MM16 - The LEHMANN engine

Technical dedails
Year of construction 2001
Power piston stroke 20 mm
  diameter 20 mm
Displacer piston stroke 40 mm
  diameter 20 mm
Flywheel  diameter 100 mm
  material PMMA
Idle speed 280 rpm
Energy source alcohol
Mass 460g 


Lehmann engine, second attempt. This time, I again intended to  achieve transparency and a bigger accordance with the original engine. The water cooling is realized by a closed jacket surrounding the displacer cylinder completely. Both parts are joined by screwing at the rear end, and at the front they are sealed by an embedded rubber ring. The big acrylic parts requiered special care  during processing. Although I had annealed all parts before gluing,  some tiny tension cracks appeared. For mounting the engine I used a special glue named ACRIFIX (available at Opitec).
"Hei▀luftmotoren VI", by Udo Mannek; (Neckar-Verlag Villingen-Schwenningen; 2000 ISBN: 3-7883-0667-x)