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    6 Products
    About Counterbores
    industrial info icon

    Create flat-bottomed holes, so your screw heads sit flush, recessed, or slightly raised.

    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.
    Mfr.
    Each
    Pkg.
    Qty.
    Pkg.
    1" to 1 1/4"4"1/2"Round—0.438"27/16"3/16"Alvord-Polk Tool3104A11000000023104A310000000
    1 1/4" to 1 5/8"4 3/8"1/2"Round—0.563"29/16"1/4"Alvord-Polk Tool3104A1400000023104A32000000
    2 1/8" to 2 7/8"6"—Morse TaperMorse 30.750"23/4"3/8"Alvord-Polk Tool3104A2200000023104A34000000
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