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There is plenty progress now with the pulley setup for Senegal. The mockup for the well ring, looking like the one in Senegal, gives inspiration. Rogier and I work on 'welding' the wooden sticks together. Once again the choice for details at the moment of actual making is a different one than what I had in mind only a short time before that. And often the difference is big and consists of real improvement.
It keeps surprising me, that such effective solutions can not be designed beforehand. I really thought I did design an effective solution, but practice offers more, much more. It teaches me what I did overlook and it offers far more opportunities than I could have thought of.
Looking back at the whole process of design for the pulley, I think I was right to be challenged by the worn out locally made pulley, laying useless next to many wells, while for lifting water these pulleys were indispensable. That was four years back in The Gambia
The long vision was:
Use locally available stuff to make pulleys in some sort of local craft combined with local trade.
Prevent the wearing out that now destroys the pulleys.
Produce them in an effective way, easy to learn, easy to accomplish.
This long vision was -in my expectation- somehow realistic, because of the worn out rubber tires laying around. It seemed probable that the properties of rubber as well as its round shape would offer a starting point.
Well, it actually did. It did as well offer stiff resistance to let itself shape in something like a pulley. By taking small steps, some progress was gained. What really helped was the interest of Ives Faye for his Keur Moesse project in Senegal. That gave the urgency that I needed to overcome the difficulties I encountered. One of them was bending the rubber in a V-groove like shape and sewing it with bits of wire. An other big obstacle was the way the spokes had to be made. Both problems could not have been overcome in a design made at the very beginning. Only when some of the other problems had found a likely solution, only then these difficult steps could be taken with some result.
Only when the pulley wheel was introduced in the project in Senegal (Februari this year), only then I got some grip on the problem of mounting the pulley over the well. Again the preliminary ideas of how to solve it with concrete and steel melted away at the moment of having to realize them in practice.
Though now there is plenty of progress and the present construction looks realistic, there still is al long way to go. First it has to prove to be functional, to give a real good ergonomic working position for lifting water with two bags. I know such a system can be very effective compared to other ways of pumping water from deep wells. The final test can only be done in Senegal, may be in August or September.
But a harder nut to crack is to create the reserve strength of the supporting construction. The pulley, its axle and the supporting structure have to be strong enough to lift two people out of a well in case of an accident. Such a situation will someday occur. At that time the pulley may not fail to take that load.
When I set out for the design of the pulley I did not have the slightest idea such a demand would ever be made. But it is also encouraging that this extreme demand can -at the very end- be positively answered.
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