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What's new: Tue Jul 01 (2003) An extra function for the pulley support over a well
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An extra function for the pulley support over a well

It is high time to create a consistent idea for the set up of the supporting construction for the pulley over the well. It is not so easy, as it has to be rural technology, meaning it has to be made with next to no tools andd very rough materials.
We do the research in the garden next to our workshop. We made a mockup pf the size and giving the impression of the upper-structure of a well such as at the site of Keur Mousse in Senegal. Experimenting was done by tying bamboo sticks with rubber strips cut from an inner tire.
Today I worked on an added extra design specification; it should be possible to safely lower and lift a man into and from the well. This puts an extra load on the pulley. But for the construction that supports the pulley over the well, it means it now has to withstand a large force sideways, not only vertical because of the weight of the water. This sideways force is generated when a group of people pull together at the rope away from the well. Such a force is equal to the weight of the person being lifted and should not shift the support itself from the well.
To get some grip on how to get it right, Rogier and I made three full size models with bamboo sticks tied with rubber. Our final model, a tripod, will Thursday be composed out of sticks, cut from the bush around and put together with the use of "Welding Wood".
It was high time as well to put the information on the construction of the pulley and the supporting stand on Internet. That is done today as well.


What's new: An extra function for the pulley support over a well
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