Jobber Drill Set - Wire Gauge Bright HSS

• 20 Piece Bright HSS Jobber Set No.61 - No.80.
• Bordo Wire Gauge Quicksilver M2 Hss Jobber Drill.

About 118° Split Point (crankshaft point)

• The split point is self-centering and reduces the need for end thrust.
• Friction at the workpiece is reduced. 118° point angles are ideal for use in materials such as mild steel and cast iron.
• The 118° point creates easily controlled chips that are wide and thin.

Usage

• Gauge size drill calculations are generally made utilizing a reference book or table. For example to drill a hole that is 10 thou (a thousandth of an inch = .001) bigger than a 1/8" bolt the user must first work out that 1/8" is 125 thou so the required hole size is 135 thou.
• Using a reference table establishes that you would need a number 29.
• Number drill bit gauge sizes are analogous to but different from American wire gauge.
• Number gauge is most commonly used from size 80 (the smallest) to size 1 (the largest) followed by letter gauge size A (the smallest) to size Z (the largest).
• Number gauge is actually defined down to size 97 but these smallest sizes are very rarely used.

Drill Bit Surface Treatment

• Bright Finish Jobber Drills have no surface treatment and are supplied in the as-ground condition.
• These tools are suitable for general purpose use, particularly for non-ferrous applications.

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