Cleveland 2213 Cobalt Steel Drill Bits - 12 Pack, #1 Wire Size, 135° Split Point, Gold Oxide Finish for High-Speed Drilling | Perfect for Metalworking, Woodworking, and DIY Projects

The Cleveland 2213 Cobalt heavy-duty jobber length, high-speed steel (HSS) containing cobalt drill bit has a 30-degree helix angle, with a 135-degree split-point and straw oxide surface treatment, which is designed for heavy-duty drilling applications. Conforms to NAS 907 type J specifications. The shank diameter is the same as the drill size. This drill has high red hardness for extended wear life in high heat conditions. The 2213 series performs best when drilling into aluminum, copper alloys, Inconel, titanium alloys, tool steel, die steel, structural steel, and precipitation-hardness stainless steel. Straw oxide is a low-temperature heat treatment that reduces grinding stress within the tool. Spiral flutes act as a passageway for chip extraction from the hole and for coolant to enter the hole. The twist of the flutes brings chips up and away from the cutting edge. 135-degree drill point reduces walking when starting a hole and penetrates more easily than a convention point. Round shanks allow use with a wide variety of tool holding systems. > While the 2213 series was designed for the aircraft industry, it works well for other drilling applications. Made of cobalt-powder-metal substrate which is many times harder and 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. They are made to ANSI and DIN industry standards, which help ensure that drill bits around the world, conform to the same specifications. The tolerances for various aspects of the Cleveland drill bits are: drill diameter range (inches) through 1/8 +0.0000/-0.0005, over 1/8 through 1/4 +0.0000/-0.0007, over 1/4 through 1/2 +0.0000/-0.0010, over 1/2 through 1 +0.0000/-0.0012, over 1 through 2 +0.0000/-0.0015, over 2 through 3 1/2 +0.0000/-0.0020; drill overall length and flute length #80 through 1/8 +0.1250/-0.0626, over 1/8 through 1/2 +0.1250/-0.1250, over 1/2 through 1 +0.2500/-0.1250, over 1 through 2 +0.2500/-0.2500, over 2 through 3 1/2 +0.3750/-0.3750; drill point angle diameter range (inches) 1/16 through 1/2 included angle (degrees) 118 or 135 +/-5 degrees, over 1/2 through 1 1/2 included angle (degrees) 118 +/-3 degrees, over 1 1/2 through 3 1/2 includes angle (degrees) 118 +/- 2 degrees; drill lip height diameter range (inches) 1/16 through 1/8 total indicator variation (inches) 0.0020, over 1/8 through 1/4 total indicator variation (inches) 0.0030, over 1/4 through 1/2 total indicator variation (inches) 0.0040, over 1/2 through 1 total indicator variation (inches) 0.0050, over 1 through 3 1/2 total indicator variation (inches) 0.0060. Drilling, or hole making, is the most common metalworking operation in the world. Twist drill bits are the most common type of drill bit used. Twist drill bits can be used in hand-operated drills, standalone drill presses, or a lathe. Greenfield Industries, which are a part of Top-Eastern Group, is one of the largest manufacturers of twist drills. They also manufacture cutting tools and related products under the following brands: Cleveland, Chicago-Latrobe, Cle-Line, Vermont Tap & Die, Bassett, Putnam Tools, Geo Met RJC, H & G, Vers-O-Tool, and Acme-Fette. The company has locations around the world, and provides tools adhering to ANSI, NAS, and DIN standards.