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    43 Products
    About Countersinks
    industrial info icon

    Choose the right countersink angle, body diameter, and number of flutes for your application.

    Long-Reach Extensions for Threaded-Shank Countersinks

    Image of Product. Front orientation. Countersink Extensions. Long-Reach Extensions for Threaded-Shank Countersinks.
    Increase the reach of long-reach threaded-shank countersinks (sold separately). These extensions are compatible with 82°, 90°, and 100° angle threaded-shank countersinks.
    Overall
    Lg.
    Body
    Dia.
    For Shaft
    Thread Size
    Shank
    Dia.
    For Use On
    Each
    Uncoated Carbon Steel
    4"3/8"1/4"-28
    		1/4"Aluminum, Brass, Bronze, Iron, Plastic, Stainless Steel, Steel3109A71000000
    6"3/8"1/4"-28
    		1/4"Aluminum, Brass, Bronze, Iron, Plastic, Stainless Steel, Steel3109A7200000
    12"3/8"1/4"-28
    		1/4"Aluminum, Brass, Bronze, Iron, Plastic, Stainless Steel, Steel3109A7300000
     

    Drill-Bit Countersinks for Wood and Plastic

    These countersinks attach at various points along the drill bit, so one tool will drill countersunk holes for screws of different lengths. They're designed to cut a smooth and even finish in wood and plastic on the first pass.
    Carbon Steel
    Image of Product. Front orientation. Countersinks. Straight Flute, Drill-Bit Countersink, For Cutting Screw Holes, For Wood, Sold Individually, 1 Countersinking End, 4 Flutes.

    4 Flutes

    Stronger than high-speed steel, so it will cut through harder materials. However, high-speed steel is more precise, lasts longer, and cuts at higher speeds.
    Manufacturer—We source from trusted manufacturers who vet raw materials for purity and use diamond grinding wheels to machine precise edges. This keeps cutting surfaces smooth and free of microscopic burrs. Because our suppliers clean their wheels more often than other manufacturers, each countersink is consistently ground to create uniform holes every time.
    Countersinks
    Counterbore Collars
    Uncoated
    Body
    Dia.
    For Drill
    Bit Size
    For Screw
    Size
    Overall
    Lg.
    Mfr.
    Each
    OD
    Wd.
    Each
    4 Flutes
     
    82° Countersink Angle
    1/4"3/32"No. 3
    		3/4"W. L. Fuller2785A120000001/2"1/4"2903A1100000
    5/16"7/64"No. 4
    		7/8"W. L. Fuller2785A13000009/16"1/4"2903A120000
    3/8"1/8"No. 5
    		7/8"W. L. Fuller2785A2100005/8"1/4"2903A130000
    3/8"9/64"No. 6
    		7/8"W. L. Fuller2785A2200005/8"1/4"2903A130000
    3/8"5/32"No. 7
    		7/8"W. L. Fuller2785A2300005/8"1/4"2903A130000
    3/8"11/64"No. 8
    		7/8"W. L. Fuller2785A2400005/8"1/4"2903A130000
    3/8"3/16"No. 9
    		7/8"W. L. Fuller2785A2500005/8"1/4"2903A130000
    3/8"13/64"No. 10
    		7/8"W. L. Fuller2785A2600005/8"1/4"2903A130000
    3/8"7/32"No. 12
    		7/8"W. L. Fuller2785A2700005/8"1/4"2903A130000
    7/16"13/64"No. 10
    		7/8"W. L. Fuller2785A310000011/16"1/4"2903A140000
    1/2"5/32"No. 7
    		7/8"W. L. Fuller2785A35000003/4"1/4"2903A150000
    1/2"3/16"No. 9
    		7/8"W. L. Fuller2785A37000003/4"1/4"2903A150000
    1/2"13/64"No. 10
    		7/8"W. L. Fuller2785A38000003/4"1/4"2903A150000
    1/2"7/32"No. 12
    		7/8"W. L. Fuller2785A39000003/4"1/4"2903A150000
    1/2"1/4"No. 14
    		7/8"W. L. Fuller2785A52000003/4"1/4"2903A150000
    5/8"3/16"No. 9
    		1 1/16"W. L. Fuller2785A53000007/8"1/4"2903A170000
    5/8"1/4"No. 16
    		1 1/16"W. L. Fuller2785A54000007/8"1/4"2903A170000
    5/8"9/32"No. 16
    		1 1/16"W. L. Fuller2785A56000007/8"1/4"2903A170000
    5/8"5/16"No. 18
    		1 1/16"W. L. Fuller2785A58000007/8"1/4"2903A170000
     

