Forced air wood burning stove

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Approx 22" wide, 2' tall, and 4' long.  The base is a drop of W21x73 I had laying around.  Dont see the bottom rotting out anytime soon.  Still have to build the door and dampeners on each side of the door, but its in pretty good shape.  Top is cut, ready to go on.  I have a 240v fan that I may use for this, but am going to look for something else a bit more quiet.  The square going in the rear is 4"x4"x1/4, into a 6x6x1/4 plenum with 1 1/2" std. pipe 90* from entry and out the front.  All the 90* bends are on purpose for heat exchange.   I will update further when I am done.  Lots of toys.
Reply:what would work real well is a 5" round duct fan you can buy at the hardware store there about $35 and ment to take a little heat and very quiet they move 225CFM ( there ment to boost the air in a remote duct or one that needs extra movement.)
Reply:Looks like it should produce and distribute a lot of heat!  In the old days a similar design had water flowing through the pipes.Check here for blowers:https://www.surpluscenter.com/sort.a...&search=blower,I just installed a wood burning stove in my shop and it works quite well.  Based on my recent experience I'll offer, for what they are worth, a few observations - thought you've probably already thought of them.1. You might think about adding a outer wall (making it a double wall) on the back and sides with an air gap of an inch or two.  This will help prevent igniting anything in close proximity and allow a much smaller stove to wall clearance.  Otherwise the 'code' will require at least 36" from any wall not designed specifically for fire protection.  On my stove the outer wall is only 16 guage sheet steel and it works great at keeping the heat off the wall. This still allows for radiant heat from the top and sides as well as from the air flow.2.  Your probably already going to line the stove bottom with firebrick or refractory cement but I would also consider lining the walls about half way up with fire brick as well.3.  With a stove this size I would think that you might consider an 8" chimney with 6' being the smallest.  I learned that larger and longer (12 ft) of chimney draws best and that double or triple insulated chimney is required to go through ceilings/roofs.4. For chimney/stovepipe check craigslist FIRST!  - This alone saved me $1000!
Reply:I have thought about building one using the pipes as heat exchangers...similar to this stylehttp://stoveworksusa.com/24-36-2.html  (my wife likes the stove model)I would put a bigger door and 1/4 steel.  Yours has a big enough door and nice welds.
Reply:Thanks for the replys.  One thing I flat dorked out on is an insulated rear wall.  That will help the fan in the long run.  I am still going to put a 1/16" piece of steel over a 5/8" sheet of durarock as a thermal barrier for the wall insulation.  I am not concerned with codes as I am in a rural area in my shop which is not subjected to any city jurisdiction.   Only county semantics.  I do not want to insulate anything other than the rear wall for the radiant factor.  The shop is large enough that keeping a 5' buffer on each side isnt a problem.   I am not going to put any masonry liner on the interior either.  The base of the oven is the web of the 21x73 which is 3/8" or 7/16" and the flange that comes up 4" is 3/4".  So I figure when my dads 50 year old cast stove with 3/16" wall all around is holding up fine this will be ok.  Especially how much I am into it cost.  Basically all drop material, some solid wire, argon, and electricity.   BTW, my walls are 1/4" and top is 3/8".   This isnt something that will be used more than 30 days a year roughly.  Its the Dallas Texas area and frankly all we want to do is supplement the propane heaters to make the shop tolerable on frigid days.  Its nice to have a shop that is 25' tall at certain times.  Heating it is surely not one of them.Lots of toys.
Reply:I am still going to put a 1/16" piece of steel over a 5/8" sheet .......
Reply:With regard to the suggestion of firebricks, and whether to use them or not. I know of at least one 55 gal drum wood burner that is in the neighborhood of 10+ yrs in service, and I built one for my garage/shop that is going on 5 or so years, and have no problems. The trick is simple. Just leave enough ash in the bottom to protect the steel from the direct heat of the coals. Especially for something that you don't use alot the bricks aren't needed. I do have the floor and sides lined in the stove that I heat my house with every day, and it is nice to be able to scoop all the ash out.
Reply:Originally Posted by mrmikeyNot sure if you know or not but make sure you leave a 1" air space between the sheet metal and the drywall as well as leave it up off the floor an 1" as well. This allows air to flow via convection to pull the heat away. If you mount it tight it'll just act like a pan on a hotplate and transfer the heat to the wall.BTW, nice stove. I'd build one for the garage I just built but if it's not CSA or ULC or something-or-other certified woodstove the crap you have to go thru for insurance does not make it worth while.....Mike
Reply:Here is where I am today.  High volume (fairly low rpm) blower motor.  I actually got one smaller as well, but it turns very high rpm and in turn is much more loud.  Added a propane rose bud type orifice on a 1/2" pipe for lighting the fire.  The heat shield you see here is what I cutout for the door to aid in protecting the blower.  I dont feel like going back and putting a whole sheet across the back.  BTW, air distribution is uniform and just what i was looking for.  When standing 5 feet or more in front of the stove I can barely hear the fan.  Yet it still moves plenty of air.  Hope to have time enough to get it close to done tomorrow.  Lots of toys.