spur gear training tool

thingiverse

This set of spur gears serves as a hands-on tool for grasping fundamental spur gear theory concepts. Large teeth are intentionally designed to facilitate easier observation of tooth interaction and precise tracking of each engagement. Two thread holes provide clear visual demonstrations that gear tooth interactions consistently follow the 20-degree pressure angle established at the intersection of the pitch diameters. Critical gear parameters are as follows (in inches): Diametral Pitch = 3 inch Number of Gear Teeth = 12 Pressure Angle (phi) = 20 degrees Utilizing standard spur gear equations, these values yield: Pitch Diameter (PD) = 4 inch Outer Diameter (OD) = 4.666... inch Please note that although units above are provided in inches, the accompanying STL files contain measurements in millimeters. For supplementary knowledge on gears and gear design, consult the following references: Boston Gear's comprehensive guide to spur and other gear theories: http://www.bostongear.com/pdf/gear_theory.pdf Additional insights into spur and spiral gear processes can be found in "Parametric Design of a Spiral Gear Process," an extensive report by Worcester Polytechnic Institute's Jeffery Baker, Jason Reynolds, and Stephen Tecce: https://www.wpi.edu/Pubs/E-project/Available/E-project-042811-130543/unrestricted/Final_Report-Parametric_Design_of_a_Spiral_Gear_Process.pdf To assemble the gear training set, perform the following steps: Print two of each part (gear_4_DP3_N18_150116a.stl and gear_4_DP3_N18_150117_link.stl). When joining parts together, use caution to avoid locking gears due to uneven meshing. Visual aids are available via online resources for assembly guidelines. Gently place glue on top of the post and within the socket hole to achieve secure connections. Follow pictures demonstrating gear placement to guarantee proper tooth interaction and accurate pressure angle demonstrations. For educational purposes, a strand is recommended for insertion as illustrated in provided assembly pictures, facilitating clear visual display of each line of engagement between gears.