I have a Pocono.
Would any of the following be worth the time. Judging by the firebox and flue temp, the stove is already very efficient, but I am wondering if a few hours work might save quarter or half a ton a year.
Would welding on some flat bar inside the stove capture and transfer enough heat to make it worth the time. I am thinking 2 x 1/8 installed vertically 6 inches apart. Downhand weld entire length for surface contact. Same size and spacing on the overhead.
Would welding some flat bar on the outside increase heat output. I am thinking 2x1/8 on top of the fire box, 3 inches apart.
Would welding a 3 or 4 inch pipe (ala the Hyfire pipes) into the unit transfer a noticeable increase in heat output. I would install the pipe from side to side, making the welding access easy from the outside. The way my hotair jacket is set up, with one side of the stove right next to the oil furnace cold air return, the current convection system would draw through the pipe, and continue to draw air over the top of the stove.
I was a certified nuclear and pressure vessel welder back in my boilermaker days, and understand that the unit has to remain air tight.