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    40 Products

    Collet Fixtures

    Pair these fixtures with collets to tightly grip workpieces for machining. You can mount them on milling machines, drill presses, and other work surfaces. However, they’re not for use with lathes, grinders, or high-speed rotary tables. All have a through hole to accommodate long workpieces.
    Collet Nut Actuator
    Image of Product. Front orientation. Collet Fixtures. Collet Fixtures, Collet Nut Actuator.
    Collet nut fixtures convert ER collets—typically used to hold tool bits—into holders for cylindrical workpieces. The tapered, slit design of the collet distributes clamping force evenly around a workpiece. This creates a stable, consistent grip that keeps your workpiece from shifting, even under 5-axis machining forces. These fixtures are made of steel to withstand the high clamping forces and frequent cycles of production environments.
    Mounting
    Holes
    For Collet
    Type
    For Max. Workpiece
    Dia.
    Through-Hole
    Dia.
    Dia.
    Ht.
    Material
    No.
    of
    Dia.
    Bolt Circle
    Dia.
    Mounting Position
    Power
    Source
    Each
    ER-255/8"7/16"2 3/4"2 1/2"Black-Oxide Steel41/4"2 1/8"Horizontal, VerticalManual3174A360000000
    ER-255/8"11/16"5"3"Black-Oxide Steel47/16"4"Horizontal, VerticalManual3174A37000000

    CAT Taper Collet Chucks

    Hold collets tightly in CNC machines with CAT taper spindles for milling, drilling, and routing. Made from high-grade hardened steel, these chucks remain rigid and accurate while resisting wear—even at high speeds. The shank on these chucks is precision ground to the industry standard AT3 tolerance—or better—for a secure fit that minimizes runout in your machine spindle. To ensure compatibility across machines, these chucks meet ANSI/ASME standards for CAT spindles. Insert your collet and tighten the nut to clamp your tool in place. Internal threads on the shank let you attach a retention knob, so you can connect these chucks to your machine’s drawbar system.
    All chucks can deliver coolant to your tool’s cutting edge to clear chips and extend tool life. If you have a machine that sends coolant through the spindle, pair them with an ER coolant control collet for the best results.
    To maximize grip and minimize runout, choose a chuck where your tool diameter falls in the middle of the bit shank size range.
    Chucks balanced to G 2.5 vibrate less than chucks balanced to G 6.3, so your collets, bits, and spindle will last longer. Chucks balanced to G 6.3 are a cost-effective option that is good for most machining tasks.
    CAT 40 Machine Taper
    Image of Product. Front orientation. Contains Annotated. Milling Machine Collet Chucks. CAT Taper Collet Chucks.
    Collet Stop Screw—Chucks with a collet stop screw set the tool depth in the chuck for consistent, repeatable performance when you change tools.
    RFID Chip Hole—Chucks with an RFID chip hole hold a small RFID tag for automatic tool identification and tracking.
    Milling Machine Collet Chucks
    Wrenches
    Replacement Nuts
    For Collet
    Type
    For Bit Shank
    Size
    Projection
    Total Indicated Runout
    (TIR) Accuracy
    Collet Nut Type
    Coolant Delivery Type
    Features
    Specs.
    Met
    Each
    Each
    Each
    2.5 mm/s @ 25,000 rpm
     
    Hardened Nickel Chrome-Moly Steel
    ER-250.039" to 0.629"2.5"0.0001"Bearing Slotted NutThrough BoreCollet Stop Screw, RFID Chip HoleASME B5.505699N12100000005699N1280000006163N114000000
    ER-250.039" to 0.629"6"0.0001"Bearing Slotted NutThrough BoreCollet Stop Screw, RFID Chip HoleASME B5.505699N1230000005699N128000006163N11400000
     
    6.3 mm/s @ 15,000 rpm
     
    Hardened Nickel Chrome-Moly Steel
    ER-250.039" to 0.629"2.5"0.0001"Slotted NutFlange Entry, Through BoreCollet Stop ScrewASME B5.509493N29000005699N128000009502N2100000
    ER-250.039" to 0.629"4"0.0001"Slotted NutFlange Entry, Through BoreCollet Stop ScrewASME B5.509493N310000005699N128000009502N2100000
    ER-250.039" to 0.629"6"0.0001"Slotted NutFlange Entry, Through BoreCollet Stop ScrewASME B5.509493N320000005699N128000009502N2100000
    ER-250.039" to 0.629"8"0.0001"Slotted NutFlange Entry, Through BoreCollet Stop ScrewASME B5.509493N330000005699N128000009502N2100000
     
