Limit Snap Gauges

INTRODUCTION

This document describes how to design and manufacturing simple and low cost snap gauges of various sizes and shapes. Manufacturing materials also included.

MAIN SECTION

This is a gauge to inspect whether the diameter of shaft is within a given tolerance, smaller than a specified MML (maximum material limit) or not and larger than the specified LML (least material limit) or not. The user applies the opening of gauge to the shaft. Slowly moves the gauge towards the shaft. If the shaft passes the Go gauging surface at all measuring points at the working load without any difficulty, then the diameter is smaller than the specified MML. If the No Go gauging surface bites the shaft, the gauge shall not pass at all the positions when the working load is applied to the gauge, then diameter is larger than the specified LML.  The inspection shall be carried out at least in two directions perpendicular each other and in the axial direction at positions adequate to the length not less than three.