12:1 Reduction Gearbox 

In my Mechanical Engineering Design (MIE243) course, our team of 4 created a parallel gearbox with input and output shafts which are colinear and on opposite sides of the gearbox. The speed ratio is slightly greater than a 12:1 reduction. Images of a 10 tooth and 35 tooth straight spur gear can be seen below, as well as the inner shaft, the input shafts and the housing which were designed with holes to decrease the time for 3D printing. All the design was done using SOLIDWORKs.