    CAT 50 Machine Taper
    Image of Product. Front orientation. Contains Annotated. Milling Machine Collet Chucks. CAT Taper Collet Chucks.
    Collet Stop Screw—Chucks with a collet stop screw set the tool depth in the chuck for consistent, repeatable performance when you change tools.
    Milling Machine Collet Chucks
    Wrenches
    Replacement Nuts
    For Collet
    Type
    For Bit Shank
    Size
    Projection
    Total Indicated Runout
    (TIR) Accuracy
    Collet Nut
    Type
    Coolant Delivery Type
    Features
    Specs.
    Met
    Each
    Each
    Each
    6.3 mm/s @ 15,000 rpm
     
    Hardened Nickel Chrome-Moly Steel
    ER-250.039" to 0.629"4"0.0001"Slotted NutFlange Entry, Through BoreCollet Stop ScrewASME B5.509493N4500000005699N1280000009502N21000000
    ER-250.039" to 0.629"6"0.0001"Slotted NutFlange Entry, Through BoreCollet Stop ScrewASME B5.509493N460000005699N128000009502N2100000
     

    Straight-Shank Collet Chucks

    Extend your tool holder’s reach or adapt it to fit different collet systems on manual and CNC lathes and machining centers. Made from hardened alloy steel, these chucks remain rigid and accurate while resisting wear—even at high speeds. Their shank is also precision ground for a secure fit that minimizes runout in your machine spindle. Insert your collet and tighten the nut to clamp your tool in place.
    These chucks have a collet stop screw that sets the tool depth in the chuck for consistent, repeatable performance when you change tools. They’re also through-bore coolant-compatible, so they can route coolant through their center to clear chips, improve the finish of your workpiece, and extend the life of your tool. If you have a machine that sends coolant through the spindle, pair them with an ER coolant control collet for the best results.
    To maximize grip and minimize runout, choose a chuck where your tool diameter falls in the middle of the bit shank size range.
    Hardened Alloy Steel
    Image of System. Shown with Tool Holder and Cutting Bit (Not Included). Side1 orientation. Contains Annotated. Milling Machine Collet Chucks. Straight-Shank Collet Chucks.
    Image of ProductInUse. Assembly Shown in Use on Workpiece. Side1 orientation. Milling Machine Collet Chucks. Straight-Shank Collet Chucks.

    Shown with Tool Holder

    and Cutting Bit (Not

    Included)

    Assembly Shown in

    Use on Workpiece

    Image of Product. For DA Collets. Front orientation. Contains Annotated. Milling Machine Collet Chucks. Straight-Shank Collet Chucks.

    For DA Collets

    Image of Product. For TG Collets. Front orientation. Contains Annotated. Milling Machine Collet Chucks. Straight-Shank Collet Chucks.

    For TG Collets

    Image of Product. For ER Collets. Front orientation. Contains Annotated. Milling Machine Collet Chucks. Straight-Shank Collet Chucks.

    For ER Collets

    Milling Machine Collet Chucks
    Wrenches
    Replacement Nuts
    For Collet
    Type
    For Bit Shank
    Size
    Shank Lg.
    Projection
    Overall Lg.
    Collet Nut
    Dia.
    Max. Body
    Dia.
    Total Indicated Runout
    (TIR) Accuracy
    Collet Nut Type
    Features
    Each
    Each
    Each
    Through Bore Coolant Delivery
     
    3/4" Diameter Shank
    ER-250.039" to 0.629"3.94" (100 mm)1.93"5.87" (149 mm)1.38" (35 mm)1.19"0.0001"Miniature Coated Slotted NutCollet Stop Screw9535N480000000———09502N43000000
    ER-250.039" to 0.629"5" (127 mm)1.85"6.85" (174 mm)1.65" (42 mm)1.65"0.0001"Slotted NutCollet Stop Screw9535N370000005699N1280000009502N3500000
     
    1" Diameter Shank
    ER-250.039" to 0.629"5" (127 mm)1.85"6.85" (174 mm)1.65" (42 mm)1.65"0.0001"Slotted NutCollet Stop Screw9535N410000005699N128000009502N3500000
    ER-250.039" to 0.629"5.51" (140 mm)1.97"7.48" (190 mm)1.38" (35 mm)1.19"0.0001"Miniature Coated Slotted NutCollet Stop Screw9535N49000000———09502N4300000
     
    1 1/4" Diameter Shank
    ER-250.039" to 0.629"5" (127 mm)1"6" (152 mm)1.65" (42 mm)1.25"0.0001"Slotted NutCollet Stop Screw9535N430000005699N128000009502N3500000
     

