Two cylinder high speed steam engine

Les Kerr in Australia designed this two cylinder high speed steam engine; it was based on a single cylinder version by Colin Andrews. The valve action is performed by cutting grooves in the pistons and rocking them sideways at the same time as they move backwards and forwards. These grooves line up with the steam inlet and outlet ports at the correct time. The construction of the engine was serialised in Model Engineer beginning with the 22nd August 2003 issue (Vol 191 No 4202) under the name of Twin Cylinder Twisty