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Holemaking Products - Counterbores & Porting Tools For Sale | A1 Tooling - (1669 Products)

Made in USA - 4 Flutes, 5/8" Diam, 1/4" Pilot Hole Diam, Solid Carbide Reverse Counterbore - A1 Tooling

Made in USA - 4 Flutes, 5/8" Diam, 1/4" Pilot Hole Diam, Solid Carbide Reverse Counterbore


Item #: 09938077
Brand: Made in USA
Model #:

Features and Benefits

Solid carbide provides better rigidity than high speed steel. It is extremely heat resistant and used for high speed applications on cast iron, nonferrous materials, plastics and other tough-to-machine materials.
Product Specifications
Counterbore Diameter (Inch) 5/8
Pilot Hole Diameter (Inch) 1/4
Counterbore Material Solid Carbide
Standard Pilot Model Number Compatibility 185-5
Oversize Pilot Model Number Compatibility 186-8
Number of Flutes 4
Overall Length (Inch) 5/8
Corner Radius (Inch) 1/64
Aircraft-Style No

$160.04

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Made in USA - 4 Flutes, 1/4" Diam, 3/32" Pilot Hole Diam, High Speed Steel Reverse Counterbore - A1 Tooling

Made in USA - 4 Flutes, 1/4" Diam, 3/32" Pilot Hole Diam, High Speed Steel Reverse Counterbore


Item #: 09937137
Brand: Made in USA
Model #:

Features and Benefits

High speed steel (HSS) provides good wear resistance and can be used in general purpose applications on both ferrous and nonferrous materials.
Product Specifications
Counterbore Diameter (Inch) 1/4
Pilot Hole Diameter (Inch) 3/32
Counterbore Material High Speed Steel
Standard Pilot Model Number Compatibility 185-1
Oversize Pilot Model Number Compatibility 186-1
Number of Flutes 4
Overall Length (Inch) 1/2
Corner Radius (Inch) 1/32
Aircraft-Style No

$30.67

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Made in USA - 4 Flutes, 5/16" Diam, 1/8" Pilot Hole Diam, High Speed Steel Reverse Counterbore - A1 Tooling

Made in USA - 4 Flutes, 5/16" Diam, 1/8" Pilot Hole Diam, High Speed Steel Reverse Counterbore


Item #: 09937160
Brand: Made in USA
Model #:

Features and Benefits

High speed steel (HSS) provides good wear resistance and can be used in general purpose applications on both ferrous and nonferrous materials.
Product Specifications
Counterbore Diameter (Inch) 5/16
Pilot Hole Diameter (Inch) 1/8
Counterbore Material High Speed Steel
Standard Pilot Model Number Compatibility 185-2
Oversize Pilot Model Number Compatibility 186-2
Number of Flutes 4
Overall Length (Inch) 1/2
Corner Radius (Inch) 1/32
Aircraft-Style No

$32.29

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Made in USA - 4 Flutes, 5/8" Diam, 1/4" Pilot Hole Diam, High Speed Steel Reverse Counterbore - A1 Tooling

Made in USA - 4 Flutes, 5/8" Diam, 1/4" Pilot Hole Diam, High Speed Steel Reverse Counterbore


Item #: 09937319
Brand: Made in USA
Model #:

Features and Benefits

High speed steel (HSS) provides good wear resistance and can be used in general purpose applications on both ferrous and nonferrous materials.
Product Specifications
Counterbore Diameter (Inch) 5/8
Pilot Hole Diameter (Inch) 1/4
Counterbore Material High Speed Steel
Standard Pilot Model Number Compatibility 185-5
Oversize Pilot Model Number Compatibility 186-8
Number of Flutes 4
Overall Length (Inch) 5/8
Corner Radius (Inch) 1/32
Aircraft-Style No

$39.26

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Made in USA - 4 Flutes, 1/2" Diam, 3/16" Pilot Hole Diam, Solid Carbide Reverse Counterbore - A1 Tooling

Made in USA - 4 Flutes, 1/2" Diam, 3/16" Pilot Hole Diam, Solid Carbide Reverse Counterbore


Item #: 09938010
Brand: Made in USA
Model #:

Features and Benefits

Solid carbide provides better rigidity than high speed steel. It is extremely heat resistant and used for high speed applications on cast iron, nonferrous materials, plastics and other tough-to-machine materials.
Product Specifications
Counterbore Diameter (Inch) 1/2
Pilot Hole Diameter (Inch) 3/16
Counterbore Material Solid Carbide
Standard Pilot Model Number Compatibility 185-4
Oversize Pilot Model Number Compatibility 186-4
Number of Flutes 4
Overall Length (Inch) 1/2
Corner Radius (Inch) 1/64
Aircraft-Style No

