3 Flute vs 4 Flute Thread Mill for HRC65 Steel: How Flute Count Affects Thread Milling Performance
Last month, a precision injection mold client in Stuttgart sent us urgent SEM images of broken cutting edges. They had snapped two imported coated thread mills back-to-back in an M6×1.0 blind hole. The workpiece was a core slide made of Vanadis 4 Extra cold-work powder steel, hardened to 64–65 HRC. The setup tech had switched