Manufacturing feasibility analysis and load carrying capacity of computer numerical control cut joints with interlocking assembly feature

Abstract

The basic manufacturing feasibility and load carrying capacity of computer numerical control (CNC) were evaluated for router-cut joints. More precise and complex shaped geometry was cut on a CNC machine so that joint strength increased via providing a better self-locking system. Using the design for manufacture and assembly (DFMA) analysis, the raw material type and joint design were determined as the main drivers that have direct influence on the processing time and yield of the manufacturing process. Moreover, the bending moment capacity of the joints was determined in compression and tension testing and benchmarked those of rectangular mortise and tenon (RM&T) and dowel joints. The results showed that joints constructed of plywood performed better than those of medium-density fiberboard according to DFMA compliance score values. Moreover, the load capacity level of joints constructed of plywood provided stronger joints than MDF. In compression tests, CNC router-cut joints constructed of both plywood and MDF reached equal or higher strength relative to traditional joints. Furthermore, in tension tests, those of strength were lower compared to compression test results. The outcome of this study will contribute to the theoretical and practical knowledge of furniture joinery design.