    BT Taper Collet Chucks

    Hold collets tightly in CNC machines with BT taper spindles when milling, drilling, and routing. Made from high-grade chrome-moly steel, these chucks remain rigid and accurate while resisting wear—even at high speeds. Their shank is also precision ground to the industry standard AT3 tolerance for a secure fit that minimizes runout in your machine spindle. These chucks meet JIS or MAS standards for compatibility across machines with BT spindles. Internal threads on the shank let you attach a retention knob, so you can connect these chucks to your machine’s drawbar system. Insert your collet and tighten the nut to clamp your tool in place.
    You can route coolant through them to extend the life of your bit and clear chips. If your machine has a through-spindle coolant system (TSC), use these chucks with an ER coolant control collet for the best results.
    To maximize grip and minimize runout, choose a chuck where your tool diameter falls in the middle of the bit shank size range.
    Chucks balanced to G 2.5 vibrate less than chucks balanced to G 6.3, so your collets, bits, and spindle will last longer. Chucks balanced to G 6.3 are a cost-effective option that is good for most machining tasks.
    BT 30 Machine Taper
    Image of Product. Front orientation. Contains Annotated. Milling Machine Collet Chucks. BT Taper Collet Chucks.
    RFID Chip Hole—Chucks with an RFID chip hole can hold a small RFID tag for automatic tool identification and tracking.
    Milling Machine Collet Chucks
    Wrenches
    Replacement Nuts
    For Collet
    Type
    For Bit Shank
    Size
    Projection
    Total Indicated Runout
    (TIR) Accuracy
    Collet Nut Type
    Coolant Delivery
    Type
    Features
    Specs.
    Met
    JIS
    Specification
    Each
    Each
    Each
    2.5 mm/s @ 25,000 rpm
     
    Hardened Chrome-Moly Steel
    ER-250.039" to 0.629"2.76" (70 mm)0.0001"Coated Slotted NutThrough BoreRFID Chip HoleISO 7388-2JIS B 63399483N1500000005699N1280000009615N35000000
     
    BT 40 Machine Taper
    Image of Product. Front orientation. Contains Annotated. Milling Machine Collet Chucks. BT Taper Collet Chucks.
    Collet Stop Screw—Chucks with a collet stop screw set the tool depth in the chuck for consistent, repeatable performance when you change tools.
    RFID Chip Hole—Chucks with an RFID chip hole can hold a small RFID tag for automatic tool identification and tracking.
    Milling Machine Collet Chucks
    Wrenches
    Replacement Nuts
    For Collet
    Type
    For Bit Shank
    Size
    Projection
    Total Indicated Runout
    (TIR) Accuracy
    Collet Nut Type
    Coolant Delivery Type
    Features
    Specs.
    Met
    JIS
    Specification
    Each
    Each
    Each
    2.5 mm/s @ 25,000 rpm
     
    Hardened Chrome-Moly Steel
    ER-250.039" to 0.629"2.76" (70 mm)0.0001"Coated Slotted NutThrough BoreRFID Chip HoleISO 7388-2JIS B 63399483N2300000005699N1280000009615N35000000
    ER-250.039" to 0.629"3.94" (100 mm)0.0001"Coated Slotted NutThrough BoreRFID Chip HoleISO 7388-2JIS B 63399483N240000005699N128000009615N3500000
     
    6.3 mm/s @ 15,000 rpm
     
    Hardened Nickel Chrome-Moly Steel
    ER-250.039" to 0.629"2.5"0.0001"Slotted NutFlange Entry, Through BoreCollet Stop ScrewJIS B 63399483N34000005699N128000009502N2100000
    ER-250.039" to 0.629"4"0.0001"Slotted NutFlange Entry, Through BoreCollet Stop ScrewJIS B 63399483N350000005699N128000009502N2100000
     

    Tool Holder Cleaning Tools

    Keep your tool holder debris-free to maintain tight tolerances, ensure uniform clamping, and prevent vibration and wear that shortens tool and machine life. These cleaners wipe away chips, lubricants, and fine dust better than rags, cleaners, and degreasers. Precisely sized to your tool holder or bore, just insert them and rotate them by hand to wipe the surface clean.
    For Tool Holder Bores—Tapered
    Image of ProductInUse. Side1 orientation. CrossSection view. Contains Annotated. Tool Holder Cleaning Tools. For Tool Holder Bores—Tapered.
    Image of Product. Front orientation. Tool Holder Cleaning Tools. For Tool Holder Bores—Tapered.
    Cleaners for tool holder bores clean the inside of tool holders.
    Those for tapered bores are shaped to clean the inside of collet chucks and fixtures.
    For
    Dia.
    For Collet
    Type
    Min.
    Max.
    Taper
    Lg.
    Overall
    Lg.
    Material
    Each
    ER-250.71"0.98"1.35"2 5/8"Plastic9399N26000000
     

