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    20 Products
    About Countersinks
    industrial info icon

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

    Drill-Point Countersink Sets for Screws

    Image of Product. Front orientation. Countersinks. Drill-Point Countersink Sets for Screws.
    Save time by drilling and countersinking your pilot hole in one pass for a range of screw sizes. These countersinks have a small drill point to drill new pilot holes topped with cone-shaped recesses for screw heads.
    High-Speed Steel—These versatile, wear-resistant countersinks cut cleanly in most materials, including plastic, aluminum, and steel.
    82°
    Countersink Angle
    No. of
    Flutes
    No. of
    Pieces
    For Screw Size
    Finish
    Shank
    Type
    Container
    Type
    Each
    High-Speed Steel
    28No. 5, No. 6, No. 8, No. 10, No. 12, 1/4", 5/16", 3/8"
    		UncoatedRoundPlastic Case28145A610000000
     

    Built-In-Pilot Counterbore Sets

    Image of Product. Front orientation. Counterbores. Built-In-Pilot Counterbore Sets.
    Create flat, close-fitting recesses for a range of screw-head sizes. The pilot centers and stabilizes the counterbore for an accurate cut and even surface on the first try.
    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
    Each
    Uncoated High-Speed Steel
    No. 4, No. 5, No. 6, No. 8, No. 10, 1/4", 5/16", 3/8", 7/16", 1/2"
    		10Round42919A120000000
     

    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.
    High-Speed Steel
    Image of Product. Front orientation. Countersinks. Drill-Bit Countersink, 1 Countersinking End, For Wood, For Cutting Screw Holes, Sold Individually, Straight Flute, 4 Flutes.

    4 Flutes

    The choice if you're countersinking lots of holes, these wear-resistant countersinks cut faster and last longer than carbon steel.
    Countersinks
    Counterbore Collars
    Uncoated
    Body
    Dia.
    For Drill
    Bit Size
    For Screw
    Size
    Overall
    Lg.
    Each
    OD
    Wd.
    Each
    4 Flutes
     
    82° Countersink Angle
    3/8"1/8"No. 5
    		7/8"2910A130000005/8"1/4"2903A1300000
     
    90° Countersink Angle
    3/8"1/8"No. 5
    		7/8"2910A73000005/8"1/4"2903A130000
     
    Carbon Steel
    Image of Product. Front orientation. Countersinks. Drill-Bit Countersink, 1 Countersinking End, For Wood, For Cutting Screw Holes, Sold Individually, Straight Flute, 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.
    Countersinks
    Counterbore Collars
    Uncoated
    Body
    Dia.
    For Drill
    Bit Size
    For Screw
    Size
    Overall
    Lg.
    Each
    OD
    Wd.
    Each
    4 Flutes
     
    82° Countersink Angle
    3/8"1/8"No. 5
    		7/8"2785A21000005/8"1/4"2903A1300000
     

    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
    Each
    Uncoated High-Speed Steel
    No. 5, No. 6, No. 8, No. 10, 1/4", 5/16", 3/8", 7/16", 1/2"
    		9Round2Plastic Case9940N1110000000
    No. 5, No. 6, No. 8, No. 10, 1/4", 5/16", 3/8", 7/16", 1/2"
    		9Round2Plastic Case9940N112000000
     

    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.
    Dia.
    Uncoated
    Body
    Shank
    Drill Tip
    Dia.
    For Screw
    Size
    Overall
    Lg.
    Shank
    Type
    Each
    2 Flutes
     
    82° Countersink Angle
    5/16"1/4"0.127"No. 5
    		1 3/4"Round28145A41000000
     

    Built-In-Pilot Counterbores

    The pilot centers the counterbore and prevents wobbling for an accurate cut on the first try. With dimensions that match standard screw-head diameters and thread diameters, this is your plug-and-play option for pilot-driven counterbores.
    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.
    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.
    Dia.
    Lg.
    Overall
    Lg.
    Dia.
    Type
    No. of
    Flutes
    Each
    Each
    No. 5
    		0.205"1/8"0.188"4 1/8"3/16"Round42919A3200000028225A32000000
     

    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 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.
    Overall
    Lg.
    Dia.
    Type
    No. of
    Flutes
    Max. Hole
    Drilling Dp.
    Each
    No. 5
    		0.220"1 7/32"1/4"Round20.25"29445A11000000
    No. 5
    		0.220"2"1/4"Round20.414"29445A31100000
     

    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 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.
    Dia.
    Lg.
    Overall
    Lg.
    Dia.
    Type
    No. of
    Flutes
    Each
    Each
     
    1/64" Oversize
    No. 5
    		0.221"0.141"0.188"4 1/8"3/16"Round42919A5200000028225A52000000
     
    1/32" Oversize
    No. 5
    		0.236"0.156"0.188"4 1/8"3/16"Round42919A720000028225A7200000
     

    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
    No. of
    Pieces
    Oversize
    Amount
    Shank
    Type
    No. of
    Flutes
    Each
    Uncoated High-Speed Steel
    No. 4, No. 5, No. 6, No. 8, No. 10, 1/4", 5/16", 3/8", 7/16", 1/2"
    		101/64"Round42919A140000000
    No. 4, No. 5, No. 6, No. 8, No. 10, 1/4", 5/16", 3/8", 7/16", 1/2"
    		101/32"Round42919A16000000
     

    Counterbores for High-Profile Rounded-Head Screws

    Cut flat, close-fitting recesses for fillister-head screws. These counterbores cut deeply enough for screws with tall head profiles to sit flush with the surface.
    High-Speed Steel
    Image of Product. Front orientation. Counterbores. Counterbores for High-Profile Rounded-Head Screws.
    Durable and wear resistant, these counterbores make accurate cuts in most materials without chipping or cracking.
    Uncoated
    For Screw
    Size
    Body
    Dia.
    Overall
    Lg.
    Shank
    Type
    No. of
    Flutes
    Pilot
    Lg.
    Each
    No. 5
    		0.220"2 5/8"Round20.220"2909A16000000
     
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