On Sunday September 08 1996, Alec Cameron of (3:712/517.12) wrote to Chris 
Harper:
 AC> On (30 Aug 96) Chris Harper wrote to Alec Cameron...
 CH>> convert an old lawn-mower motor into a steam engine. Sounds a lot
 AC> Four stroke of course!! A two stroke conversion might need some 
rilliant
 AC> design work.
Actually, a 2 stroke would be easier, depending on the type.
 AC> Steering those mirrors will be a design problem. You'll have to decide
 AC> whether to have "auto pilot" ie the mirrors move almost non stop in two
 AC> planes, or use a simple rotational drive that you reset every few weeks 
to
 AC> suit the seasonal changes in sun elevation. A lot of your collected 
energy,
 AC> should not be consumed in auxiliary loads like mirror steering and water
 AC> pumping.
I intend on having all the mirror clusters drives linked, and use a single 
sensor/drive mechanism for each axis of control. The sensor will feed a small 
z-80 computer which will control the locking stepping motors I use to drive 
each axis.
This should give very precise mirror alignment without to much power 
consumption from constant drive adjustments. The frequency of the adjustments 
will be controlled by the sensitivity of the sensor, which will be mounted on 
one of the mirror clustors. Of course, the focal point will move more when 
the sensor isn't set real sensitive. All I need to do is find a "sweet spot" 
in the setting, where the movement isn't to great, yet there is a fair 
interval between movements.
 AC> High temperature melting, is one of the main jobs of three large solar
 AC> furnaces in France. If you have "Public TV" ie non - commercial, then 
watch
 AC> for a series called Fat Man In France.
I'll watch for it. Thanks!
 AC> Protective goggles very! necessary. Do not look at the bright spot with
 AC> unguarded eyes.
I've got welder's goggles already.  ;-)  Also welder's gloves in case I need 
to make adjustments to the primary collector while running.
RYL,
    Chris
--- GoldED 2.40+
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