Studies on Quantification of Sensuous Sharpness and Mechanical Sharpness of Wood Cutting Tools. IV. Effects of Cap Iron upon Change of Cutting Phenomena, and Cutting-Force Components is Orthogonal Wood Cutting with Knife equipped with a Cap Iron

In the wood cutting process with a knife equipped with a cap iron, it is important to obtain the optimum conditions of edge angle of the cap iron (βR) and distance between knife edge and cap iron edge (ℓk) and to investigate the changes of cuttinggforce components acting on a knife face and on a cap-iron face and the other cutting phenomena with βR, ℓk and grain angle (φ1) (Figs.1(a) and (b)). In order to obtain quantitative information on them, the basic orthogonal cutting tests, in which the materials used were air-dried wood boards of hinoki (Chamaecyparis obtusa END), were performed using the conventional knife as shown in Figs. 1(c) and (d). The cuttingforce components were measured, and, in addition, several cutting phenomena were observed and estimated. Using thesi results. the effects of βR, ℓk, and φ1 on the cutting-force components and the other cutting phenomena were clarified (Figs. 2～8). The optimum conditions of the cap iron are βR≒55～60° and ℓk≒0.3～0.4mm, under cutting angle of the knife (θk) of 35° and depth of cut (tn) at 0.3mm