$145.48

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Made in USA - 4 Flutes, 3/8" Diam, 3/16" Pilot Hole Diam, High Speed Steel Reverse Counterbore - A1 Tooling

Made in USA - 4 Flutes, 3/8" Diam, 3/16" Pilot Hole Diam, High Speed Steel Reverse Counterbore


Item #: 09937202
Brand: Made in USA
Model #:

Features and Benefits

High speed steel (HSS) provides good wear resistance and can be used in general purpose applications on both ferrous and nonferrous materials.
Product Specifications
Counterbore Diameter (Inch) 3/8
Pilot Hole Diameter (Inch) 3/16
Counterbore Material High Speed Steel
Standard Pilot Model Number Compatibility 185-4
Oversize Pilot Model Number Compatibility 186-4
Number of Flutes 4
Overall Length (Inch) 1/2
Corner Radius (Inch) 1/32
Aircraft-Style No

$33.32

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Made in USA - 4 Flutes, 11/16" Diam, 1/4" Pilot Hole Diam, Solid Carbide Reverse Counterbore - A1 Tooling

Made in USA - 4 Flutes, 11/16" Diam, 1/4" Pilot Hole Diam, Solid Carbide Reverse Counterbore


Item #: 09938101
Brand: Made in USA
Model #:

Features and Benefits

Solid carbide provides better rigidity than high speed steel. It is extremely heat resistant and used for high speed applications on cast iron, nonferrous materials, plastics and other tough-to-machine materials.
Product Specifications
Counterbore Diameter (Inch) 11/16
Pilot Hole Diameter (Inch) 1/4
Counterbore Material Solid Carbide
Standard Pilot Model Number Compatibility 185-5
Oversize Pilot Model Number Compatibility 186-8
Number of Flutes 4
Overall Length (Inch) 5/8
Corner Radius (Inch) 1/64
Aircraft-Style No

$177.77

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Made in USA - 4 Flutes, 1-5/8" Diam, 3/4" Pilot Hole Diam, High Speed Steel Reverse Counterbore - A1 Tooling

Made in USA - 4 Flutes, 1-5/8" Diam, 3/4" Pilot Hole Diam, High Speed Steel Reverse Counterbore


Item #: 09937517
Brand: Made in USA
Model #:

Features and Benefits

High speed steel (HSS) provides good wear resistance and can be used in general purpose applications on both ferrous and nonferrous materials.
Product Specifications
Counterbore Diameter (Inch) 1-5/8
Pilot Hole Diameter (Inch) 3/4
Counterbore Material High Speed Steel
Standard Pilot Model Number Compatibility 185-10
Oversize Pilot Model Number Compatibility 186-22; 186-23; 186-24
Number of Flutes 4
Overall Length (Inch) 1
Corner Radius (Inch) 1/32
Aircraft-Style No

$187.74

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Cleveland - #10 Wire Socket Head Cap Screw Compatible, High Speed Steel, Solid Pilot Counterbore - A1 Tooling

Cleveland - #10 Wire Socket Head Cap Screw Compatible, High Speed Steel, Solid Pilot Counterbore


Item #: 81852121
Brand: Cleveland
Model #: C91700

Features and Benefits

High speed steel (HSS) provides good wear resistance and can be used in general purpose applications on both ferrous and nonferrous materials.
Bright provides a smooth, polished finish on the tool. It increases chip flow in softer materials such as aluminum, wood and plastic.
Product Specifications
Fastener Type Compatibility Socket-Head Cap Screw
Counterbore Diameter (Decimal Inch) 0.3280
Fastener Size Compatibility (Wire) #10
Counterbore Material High Speed Steel
Finish/Coating Bright
Standard or Oversize Pilot Standard
Shank Diameter (Inch) 5/16
Number of Flutes 3
Aircraft-Style No
Pilot Diameter (Decimal Inch) 0.2040
Shank Type Straight
Overall Length (mm) 88.90
Overall Length (Inch) 3-1/2
Overall Length (Decimal Inch) 3.50
Cutting Direction Forward
Material Application Alloy Tool Steel; Carbon Steel; Cast Iron

$112.83

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Interstate - 7/16" Compatible Cobalt, Solid Pilot Counterbore - A1 Tooling

