first homemade woodstove

[electrondady1]

 i'm building an outside woodstove/casting furnace from and old water tank.

i want to the capture the heat for my house by wraping the stove with airduct and pulling the hot air into the house with a fan.that should be simple and safe. i plan on placeing the firebox and air duct in a large pile of sand .

the air supply for the stove is a little different . it's starts near the front next to the door and runs through a steel pipe and ends at the back of the stove.

i did it like this be cause i would sometimes like to do some lost wax metal casting and blowing air under the fire can make it hot enough to melt copper and aluminum.

i intended the entire stove to be at a slight angle so the fuel would have a tendancy to fall down to the back and burn up completly.

i was thinking the combustion would take place towards the back of the stove and the hot gases would follow the top and exit through a vertical chimmney near the front

but this is kind of the opposite of how a normal stove works.

maybe the door would get too hot and the glass would break.

[electrondady1]

herese some shots







i was thinking with the door closed there would be a build up of smoke /heat unless the chimney were higher than the door

 any thoughts guys?

[keith o]

so far that looks quite close to a woodstove i built

a few decades back using a water heater tank

beware of few things with that water heater though

if it has a enamel? type coating on it?

it likes to pop off in little pieces when heating and cooling

and don't get it real hot then try to shut it down because

it will collapse on itself from the vacuum

been there done that

it would behoove you to weld some angle iron ribs length wise

for support

fwiw

[electrondady1]

thats a good tip keith!

 i could tie the rear legs into them.

and thanks for the warning about pulling a vacume.

after looking at the photos myself,

i'm seriously considering putting in two chimmneys and two dampers

one on each end .

so if it's a blast furnace or if it's a wood stove you could reconfigure to suit.

[stephent]

Actually the outside of that tank is galvanized--the first couple of times (or more) you fire it--fire it HOT--- outside of the house or enclosure. DON"T breathe the fumes from that stuff off of the outside when it's hot.

Way out in the yard somewhere, not just a few feet.

The glass lining inside should just slowly flake off during a few fires.

But that galvanize outside stuff's fumes are dangerous to living things when it gets hot.

Just a friendly warning from one who "used" to weld on some of that type of pipe way back. I don't do that anymore. Too many headaches (real headaches--mind numbing ones after breathing galvanized fumes) that close even outside in fresh air. And that's the nice side effect of that crap.

[WXYZCIENCE]

Electrondady, I have to second what Stephent has spoken about. The fumes from welding galvanized tanks are heaver than air and will sit in the bottom of you lungs. Drink some whole milk if you are going to weld any galvanized metal. The gas is very toxic.




Joseph.

[nanotech]

As to the dual purpose chimney setup, I would go for a heat baffle.  Line the top of the stove front to back with a flat plate.  Make two holes in it, one in the front, one in back.  Have a handle that you control from the outside that allows you to move a couple baffle plates to cover one or the other of the holes.  Slide it back to uncover the front and cover the back, slide it forward to do the opposite.

Let me see if I can draw something up.  I'm a lot better with pictures than I am describing things....

In the top portion of the picture the red box is the baffle plate I suggested welding in.  The two black boxes are the holes.

Then in the bottom of the picture is the slide rod and the two baffle plates.  The red dots are bolts that go through the two upside down U shaped pivot points.  They will also go through the slide rod.  Measure them out so that only one plate covers a hole at a time, and there you go!!

Just a suggestion to minimize on the chimneys......

[electrondady1]

i was aware of the welding hazard and  ground off the zinc for about a 1/4"

at the end of the tank before i welded it in.

there was some zink still present.i found  a bit of that white powder residue around the welds. there is still a lot of welding to do around the rim of the tank to seal it up.had a fan blowing on me as i worked and escaped with out a headache.

 but i'm geting concened with the posibility that the galvanize will continue to emit poison long term.

maybe i picked the wrong tank!

thanks for the diagram nanotech

a sliding baffle would be slick but i think it's beond my tools and resourses right now.

if i only had a cutting torch!

maybe i could tie the two dampers together with a rod.

[Darren73]

if you coat the area to be welded with anti spatter spray after grinding off the remaining zinc turns black during welding and doesn't fume off, I found this out quite by accident while doing some work and not wanting spatter stuck to the plate after welding

take care

Darren

[kell]

electrondady

This is going to sound too obvious but if you decide against the water heater, you can use a 55 gallon steel drum or drums.  I made a woodstove out of a 55 gallon drum many years back.  I had the drum on its side and a door on the end like yours.  It had a baffle.

One setup a lot of people have built is two horizontal steel drums, one above the other, connected by a piece of stovepipe.  You can build a chamber into the upper drum to use as an oven.

If you get a closed drum, there will be two bungs on the top.  Cut your door in the bottom of the drum.  Then when you lay the drum horizontal, the bungs will be at the back and you can use one of them as an air inlet.  The bungs have pipe threads, so you can screw a piece of pipe in, that way sparks won't fall out of the bung hole.

Reminds me of a ditty:

The bear went over the mountain

The bear went over the mountain

The bear went over the mountain

To see what he could see

Stuck his head in a char hole

Took a bite of the charcoal

Sparks flew out of his bung-hole

And blew his tail away

And blew his tail away

And blew his tail away

Sparks flew out of his bung-hole

And blew his tail away

[electrondady1]

i do have another tank slightly larger, 18"dia. this one is 16"dia.  

 i had intended to use it as a water jacket for this one in a a hot water system.

i have backed away from that plan and will continue with the set up i have and rig it up for  heating air.

a water system is just too complex to start at this time of year.

if i can make some progress tomorrow i'll post some photos.

[RP]

That's near exactly the way my "store bought" wood stove is designed and it works good.