Reverse Engineering Spur Gears
GearGen.XYZ was built around the idea of being able create gears from scratch using fixed parameters like center distance, gear cutting tools, and existing gears. It happens that creating a gear that can be cut by a cutting tool makes reverse engineering an easier process. This page is a guide to help you do that.
I will walk you through the process of reverse engineering a spur gear using GearGen.XYZ, but first I want to make an important point about about the configuration sidebar and the importance of each of the cards selected and more specifically what has left out.
Configuration Sidebar Card Summary
1. Add a Gear
The add a gear card allows you to add a gear to the current gearset. The gear is added paired to the gear number before it in the set. Gear 3 and above can have the gear it meshes with edited with the driving gear selection below.
2. Convert pitch system
If you measured in millimeters, convert module to diametral pitch (or vice versa) so your gear math stays consistent.
3. Verify geometry
GearGen.XYZ includes reference lookups intended for verification. Use them to confirm your measured pitch geometry is consistent for mating gears.
4. Iterate and sanity-check
Small measurement errors can shift derived pitch values. Iterate by trying nearby module/DP values and pressure angles, then re-check span and base pitch consistency.
Tip: The How to Use section includes a note about measuring spans when reverse engineering and inspection.