Crispin, Thanks for that, I have the balding scarred noggin' to proove the experience at least...
On the drum crusher, several have proposed the idea on this very list many years ago. Some even proposed the use of rods instead of stones ... I tried the idea out, albeit haphazardly, by partially filling a 20 liter paint tin with coarse sharp edged rocks and chopped ag residues simply rolled around on the ground.... I found it abit slow, although it did manage some degree of pulversiing. Certainly the greater falling velocities of the stones in the a full sized drum --augmented perhpas by weights about the circumference of the drum to create a flywheel effect, to smooth out the ovalised power output of the hand cranking motion--might produce far better results. I am sure the concept, if workable, would be most welcome by all concerned. One big issue lingers though: That is the need to size the material before you attempt to smash and flay it out. Some favor separate functions in all these machine concepts : a chopping, then the threshing mashing operation. Others including myself favor a combined one step machine for preparing materials... Viz., the feed opening could be fitted with knives rotating against a fixed anvil on the frame /stand but that would necessitate centering the rotation for the drum on its central long axis--It ould be a step away fomr the classic cement mizing drum design with its offset long axis found so effective for tumbling and thorough mixing of - at least- cement. Then again consider rock tumblers, most all of which operate on a central non wobbling axis eh ? While our own solution , our Thresher Masher Chopper, viz., the "TMC"(see our website) does all of that well, it runs on a fine tolerance and it is neither cheap nor easy to build, outside a well managed, workshop of the sort usually found in the larger cities. More recent changes in the fabrication process now allows fabrication one-off TMC's in smaller shops but it is certainly not something that the street 'jua kali' fundi/artisan..could normally handle : And that is the ultimate level at which the technology needs to be embedded, to assure its self sustaining growth. So please Crispin et all, dive in and lets see what we can do collectively; It remains the efficient processing of biomass at the manual level --and not the pressing ---that limits efficient agroresidue based briquettemaking where it is most needed, globally. Richard Stanley www.legacyfound.org NW Obamaland On Jan 28, 2011, at 8:44 PM, Crispin Pemberton-Pigott wrote: > Dear Richard > > Much wisdom and experience and technical information in that post. Well > done. I am looking forward to seeing the concrete grinder/masher. Anything > made of concrete (including stoves) is cheap. > > Have you considered chunking, soaking and then placing fuels into a concrete > mixer with stones in it? It is quite easy to turn a hand operated concrete > mixer with 150 kg of materials in it. I am thinking of something like 50 kg > of 40mm sharp, crushed stones and 100 kg of chunky material. > > Only one moving part, makeable, could even convert oil drums. > > Regards > Crispin > > > > _______________________________________________ > Stoves mailing list > > to Send a Message to the list, use the email address > Stoves mailing list > > to UNSUBSCRIBE or Change your List Settings use the web page > http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists.org > > for more Biomass Cooking Stoves, News and Information see our web site: > http://www.bioenergylists.org/ > [email protected] > http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists.org _______________________________________________ Stoves mailing list to Send a Message to the list, use the email address Stoves mailing list to UNSUBSCRIBE or Change your List Settings use the web page http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists.org for more Biomass Cooking Stoves, News and Information see our web site: http://www.bioenergylists.org/ [email protected] http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists.org
