Parking brake for railway cart
The brown weight causes braking forces applied to the rail. Thanks to a small gap in cylindrical joint between the weight and green chassis both pink brake bars can contact the rail at the same time.
Red spring ensures no contact between the brake bars and the rail when unbraking.
The weight, yellow conrod and blue lever create a slider crank mechanism.
STEP files of this video:
http://www.mediafire.com/file/0xdt5xa...