Introduction: Wood Stove Flue. Upgrade to 5", Resolving Some Problems + Home Made Fan Bellows.
This is how I replaced and up graded the old 3" flue that was weld together and eventually grew up with junk and became so clogged up that it had to be remove and replaced with a 5" flue.
The new flue was made of in 2 sections, each about 6 feet long and 5" in diameter the top part was part of an old traffic sign and I bought a piece to match from a local steel works. I made some brackets from flat bar and some cutting of 6" hoops I found in one of the old sheds. I had to make an adapter to match the stove with the new flue. a hoop was welded to the end of one pipe to act as a socket for the top pipe. The whole thing worked fine with no smoke leaks and i was happy to have the stove going again
The old flue pipe could only be clened by going onto the roof of the shed and using a rod to push the stuff down, an accident waiting to happen so I chose a 2 part flue so that if it did ever get blocked again it could be taken apart for cleaning with no need to go onto the roof.
I actually installed this flue just over a year ago and due to the insulation I added to the roof of my shed I have not had the stove lit all that many time since.
Yesterday I went out to work in the shed for a bit, it was cold and i would have needed the stove lit but I found that the flue had separated due to the pie expanding and pushing the pipe up in the brackets, but due to the brackets being clamped to tight they would not let gravity drop the pipe back once the flue cools down and contracts again. The flue had finally pushed the top section up so far that when the bottom pie cooled the pipes had disconnected, on inspection the concrete slab that the stove was sitting on had cracked and the stove had moved as well, so it was time to sort out these teething problems.
The flue is I about a year now and is showing signs of wear and weathering, the rain come down the pipes even with the rain hat on and the steel rusts no mater how often i repaint it with heat proof paint.
I removed the concrete slab and realigned the stove in position, I then slackened off the top brackets so the top section would drop down into the socket on the bottom section. I then used some 3" angle bracket to clamp the base ring of the stove to the floor so the stove will not have any chance of moving out of position.
This new 5" flue works a treat, it acts like a giant radiator and combined with the 1" polystyrene sheets I fitted to the roof I find that I often have to open the door as the heat is almost unbearable now, and that once lit a single fill will keep the shed toasty warm for hours, I have burned hardly any wood at all this year.
As bonus I have shown a few pics of a makeshift fan bellows that I knocked together to assist lighting the stove.
Thanks for looking.