Metrology of the geometric characteristics of mortise and tenon joints through Geometrical product specification (GPS) standards

Abstract

The mutual interaction of the contact surfaces of the mortise and tenon joints is complex. The geometry of the joint affects the tribology of these surfaces. The optimal shape of mortise and tenon joints is also represented by their geometric features. The Geometrical Product Specification System (GPS) is a set of guidelines, concepts, and symbols that establish the geometry of a part's allowable tolerances to guarantee its functionality. This review paper presents an investigation of the possibilities for metrology of the geometrical characteristics of mortise and tenon joints and their expression and representation through Geometrical Product Specification (GPS) standards. For this purpose, the metrology of the most commonly used joint in wood chair construction is presented. The following types of tolerances are presented: dimension tolerances (length, width and thickness); form tolerances (straightness and flatness); orientation tolerances (parallelism and perpendicularity) and location tolerances (symmetry). Metrology and presentation of the geometric characteristics of mortise and tenon joints through GPS standards is a useful method that satisfies functional requirements and quality control during processing. The phases and operations of measuring the geometric characteristics of the joints using manual instruments are presented.