Interstate - 7/16" Compatible Cobalt, Solid Pilot Counterbore


Item #: 45403367
Brand: Interstate
Model #:

Features and Benefits

Cobalt is harder than high speed steel and provides better wear resistance. It is commonly used on high tensile alloys.
Bright provides a smooth, polished finish on the tool. It increases chip flow in softer materials such as aluminum, wood and plastic.
Product Specifications
Counterbore Diameter (Inch) 1/2
Fastener Size Compatibility (Inch) 7/16
Counterbore Material Cobalt
Finish/Coating Bright
Shank Diameter (Inch) 11/16
Pilot Diameter (Inch) 15/32
Shank Type Straight
Cutting Direction Forward

$63.06

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Alvord Polk - 3mm Socket Head Cap Screw Compatible, High Speed Steel, Solid Pilot Counterbore - A1 Tooling

Alvord Polk - 3mm Socket Head Cap Screw Compatible, High Speed Steel, Solid Pilot Counterbore


Item #: 43981471
Brand: Alvord Polk
Model #: 03080

Features and Benefits

High speed steel (HSS) provides good wear resistance and can be used in general purpose applications on both ferrous and nonferrous materials.
Bright provides a smooth, polished finish on the tool. It increases chip flow in softer materials such as aluminum, wood and plastic.
Product Specifications
Fastener Type Compatibility Socket-Head Cap Screw
Counterbore Diameter (Decimal Inch) 0.2362
Fastener Size Compatibility (mm) 3.00
Fastener Size Compatibility (Decimal Inch) 0.1181
Counterbore Material High Speed Steel
Finish/Coating Bright
Standard or Oversize Pilot Standard
Shank Diameter (Decimal Inch) 0.1875
Aircraft-Style No
Pilot Diameter (Decimal Inch) 0.1378
Shank Type Straight
Overall Length (Inch) 4-1/2
Overall Length (Decimal Inch) 4.50
Cutting Direction Forward

$31.93

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Made in USA - #8 Wire Socket Head Cap Screw Compatible, High Speed Steel, Solid Pilot Counterbore - A1 Tooling

Made in USA - #8 Wire Socket Head Cap Screw Compatible, High Speed Steel, Solid Pilot Counterbore


Item #: 08272734
Brand: Made in USA
Model #:

Features and Benefits

High speed steel (HSS) provides good wear resistance and can be used in general purpose applications on both ferrous and nonferrous materials.
Bright provides a smooth, polished finish on the tool. It increases chip flow in softer materials such as aluminum, wood and plastic.
Product Specifications
Fastener Type Compatibility Socket-Head Cap Screw
Counterbore Diameter (Decimal Inch) 0.2720
Fastener Size Compatibility (Wire) #8
Counterbore Material High Speed Steel
Finish/Coating Bright
Standard or Oversize Pilot Standard
Shank Diameter (Inch) 1/4
Number of Flutes 4
Aircraft-Style No
Pilot Diameter (Decimal Inch) 0.1640
Shank Type Straight
Overall Length (Inch) 5
Cutting Direction Forward

$45.17

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Value Collection - 7/32" Head Diam, 5/32" Shank Diam, Counterbore Pilot - A1 Tooling

Value Collection - 7/32" Head Diam, 5/32" Shank Diam, Counterbore Pilot


Item #: 08903148
Brand: Value Collection
Model #:

Product Specifications
Head Diameter (Inch) 7/32
Shank Diameter (Inch) 5/32
Pilot Material Carbon Steel

$9.89

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Keo - 12mm Socket Head Cap Screw Compatible, Cobalt, Solid Pilot Counterbore - A1 Tooling

Keo - 12mm Socket Head Cap Screw Compatible, Cobalt, Solid Pilot Counterbore


Item #: 44850683
Brand: Keo
Model #: 56221

Features and Benefits

Cobalt is harder than high speed steel and provides better wear resistance. It is commonly used on high tensile alloys.
Bright provides a smooth, polished finish on the tool. It increases chip flow in softer materials such as aluminum, wood and plastic.
Product Specifications
Fastener Type Compatibility Socket-Head Cap Screw
Counterbore Diameter (mm) 20.00
Fastener Size Compatibility (mm) 12.00
Counterbore Material Cobalt
Finish/Coating Bright
Standard or Oversize Pilot Standard
Shank Diameter (mm) 12.50
Number of Flutes 3
Pilot Diameter (mm) 10.20
Overall Length (mm) 100.00

