I have a Petit Godin that I used successfully for three heating seasons, actually moving it in and out each year from a seasonal rental. Then I put it in storage for two years, and eventually bought a house of my own. I wasn't sure what I was going to do for heat in my new house, which has oil-fired HWBB, and which had a crappy wood stove installed when I bought it. The house has an appropriate flue in the living room, but with an 8" thimble; the Godin has a 5" flue outlet, and in the previous installation I had an adapter to 6" running straight back, inline with the stove's outlet. That arrangement creates too long of a straight pipe run out the back of the stove to allow it to fit in the present hearth setting, setting the stove too far out into the room. I do also have the pipe adapter to step up to the 8" thimble.
I figured out how I could save enough inches in setback by switching to a 5" elbow straight out of the stove. It may actually have turned out to be a false idea, but my fix added a new problem: In trying to pull off the 5" to 6" adapter from the stove's flue, I got frustrated and cracked loose the stove's flue itself. It seems to me to be akin to an exhaust manifold, for whatever that term is worth. So now I have a stove that I think I could install in the location, but I have torn the cast iron flue clean out of the body of the stove. All else seems reasonably good about the stove: some surface rust in the sheet metal cylinder, but I have in the past patched these by using furnace cement like bondo; the firebricks are in good shape, as is the grate, door, etc.
How to re-attach the flue? It look like it was bolted through to the rim, and I can drill out that bolt and re-attach the flue, mechanically. Can I just pack all of that area between the flue pipe and the firebrick and body of the stove with a foundry cement type of material? The fire bricks at the joint all appear quite sound. I can post a picture if that will help. Thanks for any assistance!