SOME FUNDAMENTAL-ASPECTS OF WOOD CHIPPING

To improve chip quality with regard to chip and fiber damage, the mech anisms of chip formation must be better understood. Therefore, an expe rimental setup which can measure the cutting force in two dimensions i n low-speed chipping was developed. The influence of clearance angel, bevel angle and chip length on cutting force, chip thickness:length ra tio, and fracture mode was studied. It was discovered that the force c omponent perpendicular to the movement of the knife could be quite hig h and that the clearance angle had a large effect on the resulting cut ting force. The experiments revealed that chip formation is quite comp licated, since the variables interacted in an unexpected manner. Thus a factorial experimental design is crucial in any study of wood chippi ng, because the response to a change in one variable depends on the va lues of the other variables.