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    26 Products

    Fluteless Smooth-Finish Countersinks with Pilot for Screws

    Cut a smooth, accurate seat for your screw head on the first pass. The built-in pilot centers the countersink while the hollow body prevents chip buildup, vibration, and wobbling.
    High-Speed SteelAbout High-Speed Steel
    Image of Product. Front orientation. Countersinks. Fluteless Smooth-Finish Countersinks with Pilot for Screws, 0 Flutes.

    0 Flutes

    These versatile, wear-resistant countersinks cut cleanly in most materials, including plastic, aluminum, and steel.
    Dia.
    Pilot
    Uncoated
    For Hole Dia.
    Body
    Shank
    Dia.
    Lg.
    For Screw
    Size
    Overall
    Lg.
    Shank
    Type
    Mfr.
    Each
    0 Flutes
     
    82° Countersink Angle
    1/2" to 15/16"15/16"1/2"1/2"1/4"1/2"
    2 11/16"Round
    Republic Drill2739A73000000
     

    Drill-Point Counterbores Sets

    Image of Product. Front orientation. Counterbores. Drill-Point Counterbores 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
    No. 5, No. 6, No. 8, No. 10, 1/4", 5/16", 3/8", 7/16", 1/2"
    1.21875", 1.21875", 1.46875", 1.5", 1.75", 1.9375", 2.34375", 2.5", 2.6875"Round
    29Plastic CaseLink Industries9940N1110000000
    No. 5, No. 6, No. 8, No. 10, 1/4", 5/16", 3/8", 7/16", 1/2"
    2", 2", 2.25", 2.25", 2.75", 3", 3.5", 4", 4.5"Round
    29Plastic CaseLink Industries9940N112000000
     

    Countersink Drill Bits for Screws

    Image of Product. Side1 orientation. Contains Annotated. Countersink Drill Bits. Countersink Drill Bits for Screws.
    Also known as step drill bits, these bits countersink as they drill. The 82° countersink angle is compatible with the profile of flat- and oval-head inch screws. After multiple sharpenings, the drill bit diameter may become smaller.
    Uncoated High-Speed Steel—These versatile, wear-resistant drill bits cut cleanly in most materials, including plastic, aluminum, and steel.
    Dia.
    Lg.
    82°
    Countersink Angle
    For Screw
    Size
    Body
    Step
    Step
    Overall
    Shank
    Dia.
    Point
    Angle
    For Use On
    Mfr.
    Each
    Uncoated High-Speed Steel
     
    2 Flutes
    1/2"
    7/8"0.510"1"5 1/2"0.8750"118°Aluminum, Brass, Bronze, Iron, Plastic, Stainless Steel, SteelRepublic Drill8914A570000000
     

    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
    Shank
    Type
    No. of
    Flutes
    No. of
    Pieces
    Mfr.
    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"
    Round
    410Alvord-Polk Tool2919A120000000
     

    Carbide-Insert Counterbores

    Image of ProductInUse. Shown with Inserts (Sold Separately). Front orientation. Counterbores. Carbide-Insert Counterbores.

    Shown with Inserts (Sold

    Separately)

    Pair these counterbores with an insert (sold separately) to cut hundreds of precise holes with the same tool. When the cutting edges dull, replace the insert instead of the counterbore to reduce costs during high-volume jobs. Secure the insert with the included screw so it stays in place, even at the high speeds of your CNC machine. These counterbores create flat-bottomed holes that allow socket head screws to sit flush with your surface.
    SteelAbout Steel
    Counterbores
    Replacement
    Insert Screws
    Shank
    For Screw
    Size
    Body
    Dia.
    Overall
    Lg.
    Dia.
    Type
    Max. Hole
    Drilling Dp.
    No. of Inserts
    Req.
    Mfr.
    Each
    Pkg.
    Qty.
    Pkg.
    1/2"
    0.797"3 1/4"3/4"Round
    0.79"2Kyocera8129N1210000000108129N133000000
     
    Required Counterbore Inserts

    Counterbore Drill Bits

    Image of Product. Front orientation. Contains Annotated. Counterbore Drill Bits. Counterbore Drill Bits.
    Often called step drill bits, these cut a pilot hole and counterbore in a single pass to eliminate tool changes and ensure precise alignment. Made of high-speed steel, they handle a wide range of materials, including aluminum, plastic, and stainless steel. They can be resharpened to extend tool life. The body diameter may decrease after multiple sharpenings.
    Dia.
    Lg.
    For Screw
    Size
    Body
    Step
    Step
    Overall
    Point
    Angle
    For Use On
    Mfr.
    Each
    Uncoated High-Speed Steel
    1/2"
    0.781"0.531"1"9 7/8"118°Aluminum, Brass, Bronze, Iron, Plastic, Stainless Steel, SteelRepublic Drill8914A370000000
     