$89.46

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Keo - #4 Wire Socket Head Cap Screw Compatible, Cobalt, Solid Pilot Counterbore - A1 Tooling

Keo - #4 Wire Socket Head Cap Screw Compatible, Cobalt, Solid Pilot Counterbore


Item #: 02828390
Brand: Keo
Model #: 55202

Features and Benefits

Cobalt is harder than high speed steel and provides better wear resistance. It is commonly used on high tensile alloys.
Bright provides a smooth, polished finish on the tool. It increases chip flow in softer materials such as aluminum, wood and plastic.
Product Specifications
Fastener Type Compatibility Socket-Head Cap Screw
Counterbore Diameter (Decimal Inch) 0.2170
Fastener Size Compatibility (Wire) #4
Counterbore Material Cobalt
Finish/Coating Bright
Standard or Oversize Pilot Oversize
Shank Diameter (Inch) 5/32
Number of Flutes 3
Aircraft-Style No
Pilot Diameter (Decimal Inch) 0.1430
Shank Type Straight
Overall Length (Inch) 3
Cutting Direction Forward

$47.16

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Union Butterfield - 1/2" Head Diam, 3/8" Shank Diam, Counterbore Pilot - A1 Tooling

Union Butterfield - 1/2" Head Diam, 3/8" Shank Diam, Counterbore Pilot


Item #: 65707424
Brand: Union Butterfield
Model #: 3210156

Product Specifications
Head Diameter (Inch) 1/2
Shank Diameter (Inch) 3/8
Finish/Coating Bright
Aircraft-Style No
Pilot Material High Speed Steel

$55.72

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Union Butterfield - 9/16" Head Diam, 7/16" Shank Diam, Counterbore Pilot - A1 Tooling

Union Butterfield - 9/16" Head Diam, 7/16" Shank Diam, Counterbore Pilot


Item #: 65706780
Brand: Union Butterfield
Model #: 3210173

Product Specifications
Head Diameter (Inch) 9/16
Shank Diameter (Inch) 7/16
Finish/Coating Bright
Aircraft-Style No
Pilot Material High Speed Steel

$72.76

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Value Collection - 1-1/4" Head Diam, 1/2" Shank Diam, Counterbore Pilot - A1 Tooling

Value Collection - 1-1/4" Head Diam, 1/2" Shank Diam, Counterbore Pilot


Item #: 08909749
Brand: Value Collection
Model #:

Product Specifications
Head Diameter (Inch) 1-1/4
Shank Diameter (Inch) 1/2
Pilot Material Carbon Steel

$37.92

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Value Collection - 3/8" Compatible High Speed Steel, Solid Pilot Counterbore - A1 Tooling

Value Collection - 3/8" Compatible High Speed Steel, Solid Pilot Counterbore


Item #: 08861247
Brand: Value Collection
Model #:

Features and Benefits

High speed steel (HSS) provides good wear resistance and can be used in general purpose applications on both ferrous and nonferrous materials.
Product Specifications
Counterbore Diameter (Inch) 19/32
Fastener Size Compatibility (Inch) 3/8
Counterbore Material High Speed Steel
Standard or Oversize Pilot Standard
Number of Flutes 3
Aircraft-Style No
Pilot Diameter (Inch) 13/32
Shank Type Morse Taper
Shank Taper Designation 2MT
Cutting Direction Forward

$63.81

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Keo - #8 Wire Socket Head Cap Screw Compatible, Cobalt, Solid Pilot Counterbore - A1 Tooling

Keo - #8 Wire Socket Head Cap Screw Compatible, Cobalt, Solid Pilot Counterbore


Item #: 02828465
Brand: Keo
Model #: 55209

Features and Benefits

Cobalt is harder than high speed steel and provides better wear resistance. It is commonly used on high tensile alloys.
Bright provides a smooth, polished finish on the tool. It increases chip flow in softer materials such as aluminum, wood and plastic.
Product Specifications
Fastener Type Compatibility Socket-Head Cap Screw
Counterbore Diameter (Decimal Inch) 0.2720
Fastener Size Compatibility (Wire) #8
Counterbore Material Cobalt
Finish/Coating Bright
Standard or Oversize Pilot Standard
Shank Diameter (Inch) 1/4
Number of Flutes 3
Aircraft-Style No
Pilot Diameter (Decimal Inch) 0.1640
Shank Type Straight
Overall Length (Inch) 3
Cutting Direction Forward

$56.91

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