Stirling Engines
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Updated 23 Oct 2007
Stirling engines, named for it's inventor, Sir Robert Stirling, are
called external combustion engines because the pistons and
cylinders are sealed from the outside atmosphere and the heat
is applied to the outside of the piston (called the displacer). It is
a very efficient engine which many have tried to use
commercially with little success. Probably because it does not
have much torque.
This is the Stirling engine that I built.  
The displacer piston is the large flat
area just below the  wheel.  The
power piston, made of graphite, is in
the small brass cylinder to the right of
the fly wheel, sitting on top of the
displacer. The displacer piston is
made from plastic foam and is very
lite.   The engine is supposed to run
by  heat from the palm of your hand or
by placing it on top of a hot cup of
coffee.  I still need to tweak this
engine to get it to work correctly.  It
almost looks like a piece of jewelry!
This is a Walking Beam Sterling engine that I
completed on 1 Mar 2006.  It was made from
plans from 'Little Workshop' and required that
almost every part be made from scratch.  It runs
very smoothly.  I made it using my lathe and mill.
Click on thumb nails to enlarge
I bought this old Stirling engine (late
1800's-early 1900's) in Ruidoso,NM in 2003.  
I  cleaned it up and did some minor
reconstruction but it is essentially the
same as when it was new.  The silver
colored tank holds water for cooling the
displacer piston (the round brass object in
the center with tubes running to the silver
tank).  The power piston is the small round
brass object to the right center.  The boiler
looking object to the left has no function.  
Inside this boiler looking object is the end
of the displacer piston where heat is
applied either by a candle or a small
propane flame.  This engine runs very well.