Abstract
There are three methods of grinding a twist drill point in practice, i, e., to grind a normal conical surface, inverted conical one and cylindrical one. The authors have analyzed lip angles, chisel-edge angles, rake angles and clearance angles geometrically based upon the actual grinding process of these points. The object of the present research is to obtain the proper geometrical grinding conditions in order to realize the most suitable angles of the point.
The first report shows the analysis of the point ground to the normal conical surfaces.
