alt.energy.renewable

/watch?v=wjY2fHR-pdg
I have used a couple of "mathematicians" to make cardboard pannel and cob
parabolic solar cookers. It might be useful if other people try it too.
Parabola cookers are traditionally hard to make and the process goes,
mathematician in an office, hands off the plans to metalworker in a
metalshop, who makes a template that is used to form sheet metal into the
solar oven which is then sold to the user.
The "mechanical mathematician" way goes as follows. Local person constructs
the mathematician with movable focus and uses the mathematician directly to
guide him or her in making a parabolic dish "or dome for casting"
Aluminium kitchen foil is stuck directly to the cardboard, mud or whatever
substrate is used bu the user.
I think the "mechanical mathematician" is probably appropriate in lots of
situations.
Brian White