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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.

    Pilot Type

    Counterbore Type

    Size Designation

    Sold As

    Drill-Point Counterbore Sets

    Image of Product. Front orientation. Counterbores. Drill-Point Counterbore Sets.
    Skip a step when installing screws of various thread diameters in metal. With a sharp point on the tip, these counterbores drill a pilot hole topped with a flat recess for the screw head. That's faster and more accurate than switching to a counterbore in between passes with your drill bit.
    High-Speed Steel—Durable and wear resistant, these counterbores make accurate cuts in most materials without chipping or cracking.
    For Screw Size
    Overall Length
    Shank
    Type
    No. of
    Flutes
    No. of
    Pieces
    Container
    Type
    Mfr.
    Each
    Uncoated High-Speed Steel
    M3, M4, M5, M6, M8, M10, M12, M14, M16
    		1.28125", 1.40625", 1.5625", 1.625", 1.90625", 2.15625", 2.5625", 2.84375", 3.5"Round29Plastic CaseLink Industries9940N1130000000
     

    Oversized Counterbores

    Designed to give screw heads a slightly loose fit, these counterbores are a bit wider than standard sizes. The extra clearance prevents binding and leaves room for a seal or O-ring around the screw head.
    High-Speed SteelAbout High-Speed Steel
    Image of Product. Front orientation. ZoomedIn view. Counterbores. Oversized Counterbores.
    Durable and wear resistant, these counterbores make accurate cuts in most materials without chipping or cracking.
    Titanium Nitride (TiN) Coated—Withstand heat, corrosion, and abrasion for longer than uncoated counterbores, so the cutting edges stay sharper.
    Pilot
    Shank
    Uncoated
    Titanium Nitride
    (TiN) Coated
    For Screw
    Size
    Body Dia.,
    mm
    Dia.,
    mm
    Lg.
    Overall
    Lg.
    Dia.
    Type
    No. of
    Flutes
    Mfr.
    Each
    Each
    0.5 mm Oversize
    M4
    		7.54.50.250"5"1/4"Round4Alvord-Polk Tool2740A1200000028225A92000000
     

    Oversized Counterbore Sets

    Image of Product. Front orientation. Counterbores. Oversized Counterbore Sets.
    Designed to give screw heads a slightly loose fit, these counterbores are a bit wider than standard sizes. The extra clearance prevents binding and leaves room for a seal or O-ring around the screw head.
    High-Speed Steel—Durable and wear resistant, these counterbores make accurate cuts in most materials without chipping or cracking.
    For Screw Size
    Oversize
    Amount, mm
    Shank
    Type
    No. of
    Flutes
    No. of
    Pieces
    Mfr.
    Each
    Uncoated High-Speed Steel
    M3, M4, M5, M6, M8, M10, M12, M14
    		0.5Round48Alvord-Polk Tool2740A190000000
     

    Drill-Point Counterbores

    Skip a step when installing screws in metal. With a sharp point on the tip, these counterbores drill a pilot hole topped with a flat recess for the screw head. That's faster and more accurate than switching to a counterbore in between passes with your drill bit.
    High-Speed SteelAbout High-Speed Steel
    Image of Product. Front orientation. Counterbores. Drill-Point Counterbores.
    Durable and wear resistant, these counterbores make accurate cuts in most materials without chipping or cracking.
    Shank
    Uncoated
    For Screw
    Size
    Body Dia.,
    mm
    Drill Tip
    Dia., mm
    Overall
    Lg.
    Dia.
    Type
    No. of
    Flutes
    Max. Hole Drilling
    Dp., mm
    Mfr.
    Each
    M4
    		7.54.361 3/8"1/4"Round27.54Link Industries29445A22000000
     

    Built-in-Pilot Counterbores

    A pilot centers these counterbores and prevents wobbling for an accurate cut on the first try. With dimensions that match standard screw-head diameters and thread diameters, they are your plug-and-play option for pilot-driven counterbores.
    Metric counterbores have undersized pilots to meet DIN standards.
    High-Speed SteelAbout High-Speed Steel
    Image of Product. Front orientation. ZoomedIn view. Counterbores. Built-in-Pilot Counterbores.
    Durable and wear resistant, these counterbores make accurate cuts in most materials without chipping or cracking.
    Pilot
    Shank
    Uncoated
    For Screw
    Size
    Body Dia.,
    mm
    Dia.,
    mm
    Lg.
    Overall
    Lg.
    Dia.
    Type
    No. of
    Flutes
    Mfr.
    Each
    M4
    		8.03.30.197"2 3/4"3/16"Round3Dormer Pramet2919A27000000
     
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