We ascertained the strength properties of a commercial dovetailjoint. Shearing tests were performed for four section sizes of a commercially available dovetailjoint to ascertain its strength properties. To additionally establish the effect of differences in tree species, the tests were conducted for three species.The optimum dimension of the shape that needs improvement was calculated by the shear yield strength estimation formula. As a result, shear yield strength is improved when koshisei of commercial dovetailjoint with cross section size 105 mm×180mm is increased by 15mm.
