Wood Stove Project

[ThrottleJockey]

I have started a new project to try to get a bit more efficiency from our simple barrel stove. I have welded a barrel lid from a 55 gallon barrel to the top of a 30 gallon barrel and cut out an opening. I will put the 30 gallon drum inside the 55 gallon drum and pipe the stack through to the chimney. This will leave me with the 30 gallon drum as a firebox and the 55 gallon barrel will become a heat exchanger with a blower on the back and a vent on the front. I expect to get more heat and burn less wood at the same time with this setup when I finish it. Here are a few pics of what I've done so far. I'm noticing that the 30 gallon drum has thinner walls and is tough to weld with my el cheapo 2 temp welder, I may have to find a water heater tank to use instead for fear that this barrel will burn through too quickly when it is put into service.

Here is a view of my crappy weld...needs some work still!

Here is a view with my current stove.

I'll post more as the project progresses!

 

[Joel_BC]

Real interesting project. Thanks for posting the pics. I had a bit of a hard time visualizing the design from your previous (verbal) description.

The blower should allow you to direct the heat out into the room, closer to floor level or waist height. Without that, a lot of the heat from a woodburner tends to rise straight up from the outside surface of the unit.

 

[ThrottleJockey]

Agreed. The blower I have was salvaged from an old Ashley stove that was burned out pretty bad. There is a thermostatic control on it but I'll likely remove that in lieu of a toggle switch or variable speed control...In fact, the door and flange I'll be using also came from that old Ashley. I really like re-purposing things, I can't stand to throw things away if there's a chance I'll have to buy something similar in the foreseeable future. I've seen some people will stack small-medium sized river rocks or boulders around and over the barrel and even mortar them together creating a sort of heat exchanger/heat sink. This creates more of a radiant source but also stores the heat long after the fire is extinguished.

 

[justin_case]

real interesting,

I would worry about the barrel burning through as the years go by. I think adding circular split baffels to make a screw type baffel around the outside surface of the inner barrel would aid in heat transfer. If the air travels around the outer surface of the inner barrel a couple times before exiting it should pick up lots of heat, or maybe not worth the effort?
You have given me some ideas to roll aroud in my head.

 

[Beekissed]

We are thinking of putting some mass around our barrel stove next year so we can get a longer lasting and more radiant heat from the wood we are burning, without going all the way into rocket mass heater territory. We are going to change out placement of stove pipe and build a three sided casing of stone around the sides and back with a flat metal sheet on top that can be lifted off if need be so we can remove the stove for maintenance at any time.

We want a flat surface for cooking and also some mass to slow down the heat release, store it and release it later when the stove is banked down for the night. It will look nice and rustic in our log cabin and will help us get more radiant heat from the simple stove, but it won't cost much to do.

 

[ThrottleJockey]

We are thinking of putting some mass around our barrel stove next year so we can get a longer lasting and more radiant heat from the wood we are burning, without going all the way into rocket mass heater territory. We are going to change out placement of stove pipe and build a three sided casing of stone around the sides and back with a flat metal sheet on top that can be lifted off if need be so we can remove the stove for maintenance at any time.

We want a flat surface for cooking and also some mass to slow down the heat release, store it and release it later when the stove is banked down for the night. It will look nice and rustic in our log cabin and will help us get more radiant heat from the simple stove, but it won't cost much to do.

I have a 1/4 inch thick steel plate that I plan to fashion into a cooking surface that will just sit atop the barrel and perhaps create some sort of metal or even wood open bottom box that will set on top of the cooking surface to use for baking. I won't use it everyday but it will be nice to have the option should there be long term power outages for whatever reason...


ETA now that I think about it a hinged hatch into the heat exchanger would make a nice convection oven...

 

[baymule]

Neat project ThrottleJockey! You might want to burn off the paint on that Shell keg barrel before you assemble it all together! And your weld looks OK to me. If it holds, who cares if it looks like an attack of dirt daubers?? (we pronounce it dirt dobbers here ) My Daddy had a barrel set up in his shop/greenhouse that was 2 barrels stacked on top of each other. The fire was built in the bottom barrel and the heat entered the top barrel at one end and went out the smoke stack on the other end. It really warmed things up! Good luck on your project and be sure to update with more pics!!

 

[ThrottleJockey]

Neat project ThrottleJockey! You might want to burn off the paint on that Shell keg barrel before you assemble it all together! And your weld looks OK to me. If it holds, who cares if it looks like an attack of dirt daubers?? (we pronounce it dirt dobbers here ) My Daddy had a barrel set up in his shop/greenhouse that was 2 barrels stacked on top of each other. The fire was built in the bottom barrel and the heat entered the top barrel at one end and went out the smoke stack on the other end. It really warmed things up! Good luck on your project and be sure to update with more pics!!

Those 2 barrel stacked stoves work pretty well at scavenging a lot of the heat that would normally go out the pipe. Oh yeah. It'll get burned off outside before it gets finished. My biggest concern about my welds is the lack of skill that went into them. I burned through in a lot of places and need to go back and patch it all up. Another idea I have been kicking around for a while is to run copper tubing around the inside barrel to pipe water through...don't know how well that one is going to work though. About burning through the barrel over time, sure, that's expected but barrels are cheap (free). I actually didn't expect this one to last as long as it has. A key part of getting long term use is to keep it dry when not in use. In the summer I take it apart and empty all the ash and the sand base out of it so it doesn't gather and hold moisture.

 

[k15n1]

A double-insulated setup should be fine as long as the coals are on firebrick or refractory cement. If there's adequate circulation of air outside of the 30-gal combustion chamber, the metal shouldn't get hot enough to warp. This may take significant air flow. Do you have a multi-speed fan?

Also, consider putting in a baffle to increase the amount of the wood gases that are re-circulated and burned.

 

[windyoak]

I just came across this thread. Its a bit late, but what the heck! I am interested in making my own wood burning heater/stove. The one in this picture is one I made from an old propane tank. I lined the bottom of it with an adobe/cement mixture, and it has lasted me two years, so far, and it shows no sign of wear. The metal is thicker than an oil drum. When I get the chance, I would like to make another propane tank heater that is loaded from the side (instead of the end) with the flue exiting the other side. But my ultimate, fancy, project would be a wood burner made from cut slabs of stone bound together with a welded iron frame something like those that are advertised in Mother Earth.

Sorry about the picture ... how do you add a picture to your posts?