    NMTB Taper Collet Chucks

    Image of Product. Front orientation. Milling Machine Collet Chucks. NMTB Taper Collet Chucks.
    Hold collets tightly in older CNC machines with NMTB taper spindles for milling, drilling, and routing. The shank on these chucks is precision ground to the industry standard AT3 tolerance—or better—for a secure fit that minimizes runout in your machine spindle. Internal threads in the shank connect to your machine's drawbar.
    Insert your collet and tighten the nut to clamp your tool in place.
    To maximize grip and minimize runout, choose a chuck where your tool diameter falls in the middle of the bit shank size range.
    Collet Stop Screw—Chucks with a collet stop screw set the tool depth in the chuck for consistent, repeatable performance when you change tools.
    Milling Machine Collet Chucks
    Wrenches
    Replacement Nuts
    For Collet
    Type
    For Bit Shank
    Size
    Projection
    Total Indicated Runout
    (TIR) Accuracy
    Material
    Collet Nut
    Type
    Coolant Delivery
    Type
    Features
    Specs.
    Met
    Each
    Each
    Each
    NMTB 40 Machine Taper
    ER-250.039" to 0.629"2"0.0001"Hardened Alloy SteelSlotted NutThrough BoreCollet Stop ScrewASME B5.189514N1400000005699N1280000009502N35000000
     

    R8 Taper Collet Chucks

    Image of Specification. Front orientation. Contains Annotated. Milling Machine Collet Chucks. R8 Taper Collet Chucks.
    Hold collets tightly in Bridgeport and other manual machines with R8 spindles to grip tools for milling, drilling, and routing. These chucks let you use the same ER or TG collets as other machines. This reduces the number of collets you need while also giving you a strong grip on your tools. Insert your collet and tighten the nut to clamp your tool in place. Internal threads on the shank let you connect them to your machine’s drawbar system.
    To maximize grip and minimize runout, choose a chuck where your tool diameter falls in the middle of the bit shank size range.
    Collet Stop Screw—Chucks with a collet stop screw set the tool depth in the chuck for consistent, repeatable performance when you change tools.
    Milling Machine Collet Chucks
    Wrenches
    Replacement Nuts
    For Collet
    Type
    For Bit Shank
    Size
    Projection
    Total Indicated Runout
    (TIR) Accuracy
    Material
    Collet Nut
    Type
    Features
    Each
    Each
    Each
    ER-250.039" to 0.629"2.5"0.0001"Hardened Alloy SteelSlotted NutCollet Stop Screw9523N1500000005699N1280000009502N35000000
     

    Dual-Contact CAT Taper Collet Chucks

    Image of Product. Front orientation. Contains Annotated. Milling Machine Collet Chucks. Dual-Contact CAT Taper Collet Chucks.
    Hold collets tightly in CNC machines with dual-contact CAT taper spindles for milling, drilling, and routing. These chucks contact both the taper and spindle face for a more rigid hold than standard chucks. The added rigidity improves accuracy and surface finish while reducing vibration. Made from high-grade nickel chrome-moly steel, these chucks remain stable and accurate while resisting wear—even at high speeds. They’re balanced to G 2.5, further reducing vibration to extend the life of your collets, bits, and spindle. Precision ground to the industry standard AT3 tolerance, these chucks maintain a secure fit that minimizes runout in your machine spindle. They meet ASME standards for CAT spindles to ensure compatibility.
    While these chucks are designed for Big-Plus and other dual-contact CAT spindles, they can also be used in standard CAT spindles, just without the added rigidity of the dual contact.
    Internal threads on the shank let you attach a retention knob, so you can connect these chucks to your machine’s drawbar system. Insert your collet and tighten the nut to clamp your tool in place. They have a collet stop screw that sets the tool depth in the chuck for consistent, repeatable performance when you change tools. An RFID chip hole holds a small RFID tag for automatic tool identification and tracking. These chucks can deliver coolant to your tool’s cutting edge to clear chips and extend tool life. If you have a through-spindle coolant (TSC) machine, pair them with an ER coolant control collet for the best results.
    To maximize grip and minimize runout, choose a chuck where your bit diameter falls in the middle of the bit shank size range.
    Milling Machine Collet Chucks
    Wrenches
    Replacement Nuts
    For Collet
    Type
    For Bit Shank
    Size
    Projection
    Total Indicated Runout
    (TIR) Accuracy
    Material
    Collet Nut Type
    Coolant Delivery
    Type
    Features
    Specs.
    Met
    Each
    Each
    Each
    CAT 40 Machine Taper
     
