Building a Large Wood Stove - Two Flues and other questions.

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Ray3

New Member
Dec 26, 2021
3
Maryland
Hi, new here, in north eastern Maryland. My shop is 60x96x16, and I have my eye on an old fuel tank to build a stove out of. Just drove by the tank today so I don't know the exact size. Looks like its about 3' round and 5' long. My first question would be, what is the thinnest metal I can get away with using for a stove? I can't imagine the tank is much thicker then 3/16''.

My next big question is can I make the stove with two chimneys? The reason I want to do this is because (I'm cheap) I already have enough 6'' pipe for 1 chimney, and I am assuming with the size stove I am planning on making I will need at least a 10'' flue. I have plenty of attic space to move the flues apart from each other or just raise one higher then the other and I am already going to run my flue as close to the ridge as possible. I'm wondering, will two flues negatively effect the draft of the stove, especially when the building gets warm and the stove is cut back or not burned as hot? If it makes a difference I was going to put a baffle in the stove so exhaust wouldn't just run straight out.
 

begreen

Mooderator
Staff member
Nov 18, 2005
92,815
South Puget Sound, WA
Two flues are not necessary if the intake is properly sized. A stove like this will likey be woefully inefficient. Sounds like a good way to eat up a local forest.
 

peakbagger

Minister of Fire
Jul 11, 2008
7,121
Northern NH
A home built stove is going to be be un-insurable. Dont do it. Plenty of well built smoke dragons out there that will be far more efficient and safer.
 

begreen

Mooderator
Staff member
Nov 18, 2005
92,815
South Puget Sound, WA
I'd put a wood furnace in a big workspace like that.
 
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brenndatomu

Minister of Fire
Aug 21, 2013
7,081
NE Ohio
I'd put a wood furnace in a big workspace like that.
It would have to be a big mama...like one of the old Yukons, or a Charmaster...too bad they are out of business and parts appear to be NLA. I think Clayton made some pretty large models too...no idea on parts availability on those.
None of the current furnace offerings would heat a space that size (unless you went with 2) sounds like a good candidate for a OWB honestly...just run a short line set into 1 or 2 water-to-air HX's with fan
 

snobuilder

Feeling the Heat
Dec 16, 2021
431
WI
You came to the wrong website for encouragement of any sort of individual innovation. If it hasn't been built commercially and subjected to thorough government agency, insurance company, lawyer and local "professional" scrutiny it will be deemed scary and unsafe.
Much like wearing a MAGA hat in Portland OR.
 

brenndatomu

Minister of Fire
Aug 21, 2013
7,081
NE Ohio
My first question would be, what is the thinnest metal I can get away with using for a stove? I can't imagine the tank is much thicker then 3/16''.
That's pretty thin...better stoves have a 5/16" top...and they are much smaller than what you are talking about...an oil tank might last a season or two, maybe...and depending on how hard it has to be run to do the job....and will likely be a hungry beast too!
 

Ray3

New Member
Dec 26, 2021
3
Maryland
It would have to be a big mama...like one of the old Yukons, or a Charmaster...too bad they are out of business and parts appear to be NLA. I think Clayton made some pretty large models too...no idea on parts availability on those.
None of the current furnace offerings would heat a space that size (unless you went with 2) sounds like a good candidate for a OWB honestly...just run a short line set into 1 or 2 water-to-air HX's with fan
Thank you for the first reply with some actual advice.
 

Ray3

New Member
Dec 26, 2021
3
Maryland
You came to the wrong website for encouragement of any sort of individual innovation. If it hasn't been built commercially and subjected to thorough government agency, insurance company, lawyer and local "professional" scrutiny it will be deemed scary and unsafe.
Much like wearing a MAGA hat in Portland OR.
You're not kidding. I see that.
 

bholler

Chimney sweep
Staff member
Jan 14, 2014
28,189
central pa
You came to the wrong website for encouragement of any sort of individual innovation. If it hasn't been built commercially
You're not kidding. I see that.
subjected to thorough government agency, insurance company, lawyer and local "professional" scrutiny it will be deemed scary and unsafe.
Much like wearing a MAGA hat in Portland OR.
We are just interested in making sure people have the right information so they can make an informed decision about their setup.

Making a stove like this may work but if anything goes wrong you will most likely have big problems with insurance.

Some things are just downright dangerous and in those cases we will tell people flat out not to do it. In this case it may not be dangerous at all we don't know. But there are some liability issues that should be considered.
 
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