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</o:shapelayout></xml><![endif]--></head><body lang=EN-CA link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='color:#1F497D;mso-fareast-language:EN-US'>Dear Vincent<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D;mso-fareast-language:EN-US'>It will help a little. What would really help your overall fuel consumption however, applies to all stoves of this type which have a flat bottom and no grate.<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D;mso-fareast-language:EN-US'>Put a metal grid grate at the bottom, elevated perhaps 10-15mm. That takes up very little vertical space. The grate can be reused if the clay is exchanged, or replaced if it wears out.<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D;mso-fareast-language:EN-US'>Try this: Use straight 12mm round bars. The spacing of the bars should be 16mm centre to centre. This is a lot more bar material than one is usually offered and there are good reasons for that. Make it the same diameter as the hole, minus a bit to drop it in easily and either provide a mud/clay ridge around the bottom to elevate it or give it a few short feet.<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D;mso-fareast-language:EN-US'>Then use the stoves as normal. What you are looking for is clear evidence of the production of less charcoal. If the char has support from below, it will burn properly instead of smouldering in the accumulated ashes. It can increase the total heat available by as much as 25% in a typical cooking cycle. The gap under the grate provides for an element of preheating of the primary air which increases the completeness of the charcoal combustion.<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D;mso-fareast-language:EN-US'>Whether the bottom is made of ash or loose-but-packed clay will make little difference to anything.<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D;mso-fareast-language:EN-US'>Regards<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D;mso-fareast-language:EN-US'>Crispin<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><span lang=EN-US>Hi.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>Could anyone help me out with this - would an ash layer beneath a fire in an improved cookstove (as in the sketch attached) help insulate the fire and prevent heat loss into the body of the stove? The layer would be about an inch thick after compression, and is about half an inch below the base of the stove.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>Thanks,<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><b><span lang=EN-US style='font-family:"Graphite Light ATT"'>Vincent Okello</span></b><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'><o:p></o:p></span></p></div></body></html>