    Fast-Cutting Smooth-Finish Drill-Bit Counterbores for Wood

    Image of Product. Front orientation. ZoomedIn view. Counterbores. Fast-Cutting Smooth-Finish Drill-Bit Counterbores for Wood.
    With thin cutting edges to minimize contact with the hole, these counterbores make smooth, accurate cuts at high speeds. Attach them to any drill bit with a 1/2" shank and a cutting diameter of 1/2" or larger. They move up and down the drill bit and lock into place with set screws to match the length of the screw you're installing.
    Carbon SteelAbout Carbon Steel
    Uncoated
    Body
    Dia.
    Overall
    Lg.
    For Shank
    Dia.
    For Min. Drill
    Bit Cutting Dia.
    Each
    1 1/8"1"1/2"1/2"2921A12000000
    1 1/4"1"1/2"1/2"2921A1300000
    1 3/8"1"1/2"1/2"2921A1400000
    1 1/2"1"1/2"1/2"2921A1500000
    1 3/4"1"1/2"1/2"2921A17000000
    2"1 1/4"1/2"1/2"2921A19000000
    2 1/2"1 1/4"1/2"1/2"2921A24000000
     

    Drill-Bit Countersink Sets for Wood and Plastic

    Image of Product. Front orientation. Countersinks. Straight Flute, For Cutting Screw Holes, 1 Countersinking End, For Wood, Drill-Bit Countersink, Sold as Sets.
    These countersinks attach at various points along the drill bit, so one tool will drill countersunk holes for screws of different lengths. They're designed to cut a smooth and even finish in wood and plastic on the first pass.
    Carbon Steel—Stronger than high-speed steel, so it will cut through harder materials. However, high-speed steel is more precise, lasts longer, and cuts at higher speeds.
    Manufacturer—We source from trusted manufacturers who vet raw materials for purity and use diamond grinding wheels to machine precise edges. This keeps cutting surfaces smooth and free of microscopic burrs. Because our suppliers clean their wheels more often than other manufacturers, each countersink is consistently ground to create uniform holes every time.
    82°
    Countersink Angle
    No. of
    Flutes
    Body Dia. Included
    No. of
    Pieces
    For Drill Bit Size
    Finish
    Container
    Type
    Mfr.
    Each
    Carbon Steel
    43/8", 7/16", 1/2"71/8", 9/64", 5/32", 11/64", 3/16", 13/64", 7/32"UncoatedWood StandW. L. Fuller2785A46000000
    43/8", 7/16", 1/2", 5/8"141/8", 9/64", 5/32", 11/64", 3/16", 13/64", 7/32", 1/4", 9/32", 5/16"UncoatedWood StandW. L. Fuller2785A48000000
     

    Adjustable-Diameter Counterbores

    Skip buying different tools to counterbore multiple diameters. Use the set screw on these counterbores to adjust the blades to the diameter you need.
    The included replaceable pilot has the minimum pilot head diameter recommended for use with these counterbores. If your application requires a larger pilot head diameter, choose a Steel Pilot for Changeable-Pilot Counterbores with the same shank diameter as the included pilot. These counterbores require rigid tool holding to prevent breakage and are not for use with hand-held tools.
    High-Speed Steel Blade
    Image of Product. Front orientation. Counterbores. Adjustable-Diameter Counterbores, Round Shank.
    Image of Product. Front orientation. Counterbores. Adjustable-Diameter Counterbores, Morse Taper Shank.

    Round Shank

    Morse Taper Shank

    Durable and wear resistant, these blades make accurate cuts in most materials without chipping or cracking.
    Counterbores
    Replacement
    Counterbore Blades
    Shank
    Body Dia.
    Overall
    Lg.
    Dia.
    Type
    Machine
    Taper No.
    Pilot
    Lg.
    No. of
    Flutes
    Pilot Head
    Dia.
    Pilot Shank
    Dia.
    Each
    Pkg.
    Qty.
    Pkg.
    1" to 1 1/4"4"1/2"Round—0.438"27/16"3/16"3104A11000000023104A310000000
    1 1/4" to 1 5/8"4 3/8"1/2"Round—0.563"29/16"1/4"3104A1400000023104A32000000
    2 1/8" to 2 7/8"6"—Morse TaperMorse 30.750"23/4"3/8"3104A2200000023104A34000000
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