American Made
Drill Bits


Ultra Bor Super Premium Drill Bits: The Ultra Bor drill bit has a thinner web and will substantially outperform cobalt drills in work hardening stainless steel applications.  Ultra Bor drills are made of special hi-moly tool steel, which is much tougher than cobalt steel.  The web on an Ultra Bor drill can be thinned considerably due to the toughness of the steel.  Because of the thinner web, an Ultra Bor drill will penetrate stainless fast enough to continually cut beneath the chip which is hardening from deformation.  This means the drill is cutting softer steel.

Hi-Moly Tool Steel is heat treated at 2185 degrees and then nitro-carburize finished at 950 degrees to be measurably harder than high-speed steel.  Space age nitro-carburized steel withstands substantially higher drilling temperatures while maintaining sharpness. (source:

Speeds and Feeds:  Cutting speed (also called surface speed or simply speed) is the speed difference between the cutting tool and the surface of the workpiece it is operating on. It is expressed in units of distance along the workpiece surface per time, typically surface feet per minute (sfm) or meters per minute (m/min).  Feed rate is the relative velocity at which the cutter is advanced along the workpiece; its vector is perpendicular to the vector of cutting speed.  For more information check out our Speeds and Feeds page.

Split Point:  Reduces thrust and eliminates walking at the drill point. Ideal for tight tolerance and portable drilling. Self centering.

Jobber Length:  Industrial standard for drill bit length.  We recommend going with the Ultra Bor Super Premium

Mechanic’s Length:  Shorter than jobber length drill bits with better rigidity and increased strength.

Screw Machine Length:  Shorter flute and overall length for maximum rigidity and accuracy. Designed to reduce deflection and breakage.

Taper Length:  Longer than jobber length drill bits where a deeper hole is required.

Extra Length:  Longest overall length for drilling deep and hard-to-reach areas.

Tap & Dies:  Cutting tools used to create new screw threads, which is called threading.  A tap is used to cut the female portion of the mating pair.  A die is used to cut the male portion of the mating pair.  The process of cutting threads using a tap is called tapping, whereas the process using a die is called threading.  Both tools can be used to clean up a thread, which is called chasing.  If you are having issues please check out our Tap Troubleshooting page.

Slow Spiral Drill Bit:  A drill with elongated flutes. Also called low helix angle drills, slow-spiral drills have high rigidity and withstand great force.  Used in masonry drilling operations.

Reduced Shank:  Allows drill bit diameter to exceed the chuck diameter.

Countersink:  A boring bit having a conical-shaped cutter; used to make a depression to allow the bolt or screw to lay flush with the surface

Carbide:  Designed for high speed cutting of difficult-to-machine materials such as cast iron, nonferrous metals, and abrasive materials.

Black Oxide, Steam Oxide, and Black and Gold Finish:  Helps retain lubricants for improved chip flow and better wear life. Recommended for iron and steel. Should not be used with nonferrous metals such as aluminum.

Unified National Fine (UNF):  V-Thread standard for fine thread.  They simply refer to the size of the threads relative to the screw diameter (screw thread pitch).  Fine threads can be made inaccurately.

Unified National Course (UNC):  V-Thread standard for course thread.  They simply refer to the size of the threads relative to the screw diameter (screw thread pitch).  Coarse threads can be made accurately.

Burrout Brad Point Bit:  These high performance drills made from Hi-Moly tool steel will cut holes in wood or plastics and leave no burr. They will also drill splinter free holes in wood. The special BURROUT™ point cuts at the circumference of the hole to avoid the break through burr problems common with standard point drills. When drilling into higher tensile strength metals such as cold rolled steel; a small pilot hole may prove helpful since the center spur does not cut aggressively.  Also know as a lip and spur drill bit.

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