When it comes to power transmission in DYI project sprocket gears, sometimes called chain gears, offer several advantages over other types of methods of power transmission such as belts/pulleys and meshing gears.
1. Unlike belts they can transmits large amounts of torque 2. Unlike meshing gears they don't need to be constantly lubricated 3. Unlike belts and mesh-gears the spacing between centers can be easily adjusted by shortening/lengthening the chain
Despite these advantages, few people know how to draw sprocket gears, which are designed based on pitch rather than mesh.