Custom Baffle Plate For Old Boxwood Stove?

Just picked up an old USSC 2421 Logwood in excellent condition for my shop. 28' stack straight up through the building with exceptionally strong flue draft. Those familiar with the design will know there's really no way to completely dampen the air flow unless the slot under the door and slots in the hearth plate are somehow covered. I use a firebrick over the hearth plate slots for now and intend to fashion a skirt of sorts out of some fiberglass gasket roping for the slot under the door to try gaining some better air management with the flow control knob on the door combined with the flue damper itself. It's slotted (the flue damper) and doesn't completely close but should be much more effective if I can otherwise reduce the incoming air as described.

Since these designs are about as wide open as it gets and can run away quickly if not properly attended to, and since the flue temp gets very high very fast simply on fire up, my question is..., has anyone come up with a simple modification to add a baffle plate just below the flue opening running forward -- say halfway to the door -- to divert the direct airflow up the flue forward and back again so as to keep more heat in the stove while also achieving less direct contact between the flame and the single wall pipe? I'm not talking about trying to achieve secondary burn, but just trying to divert the gasses to lower the flue temp so the stove itself can heat up a lot more before I need to choke it back just for the sake of the flue temp..., and hopefully save a lot of wood in the process. It's just burning too hot and too fast as it is right now.

I was thinking of something along the lines of a piece of sheet steel simply attached to the bolts on the underside of the flue collar (with spacers) to create an inch or two airspace forcing the air flow forward and around the baffle before it could reach the actual flue opening. Maybe some bolts through the sides or bracket plates from the top for additional support. I believe they try to do something like that now with the super cheapie boxwood styles being sold using a ceramic blanket / fixed damper approach -- which evidently just chokes the stove and needs to be removed for any flow whatsoever anyway from what I've read.

The only concern I have is whether or not the diverted airflow will try to exit via the cook top area. Seems like with enough draft it shouldn't be any more of an issue than it is now, which is none. And it's ironic that most complaints I've read about these stoves are based on smoke coming out everywhere else except the chimney because they draft so poorly.

And just for a little background, I've been heating with wood for years and also have a Napoleon 1401 insert for my primary heat source along with an infamous USSC Hotblast 1547 for the single digit and below stuff. Have zero complaints and/or problems with either one and actually like the 1547 despite all the grief I see folks given' em. Will probably replace this boxwood next year, but the price was right this year and I jumped on it. Still plenty of cold ahead and I want to get my money's worth out of it yet this year without burning up all of next year's wood!

Sooooo..., has anyone tried anything like this for these old boxwood designs or have any other creative ideas?
(No barometric dampers, please.)

TIA for any input or enlightenment.

 

As far as ease of application if you have a welder or access to one why not just weld a few pieces of angle iron to the inside of the box and slide a piece of plate steel onto to the angle and back against the back of the box.

 

I lack both the welder and the skill set, but the approach would certainly be a better one than using stainless nuts and bolts. On the other hand, I've heard that welding cast iron isn't the easiest thing to do, either. Could be all wet there, but just recently had a discussion with the guy who does lots of chimney work in the area who claimed he couldn't find anyone to weld a crack in a cast iron stove he was trying to sell. Said something about needing to get the iron to some ridiculous temperature before even attempting to apply a weld. Hell, I dunno. That's just what he said. LOL

But thanks for the response. I would certainly prefer to do it all internally than drill holes in the casting.

 

Ah I was thinking it was a steel stove. Cast iron does complicate things. So you are left to drilling for bolts or could you possibly lose a little inside fire box space and stack a few firebricks on the sides and back to set a steel plate on.

 

I thought about the firebrick too, but the sides of the stove are curved and wouldn't provide much stability for a baffle without some type of retainer for the brick itself. Could possibly try it just for proof of concept to see how the flame reacts to the diversion. May have enough brick. Could use the bolts/screws that are already holding the flue collar in place for a small plate, too. Maybe firebrick to support the just the front sides...

 

Here ya go.

It's a basic boxwood design. Firebox is 31L x 16W x approx 18H. I attempted a fire brick support arrangement for a plate I have that is almost the correct size but it was too unstable due to the curved sides. A few pics for any ideas anyone may have, though I think the simple approach would be to suspend a baffle plate using extended flue collar bolts at the rear and to drill a couple holes for two more bolts toward the front with some fashion of standoff to create a 1 or 2 inch air space. Not sure about the best way to drill cast iron. I'm guessing "slowly".

I'm thinking a plate extending about halfway into the cook top area from the rear should suffice...maybe a little longer. Using bolts to suspend it would certainly allow for experimentation with the positioning for the best result.

Generally desired position of the baffle for starters...


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Another thing that jumped out at me regarding the excessive draft supplied by the opening under the door and the slots in the hearth plate is to just use ashes to block to openings so the damper knob in the door itself can be more effectively used to control the air along with the flue damper. Probably how it's supposed to work anyway. Curious if anyone actually knows.

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