The performance of 3d printed dowel with three different surface designs in furniture joints

The shear strengths of the joints produced by using Poly Lactic Acid (PLA), PLA+ Thermoplastic Polyurethane (TPU), and resin (Acrylic Photopolymer) with three different surface design of the dowels including, grooved, straight, and cross were investigated compared, wood and plastic dowels. The Results indicated that among L-type furniture joints, those manufactured from PLA and conventional wood dowels displayed the highest shear resistance, followed by L-type furniture joints with dowels made from PLA+TPU, resin, and plastic. Generally, differences in dowel patterns did not have a statistically significant impact on the shear resistance of L-type joints, except for the straight pattern dowels made of resin, which exhibited a statistically higher shear resistance than the grooved pattern dowels. Regarding the failure mode results, only PLA, PLA+TPU, and wooden dowels showed signs of elongation and crushing within the dowel holes. Conversely, in joints using dowels produced from resin and plastic, the dowels broke under shear stress, without displaying elongation, and did not leave any evidence of crushing in the dowel holes. Overall, the results of the study indicated that dowels made only PLA exhibited similar shear resistance compared to conventional wood dowels. Additionally, the study demonstrated that 3D-printed dowels were stronger than conventional plastic dowels.