First Flip Face prototype for members to download and try.
This is a successful mechanism. Turn the handle on the back of the box a full turn and the face turns 180°. The mechanism keeps the face in position when it is supposed to be stationary. The only downside I see is that turning the handle a full turn then stopping isn’t the obvious thing to do. Ah well, you try it and see what you think.
Print out the parts onto three sheets of thin card (230 microns / 230 gsm) Score all the dotted lines, cut out the holes the carefully cut out the pieces. Dotted lines are valley folds, dashed lines are hill folds, solid lines show where to cut. Fold up and glue together the side pieces making right angled triangle sections top and bottom.
Glue together the drive stiffeners.
Glue the drive stiffeners to the drive wheel on the grey area.
Fold up and glue together the two axles.
Tightly roll up the two drive pins and glue them shut.
Thread the drive wheel sides onto the drive wheel axle lining them up with the two grey lines
Glue the sides of the drive wheel into place so that they are curved.
Expand the cross holes at the ends of the drive wheel with a cocktail stick then thread the drive pins into place.
Fold over and glue together the geneva wheel so that it is double thickness. When the glue is dry, cut out the piece then fit it to the second axle lining it up with the grey line.
Assemble the handle as shown above.
Glue the two halves of the box together at one end only. Thread the geneva wheel and drive wheel into the correct hole using the picture above as guidance. Glue the washer into place.
Glue the box closed then glue the washers into place on the back. Glue the handle to the axle then glue the face to the tabs on the drive wheel.
Done! Turn the handle a full turn and the geneva drive advances two quarter turns flipping the face over. Rack and pinion next.