    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.
    Drill Tip
    Dia.
    Overall
    Lg.
    Dia.
    Type
    No. of
    Flutes
    Max. Hole
    Drilling Dp.
    Mfr.
    Each
    1/2"
    0.781"0.532"2 11/16"5/8"Round
    20.562"Link Industries29445A19000000
    1/2"
    0.781"0.532"4 1/2"1/2"Round
    21.596"Link Industries29445A319000000
     

    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.
    Dia.
    Lg.
    Overall
    Lg.
    Dia.
    Type
    No. of
    Flutes
    Mfr.
    Each
    Each
    1/64" Oversize
    1/2"
    0.773"0.515"0.500"7 1/2"1/2"Round
    4Alvord-Polk Tool2919A6100000028225A610000000
     
    1/32" Oversize
    1/2"
    0.788"0.531"0.500"7 1/2"1/2"Round
    4Alvord-Polk Tool2919A810000028225A81000000
     
    Carbide-Tipped Steel
    Image of Product. Front orientation. ZoomedIn view. Counterbores. Oversized Counterbores.
    The hardest and most wear-resistant counterbores we offer. These bits stay sharper at higher temperatures and faster speeds for the best performance on hard and abrasive materials.
    Pilot
    Shank
    Uncoated
    For Screw
    Size
    Body
    Dia.
    Dia.
    Lg.
    Overall
    Lg.
    Dia.
    Type
    No. of
    Flutes
    Mfr.
    Each
    1/64" Oversize
    1/2"
    0.773"33/64"0.500"7 1/2"1/2"Round
    3Rock River Tool3218A1530000000
     
    1/32" Oversize
    1/2"
    0.788"17/32"0.500"7 1/2"1/2"Round
    3Rock River Tool3218A152000000
     

    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.
    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
    Mfr.
    Each
    Each
    1/2"
    0.757"1/2"0.500"7 1/2"1/2"Round
    4Alvord-Polk Tool2919A4100000028225A410000000
     
    Cobalt SteelAbout Cobalt Steel
    Image of Product. Front orientation. ZoomedIn view. Counterbores. Built-in-Pilot Counterbores.
    Tougher and more wear resistant than high-speed steel counterbores, these counterbores last at least twice as long. They can also run up to 25% faster at higher temperatures without chipping on hard materials, such as nickel.
    Pilot
    Shank
    Uncoated
    For Screw
    Size
    Body
    Dia.
    Dia.
    Lg.
    Overall
    Lg.
    Dia.
    Type
    No. of
    Flutes
    Mfr.
    Each
    1/2"
    0.757"1/2"0.500"6"1/2"Round
    3Keo11162N210000000
     
    Carbide-Tipped Steel
    Image of Product. Front orientation. ZoomedIn view. Counterbores. Built-in-Pilot Counterbores.
    The hardest and most wear-resistant counterbores we offer. These bits stay sharper at higher temperatures and faster speeds for the best performance on hard and abrasive materials.
    Pilot
    Shank
    Uncoated
    For Screw
    Size
    Body
    Dia.
    Dia.
    Lg.
    Overall
    Lg.
    Dia.
    Type
    No. of
    Flutes
    Mfr.
    Each
    1/2"
    0.757"1/2"0.500"7 1/2"1/2"Round
    3Rock River Tool3218A1510000000
     

    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
    Shank
    Type
    No. of
    Flutes
    No. of
    Pieces
    Mfr.
    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"
    1/64"Round
    410Alvord-Polk Tool2919A140000000
    No. 4, No. 5, No. 6, No. 8, No. 10, 1/4", 5/16", 3/8", 7/16", 1/2"
    1/32"Round
    410Alvord-Polk Tool2919A16000000
     

    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.
    Titanium Nitride (TiN) Coated—Withstand heat, corrosion, and abrasion better than uncoated and black oxide countersinks, so they stay sharp over longer periods.
    Number of Flutes—Countersinks with fewer flutes are best for aggressive cutting. They leave more room for chips to clear, reducing friction and heat. Countersinks with more flutes spread the cut across more edges for better stability, a smoother finish, and longer tool life.
    Dia.
    Uncoated
    Titanium Nitride
    (TiN) Coated
    Body
    Shank
    Drill Tip
    Dia.
    For Screw
    Size
    Overall
    Lg.
    Shank
    Type
    Mfr.
    Each
    Each
    2 Flutes
     
    82° Countersink Angle
    1"1/2"0.503"1/2"
    3"Round
    Link Industries28145A3100000011206N31000000
     
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