After consultation with my financial advisor (aka wife), a neighbor (master welder and fabricator) and many hours of studying the forums here, I have decided to attempt an OWB build.
It's great to be able to see the great work that so many of you have done here, get ideas, and maybe avoid some pitfalls along the way.
I have attached a preliminary drawing .pdf to this post, please check it out. I'm sure a lot of the dimensions will change somewhat, but it will give you a pretty good idea of where I am headed.
Outer water jacket tank is a propane tank, 41" O.D. x 79" long, 360 gallon capacity. One of the half-sphere ends will be cut off, flat plate will be welded to that end to accomodate the 20x20 door opening.
The firebox will be 30" round piece of propane tank (with a section cut out full length on the bottom and flat plate welded in) x approximately 48" deep.
Water capacity should be somewhere around 160 gallons when completed.
Flue will be 6" Sch40 steel pipe, it will extend about 12" into the firebox and exit horizontally into the water jacket, then I will go vertically with more 6" after it exits the water jacket. The horizontal piece will extend outside beyond the flue and have a cap, to access the horizontal tube for cleaning.
Door will be a pre-manufactured 20" x 20" unit with draft induction fan built in.
No ash pan, no grate.
1" bungs will be provided on the back end of water jacket, from top to bottom: 2 for return, 2 for drywell (aquastat) or thermometer, 2 for supply. Returns will be extended up high to be near the front of the tank, supply will be drawn from down low and near the back of the tank. A 1 1/2" or 2" outlet will be provided on the bottom for tank drainage.
A 2" threaded bung already exists in the middle of the top of the water jacket, for fill point, venting, water level float....?
This whole assembly will set up off the slab on a metal framework, and eventually all will be enclosed/insulated in a metal framed and sheathed structure.
All comments/thoughts/suggestions are welcomed!