Evaluation and development of methods of improving fasteners and joints performance in wood -base composite case furniture

The objective of this study was to develop and evaluate methods of improving fastener and joint performance in wood-based composite case furniture. In general, several types of joints and fasteners were tested and evaluated. This study, accordingly, provides much of the information needed for the product engineering of case furniture constructed of particleboard and medium density fiberboard. In order to achieve the desired objective and to produce practical results, the boards chosen for the project were representative of the quality of the material usually used in the construction of case furniture. Results of the edge breaking strength tests indicated that breaking strength of the corner joints increased approximately in proportion to the square root of both IB and MOR properties. A clear relationship between edge breaking strength and MOE, MOR, and IB could not be found in either the tension or the compression tests. Edge pull-out test results indicated that edge distance and hole diameter have a significant effect on the edge pull-out strength of the particleboard and medium density fiberboard. Test results for withdrawal strength of screws indicate that both face and edge withdrawal strength of screws were close to what have been obtained in the previous studies done by Eckelman. Using adhesive with screw, withdrawal strength resistance was increased in both MDF and particleboard panels. It is clear that the performance of the joints is not related to the cost of the fasteners. In many cases, joints with low performance were the most expensive. Cap screws, for example, had the highest cost but low performance. On the other hand, sheet metal screws with glue were cheaper but higher in performance