Post by oddball on May 1, 2012 11:55:35 GMT -8
Hello all,
I'm based in Johannesburg, South Africa. Last year I built a rocket stove at the end of our winter (was fed up with being cold!) and now I am working on it again- who wants to make fires in summer! :-)
The problem is that my stove does not draw well at all and my house fills with smoke every time I try it out.
I'm using a standard 44 (or is it 55?) gallon drum (the ubiquitous fuel drum) for it and the heating pipe/exhaust/ flue is 25.6 feet long.
The system dimensions are (these may seem odd- because we speak Metric here I have changed them to Imperial dimensions for those of you metric-challenged types ) :
Feed tube: 6.5"x 5.9" by 7.7" deep/ high, Area=38.4 Sq"
Horiz burn tunnel: 6.5" wide x 4.5" high, Area=29.5 Sq"
Heat riser tube (round): 6.5" ID, Area=33.2 Sq"
Exhaust/ horizonal flue: 7.9" ID, Area=48.6 Sq", length 25.6 feet
From Ianto and Leslie's book the dimensions seem OK in that the smallest area is the burn tunnel. Here are the issues that I think are of consequence:
1. I don't have a vertical 'chimney' at the end of the exhaust; the exhaust exits about 1-1.5 feet below the burn tunnel level.
2. The issues that Donkey described in his helpful hints, where the exhaust gathering area is detailed, may be too small. In my stove its not easy to measure (odd shape) but it does drop into a big ash pit.
3. Perhaps my feed tube is too big?
4. My heat riser tube is 38.8" high but 4.5" from the top of my barrel. I made the 'imaginary cylinder' (as described by Ianto's book, labelled G) very large- partly because of materials on hand...
5. The average gap between my barrel and the insulated heat riser is 2.7"
The critical questions are:
Is the G area (point 4) critical? I thought that it should not be too small and too big was not a real issue, so I made it big. Site recomendations say that i should be 1.63" high, but mine is 4.5" high. Should I make it smaller?
Is the vertical end chimney (at the end of the exhaust) vital?
Is my feed tube too big?
If you answer you'll get at least 1 or 2 free nights accomodation in Johannesburg (which seems to be fast becoming a worldwide metropolitan sexy city- I do love staying here!)
South African Jay
I'm based in Johannesburg, South Africa. Last year I built a rocket stove at the end of our winter (was fed up with being cold!) and now I am working on it again- who wants to make fires in summer! :-)
The problem is that my stove does not draw well at all and my house fills with smoke every time I try it out.
I'm using a standard 44 (or is it 55?) gallon drum (the ubiquitous fuel drum) for it and the heating pipe/exhaust/ flue is 25.6 feet long.
The system dimensions are (these may seem odd- because we speak Metric here I have changed them to Imperial dimensions for those of you metric-challenged types ) :
Feed tube: 6.5"x 5.9" by 7.7" deep/ high, Area=38.4 Sq"
Horiz burn tunnel: 6.5" wide x 4.5" high, Area=29.5 Sq"
Heat riser tube (round): 6.5" ID, Area=33.2 Sq"
Exhaust/ horizonal flue: 7.9" ID, Area=48.6 Sq", length 25.6 feet
From Ianto and Leslie's book the dimensions seem OK in that the smallest area is the burn tunnel. Here are the issues that I think are of consequence:
1. I don't have a vertical 'chimney' at the end of the exhaust; the exhaust exits about 1-1.5 feet below the burn tunnel level.
2. The issues that Donkey described in his helpful hints, where the exhaust gathering area is detailed, may be too small. In my stove its not easy to measure (odd shape) but it does drop into a big ash pit.
3. Perhaps my feed tube is too big?
4. My heat riser tube is 38.8" high but 4.5" from the top of my barrel. I made the 'imaginary cylinder' (as described by Ianto's book, labelled G) very large- partly because of materials on hand...
5. The average gap between my barrel and the insulated heat riser is 2.7"
The critical questions are:
Is the G area (point 4) critical? I thought that it should not be too small and too big was not a real issue, so I made it big. Site recomendations say that i should be 1.63" high, but mine is 4.5" high. Should I make it smaller?
Is the vertical end chimney (at the end of the exhaust) vital?
Is my feed tube too big?
If you answer you'll get at least 1 or 2 free nights accomodation in Johannesburg (which seems to be fast becoming a worldwide metropolitan sexy city- I do love staying here!)
South African Jay