Precision Twist 4ASMCO 5.7mm Bronze Cobalt Screw Machine Length Drill 135 Degree Split Point 032570

This Precision Twist screw machine length drill bit is a 135-degree split-point, heavy-duty, round shank drill bit made of high-speed steel and cobalt with a bronze (gold) oxide finish. For best use drill with hardened, tempered alloy steel, stainless steel, nodular graphite, malleable cast iron, titanium, nickel and hard material-cemets. It is suitable for drilling to a depth up to two-and-a-half times the diameter of the drill. The shank diameter is the same as the drill size. The series has a type N flute form (a regular helix angle of 21 to 34 degrees). The bronze oxide is a low temperature heat treatment which reduces grinding stress within the tool, and has an appealing, easy-to-identify gold color. Gold oxide is commonly used to identify cobalt steel tools. Spiral flutes act as a passageway for chip extraction from the hole and for coolant to enter the hole. Right-hand twist brings chips up and away from the cutting edge. Made of HSS with cobalt, which is many times harder/stiffer than HSS, will hold an edge longer, and will deflect less than HSS. These are also more resistant to heat than HSS. These qualities allow it to run at higher speeds and feeds.