Rocket stove

Rocket stove with heat storage to heat greenhouse

Rocket Stove

Home made rocket stove storing heat by running the flue through a brick and gravel channel

rocket stove bricks1

The first layer of bricks (red bricks from a skip) set on a series of concrete slabs. The bricks for the firebox and barrel are raised off the floor on steel channel and Rockwool to keep the heat from the floor.

The Stove components are ; A 2 ft cylinder cut from an acetylene bottle and a bottle gas bottle (do take great care if you do use either of these cylinders - danger of lethal explosion!) You need to remove the valves and fill the bottles with water to ensure there is no gas left in the bottle.
Ordinary house bricks (out of a skip)
About 4 foot of 7 inch flexible stainless flue liner (out of a skip) Fire clay (from eBay)
Bits and pieces and a frying pan for the lid of the firebox.
The internal flue pipe is single skin steel (scrounged) and the outside chimney is twin wall stainless flue (from eBay - not cheap but take your time and you can find bargains.
The heat storage is made by building a brick wall next to the indoor part of the flue (runs along the whole length of the greenhouse floor) and filling the gap with gravel and concrete

Picture below shows:
Outer barrel cut from a gas bottle showing the cut away where the flue will join and cylinder cut from an acetylene bottle. The inner insulated barrel was made from flexible stainless steel flue liner.

Second layer of bricks showing firebox and the foundation for the inner and outer barrel. I modified the firebox to enlarge it later.

Rocket stove barrel and cylinder

Rocket stove barrel

Looking down inside the gas bottle barrel showing the inner barrel of stainless flexible flue pipe which is insulated with ceramic fiber insulation (I had in the workshop but available from eBay) then the acetylene cylinder then a gap and lastly the gas bottle

bottom of barrel

The hole cut at the base of the gas bottle to allow the flames to travel out to the flue pipe

Carefully shaped piece of flexible flue pipe to bridge then gap from bottle to flue. The whole assembly covered with a mix of sand , cement, and fire clay