Wood Furnace on the cheap

[biggkidd]

Hi Guys,

You all know we froze last time we went out to the property. The temps got down to 7*F. Thats way to cold for me. With all the heat we had in the camper it still got down to 51*F inside. Burr cold. So to keep this from happening again I have built a home made wood furnace. To start I bought this kit from Northern.

And two steel barrels from a guy across town. Here are all the parts laid out along with some ducting I got from Lowe's and Habitat Restore.

Here are the parts that came in the kit.

Not bad for under $50 for that kit. The barrels cost me $6 each. I think the ducts and stuff cost more than the stove did.

I started out by marking and cutting the first barrel.

I made the strait cuts with a skill saw and metal cutting blade.


I finished it out with the jig saw to make the curved cuts.

Then before putting the door on I put the legs on.


Then I cut and installed the damper. That was the hardest step in my opinion.


Next came the door.


Well that pretty much takes care of the stove. Now for the fun part. Time to turn a basic wood stove into a furnace. This gets quite a bit more interesting to make. First how to do it with no plans to work to, just an idea. After much discussion with a couple of my friends who were over I went back to the basic design I had originally thought of. Stacking about half of the second barrel on the first to make a enclosed heating box that would not get smoke in it.

First I set the stove on top of the second barrel and marked it on both ends and down the sides. Then I cut those lines. Then I cut the barrel about two thirds of the way down. Heres what I was left with at this point.


By pushing those two pieces together I had a heat box that fit in the space in front of the chimney.


Then I did a test fit to make sure that would work out like I wanted.


As you can see quite a bit of grinding was needed at this point. I wanted it to fit as tight as possible to the stove. Next I had to make the flanges for the duct work to slide into.

First I marked them out trying to keep one high for the exit and one low for the intake.

The plan is to draw air out of the camper into the heat exchanger and back into the camper.
Here you can see what I came up with for the intake and exhaust in the heat exchanger.


The pipe going inside the exchanger is the intake and the adjustable elbow is the exhaust.


You can see how I set the flanges up different for the two pipes. The intake which goes inside has been supported on both sides while the exhaust is only on the out side.

Then I noticed that I had put the damper in turned the wrong way for the pipe arrangement I had. So I had to take it back out and turn it around. What a pain.

You can see where it would interfere with the intake. Then I welded the heat exchanger on the stove. Sorry I forgot to take a pic.
Then I made a grate for it out of some 5/8 steel stock I had laying around.

Then I used some furnace putty to seal the heat exchanger up since I didn't want to weld it all the way around. Mostly because I kept burning through the barrel.

Well its done except for a final coat of putty and paint. I wanted to burn it first to get any of the other paint off.

Here is a shot of it in action.




Heres one with flames coming out the chimney.


Last but not least one of the back side the long pipe at an angle right now is the heated air with the intake on the other side.

You don't feel any heat coming out the intake and its around a hundred degrees on the heat pipe. I have had it so hot I couldn't put my hand over the heat pipe but turned down like I expect to run it, its around 100 maybe a little higher. ;D

Still lots to come on this when I get it out to the camper and install it. Then I get to see if it really works.

I have a 12 Volt fan to push the air into the stove from the camper. The camper has three floor registers I will add an intake somewhere. Maybe under the kitchen cabinets. That would keep it out of the way in such a small space with 4 people in it.

So do you guys think this will handle our heating needs???

Thanks for looking.
Have a great day.
KIDD

[biggkidd]

Hi Guys,

I finally have a update for you on the furnace. I would have posted last week but as you know I have been sick. First it works, and pretty well at that. It goes through lots of wood though.



The pipe you see on the left of the stove is the intake from the camper. I have a 12v fan pushing the cold air into the heat box. The heated air pipe you can't really see from this pic. The fan is not strong enough I may try using 2 or a different type.



I had a base of embers about 8 / 10 inches deep at bed time. So I loaded the stove down with as much wood as it would hold and went to bed. Only to wake up at 2:30 or so sweating it was 78* in the camper and 25* outside. I had to get up several more times through out the night and feed the stove but we stayed warm as toast. I am shocked at how much wood we went through in one night. I will need to learn this stove to get the temp to stay comfortable. I am planning to do some more work on the system but so far so good. It sure beat freezing like the weekend before.

I have the stove trying to feed three floor registers off one 6 inch line. I hope adding another fan or a different type of blower will help even things out. Right now the bathroom stays hot & the front room stays cool.

I think closing the sides of the stove in will help a lot as far as wood consumption goes.
I will probably change things around till I get it just right then I will post more about it. But the basic idea works.

If any of you have ideas to improve please pass them along.

KIDD

[3RRL]

Kidd,
I saw how you made that thing from scratch and found it extremely interesting.
I wish I had some some suggestions to make it better, but my wood burning stove knowledge is next to nothing except I know you need a stove and wood for sure. ;D
Rob-

[GuglioLS]

Hey KIDD,

Don't take wrong, I mean it in a good way -

That home made stove hooked up to your trailer looks exactly like a scene right out of the Beverly Hillbillies I just love it! So it works good? Man you sure know how to make stuff work for you on the cheap. Great job putting all that together and in record time to keep the family warm. How many acres did you say you have? If I remember correctly you have so many "Green Acres", you now qualify as a Land Barron. Congratulations on your new land purchase. I look forward to reading all about your activities there.

Larry

Greeeeeeen acres is the place for me, Farrrrrrrrm living is the life for me, laaaaaaaand spreading out so far and wide, keep Manhattan just give me that country side!!!!!!

