The Cleveland C70370 screw machine length drill bit set contains 15 uncoated (bright) high-speed steel drill bits in inch sizes 1/16" to 1/2" in 1/32" increments. A self-centering 135-degree split point penetrates hard material without a pilot hole and produces smaller chips that reduce clogging compared to a 118-degree point. High-speed steel (HSS) provides hardness for wear resistance, and the uncoated finish has no additional surface treatment or coating. The round shank accommodates most drill chucks. The set comes in a metal index case with labeled compartments for identification and organization. Drill bits meet American National Standards Institute (ANSI) and National Aerospace Standard (NAS) 907 specifications.
Drill bits are cutting tools used to make holes in a range of materials using machines such as handheld portable drills, machining centers, and lathes. Drill bits come in a variety of lengths and types, the most common of which is the twist drill bit. The round, twisted shaft of the twist drill bit typically has two cutting edges and flutes. The helical twist of the flutes brings chips up and away from the cutting edges and allows for coolant to reach the cutting edges. Jobber length twist drill bits, the most common length of twist drill bit, offer a good compromise of length and reach to work with the widest range of materials and applications. Mechanics length twist drill bits (also called maintenance length) are a little shorter than jobber length and less prone to deflection when drilling. Short length twist drill bits (also called stub or screw-machine length) are the shortest and stiffest twist drill bits, helping to reduce the chance of deflection or breakage when drilling. Reduced shank drill bits (also called Silver and Deming drill bits) have a shank that is smaller in diameter than its shaft, permitting drilling machines with either a 1/2" or 3/4" drill chuck to create large holes. Long length twist drill bits (also called taper length) are a little longer than jobber length, allowing for deeper holes and longer reach. Extra long twist drill bits (also called extension) are longer than long length twist drill bits for greater reach or for drilling deeper holes.
Cleveland manufactures tools for drilling, threading, and milling applications. The company, headquartered in Seneca, SC, meets International Organization for Standardization (ISO) standard 9001.