank for the outside, but the bigger ones are harder to come by.

Matt, I’m hoping make a smaller version, to make sure I have the gist, and to use for cooking.
To that end, is there any part of this furnace that could be made in aluminum sheet?
Also could this design be built as nesting boxes instead of cylinders?

I go by a lot of handles, but Will is fine.
I’m old school American I’m my measurements but I can understand metric.


I dont know about aluminum. Aluminum and copper will dissipate heat faster than it can absorb it. The primary function of this kiln is to do just the opposite and retain as much heat as you possibly can.

There is no right or wrong way to do this. Build it and experiment. The function you want to get working is getting the second stage to combustion upon leaving the side vent holes while sustaining primary air intake flows in through the grate. Once you have this you have basic concept working. What you do with it after that is up to your own imagination.


I was only thinking about heat resistance, not retention/ dissipation.
Definatly gonna study your thread more, thanks again!


I agree, I think it could be done. But considering practicality. It takes time to get things working and started and operating and adjusted. I can not think of an application for starting an engine for 10 or 20 or maybe 30 minutes only. I guess in some really specific situation trying to charge some batteries etc… I think I would get frustrated by the amount of time and energy spent to make an engine run for just a short time before the quality of the gas changed and I’d have to be making constant adjustments.
aLSO, will it still be a TLUD once you apply vacuum to it to remove the gas and move it to the engine?

With that said, if anyone knows what he is talking about…it’s Matt above.


Well no, when the burn has made its way all the way to the bottom a tlud becomes a charcoal brazier, If you want to argue semantics. I didn’t think we were into that around here.
My water heater tlud was not imagined to be a char gasifier. And though it would probably work for a short time there are much better, simple char gasifiers to be found on this site. I made one based on @k_vanlooken’s Some School In Thailand thread. It will supply gas to my 3KW genset for about a half hour. I take the charcoal I made in the tlud and put it in there. There needs to be ~24 inches of charcoal above the nozzle to make good gas. I plan to make a new one with a larger diameter and a 5 gallon hopper above the 9 inch diameter 24 inch long pipe. I plan to insulate the inside of the pipe with an inch thick ceramic wool blanket. I hope this rig will give me two and a half hours runtime.


I made a new thread to solicit advice on the tlud boiler.