This is a small solar model based on the 'Moving Cylinder' approach of the MC_Solar. The major difference to the MC_Solar is, that this model has no pivot in the middle. It is mounted on springs (majorly acting like torsion springs) at one end of the cylinder (box) and swinging on the other side. Although, as all of my model, this model (as the picture tells) is simple and diletantic built, it start swinging with only 1/4 of its surface exposed to sunlight. Its average speed is about 55 strokes a minute.
Here some technical detail and hints for builders:
Cylinder(box)'s size 110*110*30mm
Cylinder springs 1mm steel (piano wire) mainly acting like a torsion spring Side walls made of plywood 4mm Cold back plate 115*115*1mm aluminum sheet Displacer made of Balsa wood, turning in a small angle with a tangential stroke length of 15mm, 15mm thick, black painted Displacer spring: 0.5mm steel (piano wire) Displacer's extra weight: 10 gram washer Diaphragm fixed piston: 15mm diameter Diaphragm made of a children ballon 30mm diameter
See a little drawing
Side view
Front view
AND !!! HAVE A LOOK AT Martin Wyss's (Switzerland) big (500*500mm) MC_Solar using springs.
It's reported, that it runs a 100 strokes a minute.
...and it's Swiss made, so it's more accurate than mine !