The crank slider mechanism is the basis of the models including the Reindeer Ride model. As the crank (yellow) turns the pushrod and slider is moved up and down, the end point tracing out a curved, but not necessarily circular motion.
By altering the various dimensions, different motions can obtained, the key distances are
    * Diameter of crank
    * Crank centre to slider fixed point (green)
The ratio of these distances changes the locus of the end of the pushrod.
Members can download and make an adjustable crank slider model showing in a hands on way how the crank slider works and how changing the geometry of the crank slider changes the movement of the push rod.
Find out more here.
Make you own simple clank slider model. This kit is intended as a starting point for your own designs. Download it for free here.