I’m wondering if anyone has done work with manual powered grain mills? Particularly, grain mills for maize or sorghum that could be powered by peddling a bike, similar to this example. All the better if a design is available and if it is readily reproducible in low-tech contexts…Thanks!
Here is a link that might be helpful. Perhaps the motorized option could use a bicycle setup instead.
Thanks for the great resource, Robert! I have added this to ECHOcommunity.
I always caution people to temper their excitement over technological solutions until the devices are properly vetted among the target population. Unfortunately there are many impressive appropriate technology devices, including human-powered machines, that never get put to regular, practical use. In my experience, community members may enthusiastically welcome someting new but then never utilize it. Maybe you have already tested this idea among your target community, and if so, I salute you.
While there have been some good resources and advice already shared, I thought I would post a few pictures of our pedal-powered mill. While there could be some improvements made (mounting to a sturdier frame, reversing the seat and handle bars, etc), it is a fairly simple set up that can be done without a lot of metalworking. I recommend leaving the sprockets and derailleur on so each operator can find the speed:torque ratio that works best for them. While it still takes a lot of time and energy to use a pedal powered mill, I find this technology helps alleviate the drudgery.
I hope this helps. Please post some pictures of your final product if you decide to build one!!
FYI. CTI will no longer have/or sell the grinder. We bought one last week and there were only 2 left. From what I understand they are looking for a company in a developing country to produce them.