DESIGNATION SYSTEM SOLID CARBIDE MILLING CUTTERS X X A XXX 1 2 3 4 1 2 3 4 TOOL TYPE DENSITY STYLE TOOL DIAMETER 4 Solid carbide end mills & 5 Solid carbide, 1 & 2 no. of A High speed cutter 3-digit number screw on flutes, large spacing e.g. diameter .250" = 25 B Ball nose cutter – 6 Solid carbide, cylindrical 3 no. of flutes, normal spacing C 90° cutting angle with chamfer on cutting edge 7 Solid carbide, 4 & 5 no. of flutes, narrow spacing D 90° cutting angle with radius on cutting edge 8 Solid carbide, 6 - 9 no. of flutes, extra narrow spacing J 90° cutting angle with sharp cutting edge Y Thread mill A = Letter X = Number E = Number or letter H = Letter 0 = Standard or special design * = Depending on tool type up to 4 digits can be used on this position when detailed designation is required. 450