If you are stiring in the pot and there is any danger that food drops out of the pot, then turn up the mirror to remove it from under the pot (like shown on this picture). After usage turn the mirror completely up so the mirror face looks to the ground and the cooker looks like a mushroom or an open umbrella. All rain wil hit now only the back of the mirror and no dust will collect on the mirror. First pure a lot of water over the upright mirror to wash any sharp san partilcles from the surface.
Containing many detailed construction-plans). An other source of pdf-files on Solar-cooking. You may find here on GoGetPapers. And yet an other source of pdf-files on Solar-cooking. Word-doc-file: Improved Cook Stoves Manual, Peace Corps Bolivia, November 2008. And here you can download a little booklet in German language from the "Landesanstalt für Umweltschutz Baden-Württemberg" about experiences with German solar projects in Afrika (containing a short statement about AMSI):. Improved Cook Stoves Manual.