Document Type

Undergraduate Project

Date of Degree Completion

Spring 2018

Degree Name

Bachelor of Science


Engineering Technology

Committee Chair

Dr. Craig Johnson

Second Committee Member

Professor Roger Beardsley

Third Committee Member

Professor Charles Pringle


Neil Hauff, a business owner and entrepreneur from the Yakima valley challenged a team of engineering students from Central Washington University to design a motorized apple tree pruner. This report will discuss the engineering and construction that went into creating the housing of the tree pruner. The housing component needed to be able to protect the moving parts of the pruner, while withstanding the rotational torque produced by the Makita power drill used to drive the pruner. The biggest constraint in designing the housing was to keep the weight of the housing component under 1.5 lbs, while still keeping the structural strength to perform during work conditions. The pruner’s effectiveness was tested by checking to see if the pruner housing held everything together when the motor was engaged with full capacity and its cutting blades were stuck in a large branch. The pruner housing held all moving components in place and there were no signs of failure due to the motor housing design. The overall final weight of the motor housing was 0.93 lbs, exceeding the anticipated weight of the pruner housing. While other components of the overall pruner design need improvement in design, the next step to take in improving the pruner housing is to optimize the machinability and ergonomics of the housing.