Spotting Drills/Centering Drills for Pre-Drilling Holes
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These NC Spotting Drills have short flutes and no land or body relief to maintain maximum rigidity. For use on numerous materials including aluminum, brass, plastic, wood as well as more difficult materials such as steel, stainless steel, composites, inconel, and titanium. When tight tolerance hole locations are required, spot drilling is required to prevent the drill from walking. Spotting drills improve the accuracy of the secondary drilled hole. May also be used for chamfering or deburring. Each size may be used on a wide range of hole diameters. The typical diameter of a spot drilled hole is 50-75% of the secondary final drill diameter. For softer materials, 90° points are typically used to start drills up to 120°. 120° points are used to start drills above 120° (typically 135° drills). This allows the outer cutting edge of the secondary drill to start cutting before the point touches. For tougher and harder materials and for high performance secondary drills, the 145° point is recommended. This allows the point of the secondary drill to touch before the outer cutting edge. This helps to reduce chatter and prevent chipping of the secondary drill’s cutting edges. |
Our standard sizes are shown in the below tables. You can order below or contact us. We keep many sizes of our tools in stock - ready to ship. |
Spotting Drills - Two Flutes (SD)Standard Sizes - order below |
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| Overall Shank Diameter (inches) |
Overall Length (inches) |
Included Angles |
| .125 (1/8) | 2.0 & 4.5 | 90° 120° 145° |
| .1719 (11/64) | 6.5 | |
| .1875 (3/16) | 2.0 | |
| .250 (1/4) | 2.0 & 6.5 | |
| .375 (3/8) | 3.0 | |
| .500 (1/2) | 3.0 | |
| .562 (9/16) | 3.0 | |
| .750 (3/4) | 3.0 | |
Metric Sizes - order below |
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| 4 mm (.157") | 50 mm (1.97") | 90° 120° 145° |
| 6 mm (.236") | 50 mm (1.97") | |
Contact us for sizes not shown here or send us a custom tool request.
Our custom tools have a very quick turn around.
Our custom tools have a very quick turn around.
Spotting Drills - Two Flutes (SDmet)
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| Overall Shank Diameter (mm) | Overall Length (mm) |
Complete Your Part # by selecting options from drop down boxes below part # example: SDmet-4x50-.90 |
Price (each) |
| 4 mm (.157") |
50 mm (1.97") |
$13.97 | |
| 6 mm (.236") |
50 mm (1.97") |
$14.97 | |
End Mills, Cutting Tools, Chamfering Tools, Broken Tap Removal Tools