[biggkidd]

Rob, Larry,

I enjoy doing things on the cheap. Looking like the hillbilly's isn't so bad. Its also very rewarding to see just how much can be done with so little. Larry we have 36 ac I am not sure that would qualify as a land Barron but its sure a great place to be. I will be glad to get a house built but it will take some time and as few dollars as I can manage. I like the idea of living in a house I have built my self. I realize thats not for everyone but it works for me.

I also try to keep in mind the less I spend on camp the more I can do toward the house. But I do need to be dry and warm to get anything at all done. Camp is just temporary too, unless we fix it up and turn it into guest quarters. for you and Rob to visit.

Have a good one.

KIDD

[biggkidd]

Update

I have added a little to our furnace. I dry stacked cinder blocks around it. We now have heat all night long without refilling the stove wood.





I still have to seal off the top edges and close in the front. But this thing works like a champ. Even better you can burn anything in it. So far we have burned pine cedar oak and iron wood.


I would strongly recommend this design for a hunting cabin or other structure that needs an out side low maintenance heating system. Total cost of the furnace not including the duct work but including the cinder blocks is still under $200.

I hope some one else can use this info.

KIDD

PS Look Larry it doesn't look as much like beverly hill billys now.

[red]

Larry nice job-
You did get the mineral rights to your land? Before you go hunting and find that bubbling crude- which pasted the $100 mark yesterday. Your story of getting up at nite to feed the fireplace remind me of Larry G's story of free wood. Most things that are free require a lot of work guess that's why they call it sweat equity. -Ed

[biggkidd]

8-)Hey Red,

Long time. Yes we did get the mineral rights... ;D Now if I gold just find some of that liquid gold or the real thing in that area. Its right on the edge of the VA gold belt.

Most things that are free require a lot of work guess that's why they call it sweat equity. -Ed

All too true. But its a lot of fun too.

Thanks for your comments.

KIDD

[Ronmar]

That's pretty cool! The hardware in that kit will probably last forever. When the barrel burns out, look for some old steel wheel rims of the same diameter. You will need 4 of them. Cut out the center flange on each wheel and stack them rim to rim and weld around the rims. You will need 3/16-1/4" plate to cap the ends. Makes a very similar design stove, but with more surface area and an antique cast iron radiator look. It will also probably last forever:) I saw a 2 barrel version of one of these in a shop picture, and it looked pretty cool. It appeared to have been assembled with the same parts as that barrel stove kit(only the one for a 2 barrel stove).

I am actually looking at doing a similar outside furnace project to heat my garage. We switched from a small "country" brand woodstove to a pellet stove a few years ago. I kept the woodstove for the garage, but I don't want to loose the floorspace that a woodstove installation would require. I am going to set it up outside like you did. I will place it in a metal box with insulation on the outside, and duct air from under one of my workbenches to the bottom of the box, and take air out of the top of the box and back to the garage wall. This setup will circulate naturally, but I will also add a fan to push the air along thru the box. I am going to weld 1" strap fins to the sides and top of the woodstove to act as heatsinks to increase the surface area and heat transfer to the air flowing thru the outer box. I was looking for an old flamable storage locker(double walled) that would neatly contain the insualtion between double walls, but havn't come across one yet.

One of the biggest advantages I see from this, besides the retained useable floorspace, is it keeps the wood mess outside.

Ron

[red]

ronmar said:

That's pretty cool! The hardware in that kit will probably last forever. When the barrel burns out, look for some old steel wheel rims of the same diameter. You will need 4 of them. Cut out the center flange on each wheel and stack them rim to rim and weld around the rims.

One of the biggest advantages I see from this, besides the retained useable floorspace, is it keeps the wood mess outside.

Ron

Great idea That's the biggest problem I have with the wood stove is the mess. Around here the local authorities just put a band on those outside wood burners (takes a full 5' log) Most of the outside wood stoves would use hydronic pump and tubing to move the heat- ya didn't want the fire box too close to the house

Kidd -
it was just on the news about the gold rush in Mexico less than a days ride from the US border. You could probably make more money letting those "greenies" pan for gold in your stream. Of course you could always throw some Fool's gold in the stream to peak some interest. ;D -Ed

[biggkidd]

Yea the furnace is finally done.

I finished closing in the furnace this weekend. Boy that thing works.




It sure is nice now that I can load the stove and come back 12 hours later and its still hot. ;D

If anyone thinks of doing one of these let me know first. I would make some changes in hind site. For one I would mortar the blocks do away with the heat box made on to the stove. I would just use the cinder blocks as the heat box now. This is a super efficient setup now.

KIDD

[FlyHiFlyLo]

Hey Kidd awesome setup! It really looks like it would kick ass!

That is a great stove kit and you did an awesome job putting it together.

One thing for your safety. Since you added the bricks to the outside; overtime it may force some carbon monoxide into the secondary chamber. Just for you and the kid's safety you might want to consider a carbon monoxide detector just for cold comfort... No pun intended.

Awesome idea for semi-permanent camps!

[FlyHiFlyLo]

Maybe a cheap Thermostat hooked to the fan or an old power car lock solenoid hooked to a flapper in the duct could regulate the heat?

[GuglioLS]

KIDD,

Now that's hot, It looks like you very own personal nuclear reactor. Very cool idea. Maybe the barrels will last longer now that they will be out of the rain?

Larry

[biggkidd]

Hey Scott,

Thanks man. A co detector is a must that I still need to get. I think I may add in a way to blow the heat outside when the camper gets warm. I am afraid the furnace will get to hot if the heats not going somewhere.

Larry,

What no more comparisons to the Hillbilly's? JK I know it still looks like the hillbilly's. I do hope that it lasts a few years. Closed in like it is it should. Plus I learned a lot. I may build something of the same sort but longer lasting and bigger when we do the house. Speaking of the house I think we found where we want it to go this weekend.

Thanks for looking.
KIDD