The Cleveland 1980 jobber length, powdered-metal steel drill bit, with coolant channels, has a fast helix angle, with a 140-degree drill point and Titanium carbonitride (TiCN) surface treatment, for high-performance drilling applications and chip removal. It is most suitable for numerical control (NC) or computer numerical control (CNC) applications where high productivity and accurate holes are needed. The jobber length has length and reach to work with the widest range of materials and applications. The shank diameter is the same as the drill size.
As the coolant flows through the coolant holes, it flushes chips away from the cutting zone and moves them along the drill flutes until they exit the hole. The key factors are coolant volume and pressure. The benefits of providing coolant internally directly to the cutting edge include higher cutting speeds, higher feed rates, longer tool life, less frequent sharpening, and a superior finish. The coolant assists in clearing the chips from the cutting edge and its pressure forces the chips along the lines of the flutes, which allow for drilling greater depths without repeated withdrawal of the drill to clear chips. Higher than normal speeds and feeds are needed to help ensure chips to curl and break, instead of producing long stringy chips. The 1980 series has a faster-than-normal 40-degree helix angle to help ensure efficient chip removal.
While the 1980 series, also known as Q-PM, can be used on most materials, it is most suitable for drilling into medium and low carbon steel, tool steel, cast iron, and stainless steel. TiCN coating lubricates the drill bit for high-temperature stability, and offers increased hardness and greater abrasion resistance than uncoated or TiN-coated tools. Spiral flutes act as a passageway for chip extraction from the hole and for coolant to enter the hole. The right-hand twist brings chips up and away from the cutting edge. Round shanks allow use with a wide variety of tool holding systems. The 140-degree drill bit point angle works well for hard and tough materials. The lip clearance is very shallow (6 to 8 degrees) to provide support for the cutting edges. The short cutting edge helps reduce friction and heat during drilling, which helps extend tool life. Powdered-metal steel offers performance that approaches that of solid carbide tools but with the toughness and shock-resistance of high-speed steel (HSS).
The tolerances for various aspects of the Cleveland drill bits are: drill diameter range through 1/8” +0.0000”/-0.0005”, over 1/8” to 1/4” +0.0000”/-0.0007”, over 1/4” through 1/2” +0.0000”/-0.0010”, over 1/2” to 1” +0.0000”/-0.0012”, over 1” to 2” +0.0000”/-0.0015”, over 2” to 3-1/2” +0.0000”/-0.0020”; drill overall length and flute length #80 through 1/8” +0.1250”/-0.0626”, over 1/8” to 1/2” +0.1250”/-0.1250”, over 1/2” to 1” +0.2500”/-0.1250”, over 1” to 2” +0.2500”/-0.2500”, over 2” to 3-1/2” +0.3750”/-0.3750”; drill point angle diameter range 1/16” to 1/2” included angle 118 or 135 degrees +/-5 degrees, over 1/2” to 1 1/2” included angle 118 degrees +/-3 degrees, over 1-1/2” to 3-1/2” includes angle 118 degrees +/- 2 degrees; drill lip height diameter range 1/16” to 1/8” total indicator variation 0.0020”, over 1/8” to 1/4” total indicator variation 0.0030”, over 1/4” to 1/2” total indicator variation 0.0040”, over 1/2” to 1” total indicator variation 0.0050”, over 1” to 3-1/2” total indicator variation 0.0060”.
Drill bits are cutting tools used to make holes in a range of materials. They are used in machines such as handheld portable drills, drill presses, machining centers, and lathes. Drill bits come in a variety of types and lengths. Twist drill bits are the most common type of drill bit. They are a round, twisted shaft, end-cutting tool with two or more cutting edges and two or more flutes. Jobber drill bits are the most common length of twist bit. They have length and reach to work with the widest range of materials and applications.
Greenfield Industries manufactures tools under the brand names Cleveland, Chicago-Latrobe, Cle-Line, Vermont Tap & Die, Bassett, Putnam Tools, Geometric, Vers-O-Tool, H & G, and Acme-Fette. The company owned by Top-Eastern Group and headquartered in Seneca, SC, makes tools that meet American National Standards Institute (ANSI), National Aerospace Standard (NAS), and Deutsches Institut für Normung (DIN) standards.