bigegg
Scream Not Working Because Space Make Deaf
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- 9,488
- Location
- Leeds, West Yorkshire
Following on from my post in the "woodstove thread", I thought I'd share my build of a self-designed woodburner to heat my new work area.
My basic idea is to use the principles of a "rocket mass heater" and the research done at aprovecho to make a super-hot efficient woodstove.
I sourced [1] a 6ft(ish) piece of 8" ceramic drainpipe today, so that is going to make the burn chamber. I've been using a 2ft piece of the same stuff as a hot wall in my furnace for the last three years, so I'm reasonably certain it's going to stand up to the temperatures.
I'm going to mitre the drain pipe into a "J" shape - 8in vertical into 24in horizontal into 4ft(ish) vertical - held together with fire cement. This will be inside a "J" shaped assembly made from gas cylinders. The void will be filled with insulation - probably vermiculite + fire cement, but possibly one of the other insulation recipes from backyardmetalcasting
or some kaowool insulation (but I'm hoping to save that for my next furnace).
Suspended around the outside of the "chimney" (long side of the J) will be an inverted 200L oil drum which will act as a heat exchanger. The hot air from the burn furnace will blast against the base of the drum and then flow down the walls of the drum, and then out of a 6inch (8in maybe) pipe to the outside world.
I've got a feeling that the base of the drum is going to burn out within a month or two [2] so I have plans to replace the base with a cast iron plate, or piece of 10mm+ road plate. Alternatively, (additionally) I may cast an aluminium heatsink and blow air across it via a bouncy castle blower
[1] from a road maintenance crew at the end of my street
[2] based on the non-insulated prototype.
My basic idea is to use the principles of a "rocket mass heater" and the research done at aprovecho to make a super-hot efficient woodstove.
I sourced [1] a 6ft(ish) piece of 8" ceramic drainpipe today, so that is going to make the burn chamber. I've been using a 2ft piece of the same stuff as a hot wall in my furnace for the last three years, so I'm reasonably certain it's going to stand up to the temperatures.
I'm going to mitre the drain pipe into a "J" shape - 8in vertical into 24in horizontal into 4ft(ish) vertical - held together with fire cement. This will be inside a "J" shaped assembly made from gas cylinders. The void will be filled with insulation - probably vermiculite + fire cement, but possibly one of the other insulation recipes from backyardmetalcasting
or some kaowool insulation (but I'm hoping to save that for my next furnace).
Suspended around the outside of the "chimney" (long side of the J) will be an inverted 200L oil drum which will act as a heat exchanger. The hot air from the burn furnace will blast against the base of the drum and then flow down the walls of the drum, and then out of a 6inch (8in maybe) pipe to the outside world.
I've got a feeling that the base of the drum is going to burn out within a month or two [2] so I have plans to replace the base with a cast iron plate, or piece of 10mm+ road plate. Alternatively, (additionally) I may cast an aluminium heatsink and blow air across it via a bouncy castle blower
[1] from a road maintenance crew at the end of my street
[2] based on the non-insulated prototype.
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