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    27 Products
    About Countersinks
    industrial info icon

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

    Drill-Point Countersinks for Screws

    Save time by drilling a pilot hole and countersinking in a single step. These countersinks have a small drill point to drill new pilot holes topped with cone-shaped recesses for screw heads.
    High-Speed Steel
    Image of Product. Front orientation. Countersinks. Drill-Point Countersinks for Screws, 2 Flutes.

    2 Flutes

    These versatile, wear-resistant countersinks cut cleanly in most materials, including plastic, aluminum, and steel.
    Number of Flutes—Countersinks with fewer flutes reduce chatter, so you can run them at high speeds. Countersinks with a higher number of flutes remove more material per revolution, leaving a smoother finish and extending tool life.
    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.
    Dia.,
    mm
    Uncoated
    Body
    Shank
    Drill Tip
    Dia., mm
    For Screw
    Size
    Overall
    Lg., mm
    Shank
    Type
    Mfr.
    Each
    2 Flutes
     
    90° Countersink Angle
    6.356.353.10M3
    		44.44RoundLink Industries28145A71000000
    8.206.354.10M4
    		44.44RoundLink Industries28145A7200000
    11.107.935.10M5
    		50.79RoundLink Industries28145A7300000
    12.707.936.10M6
    		50.79RoundLink Industries28145A7400000
    17.4511.118.10M8
    		66.66RoundLink Industries28145A7500000
    20.6312.710.10M10
    		76.19RoundLink Industries28145A7600000
    25.4015.8712.10M12
    		76.19RoundLink Industries28145A7700000
     

    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.
    Pilot
    Shank
    Uncoated
    For Screw
    Size
    Body Dia.,
    mm
    Dia.,
    mm
    Lg.
    Overall
    Lg.
    Dia.
    Type
    No. of
    Flutes
    Mfr.
    Each
     
    0.5 mm Oversize
    M3
    		6.03.50.219"4 1/2"3/16"Round4Alvord-Polk Tool2740A11000000
    M4
    		7.54.50.250"5"1/4"Round4Alvord-Polk Tool2740A1200000
    M5
    		9.05.50.281"5 5/8"5/16"Round4Alvord-Polk Tool2740A1300000
    M6
    		10.56.50.313"5 5/8"5/16"Round4Alvord-Polk Tool2740A1400000
    M8
    		13.58.50.375"6 1/2"1/2"Round4Alvord-Polk Tool2740A1500000
    M10
    		16.510.50.500"7"1/2"Round4Alvord-Polk Tool2740A1600000
    M12
    		18.512.50.500"7 1/8"1/2"Round4Alvord-Polk Tool2740A1700000
    M14
    		21.514.50.563"7 1/2"5/8"Round4Alvord-Polk Tool2740A18000000
    M16
    		24.516.50.625"7 5/8"5/8"Round4Alvord-Polk Tool2740A22000000
    M20
    		30.520.50.750"8 1/8"7/8"Round4Alvord-Polk Tool2740A26000000
     

    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
    No. of
    Pieces
    Shank
    Type
    No. of
    Flutes
    Container
    Type
    Mfr.
    Each
    Uncoated High-Speed Steel
    M3, M4, M5, M6, M8, M10, M12, M14, M16
    		9Round2Plastic CaseLink Industries9940N1130000000
     

    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
    Overall
    Lg.
    Dia.
    Type
    No. of
    Flutes
    Max. Hole Drilling
    Dp., mm
    Mfr.
    Each
    M3
    		5.91 1/4"1/4"Round26.35Link Industries29445A21000000
    M4
    		7.51 3/8"1/4"Round27.54Link Industries29445A2200000
    M5
    		9.11 1/2"5/16"Round27.94Link Industries29445A2300000
    M6
    		10.71 9/16"5/16"Round29.52Link Industries29445A2400000
    M8
    		13.41 13/16"7/16"Round211.11Link Industries29445A2500000
    M10
    		16.62 1/16"1/2"Round214.29Link Industries29445A2600000
    M12
    		18.72 7/16"5/8"Round215.87Link Industries29445A2700000
    M14
    		21.82 5/8"5/8"Round216.67Link Industries29445A2800000
    M16
    		24.62 3/4"5/8"Round217.46Link Industries29445A2900000
     
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