Farm Boy is a bar stock engine requiring no expensive castings
but is designed to look as though it was made from castings. As
seen above, it is not possible to know it was made from bar stock.
It is mostly aluminum alloy which is much stronger than castings
and machines better as well. As a hit-&-miss type engine it
needs no cooling system and will operate for long periods on a
small amount of fuel. Running time is 12 hours on 2 ounces (59cc)
of fuel. Even after all day runs the engine only gets slightly
warm. The engine is not difficult to build, yet offers some interesting
challenges to keep an experienced builder interested. Farm Boy
is designed to use an "O" ring on the piston instead
of normal cast iron piston rings (the builder can use cast iron
rings if desired). This results in near perfect compression from
the first run and because there is very little cylinder friction,
Farm Boy will coast from 20 to as many as 30 revolutions between
firing.
The plans set consists of 19 sheets of quality laser printed CAD
drawings and 2 sheets of construction notes.