    2.5 mm/s @ 25,000 rpm
    ER-250.039" to 0.629"4"0.0001"Hardened Nickel Chrome-Moly SteelBearing External Round NutThrough BoreCollet Stop Screw, RFID Chip HoleASME B5.509509N1300000009506N3300000009615N43000000
     
    CAT 50 Machine Taper
     
    2.5 mm/s @ 25,000 rpm
    ER-250.039" to 0.629"4"0.0001"Hardened Nickel Chrome-Moly SteelBearing External Round NutThrough BoreCollet Stop Screw, RFID Chip HoleASME B5.509509N160000009506N330000009615N4300000
     

    HSK Taper Collet Chucks

    Image of Product. Front orientation. Contains Annotated. Milling Machine Collet Chucks. HSK Taper Collet Chucks.
    Hold collets tightly in CNC machines with HSK taper spindles for milling, drilling, and routing. Made from high-grade nickel chrome-moly steel, these chucks remain rigid and accurate while resisting wear. They’re also precisely balanced for high speeds, which leads to longer tool life and better finishes on workpieces compared to less balanced chucks. They meet DIN and ISO standards for compatibility across machines with HSK spindles.
    These chucks have nuts with internal ball bearings for the smoothest and most uniform clamping. This results in a stronger grip, better accuracy, and less wear on your tool. Insert your collet and tighten the nut to clamp your tool in place. They have a collet stop screw that sets the tool depth in the chuck for consistent, repeatable performance when you change tools. An RFID chip hole holds a small RFID tag for automatic tool identification and tracking.
    To route coolant through these chucks without washing away the grease in your spindle, install HSK coolant tubes. If you have a machine that sends coolant through the spindle, pair them with an ER coolant control collet for the best results.
    To maximize grip and minimize runout, choose a chuck where your tool diameter falls in the middle of the bit shank size range.
    Milling Machine Collet Chucks
    Wrenches
    Replacement Nuts
    For Collet
    Type
    For Bit Shank
    Size
    Projection
    Total Indicated Runout
    (TIR) Accuracy
    Material
    Collet Nut Type
    Coolant Delivery
    Type
    Features
    Specs. Met
    Each
    Each
    Each
    HSK 63A Machine Taper
     
    2.5 mm/s @ 25,000 rpm
    ER-250.039" to 0.629"3"0.0001"Hardened Nickel Chrome-Moly SteelBearing Slotted NutThrough BoreCollet Stop Screw, RFID Chip HoleDIN 69893, ISO 121649511N1500000005699N1280000006163N114000000
    ER-250.039" to 0.629"5"0.0001"Hardened Nickel Chrome-Moly SteelBearing Slotted NutThrough BoreCollet Stop Screw, RFID Chip HoleDIN 69893, ISO 121649511N160000005699N128000006163N11400000
     
    HSK 100A Machine Taper
     
    2.5 mm/s @ 25,000 rpm
    ER-250.039" to 0.629"4"0.0001"Hardened Nickel Chrome-Moly SteelBearing Slotted NutThrough BoreCollet Stop Screw, RFID Chip HoleDIN 69893, ISO 121649511N250000005699N128000006163N11400000
    ER-250.039" to 0.629"6"0.0001"Hardened Nickel Chrome-Moly SteelBearing Slotted NutThrough BoreCollet Stop Screw, RFID Chip HoleDIN 69893, ISO 121649511N260000005699N128000006163N11400000
     

    ER Collet Nuts

    Image of System. Side1 orientation. Contains Annotated. Collet Nuts. ER Collet Nuts.
    Image of Product. Collet Nut with Slotted Drive. Front orientation. Collet Nuts. ER Collet Nuts.
    Image of Product. Ultra-Low-Friction Bearing Collet Nut with Slotted Drive. Front orientation. Collet Nuts. ER Collet Nuts.
    Image of Product. Miniature Collet Nut. Front orientation. Collet Nuts. ER Collet Nuts.
    Image of Product. Collet Nut with Hex Drive. Front orientation. Collet Nuts. ER Collet Nuts.
    Image of Product. Ultra-Low-Friction Bearing Collet Nut with External Round Drive. Front orientation. Collet Nuts. ER Collet Nuts.

    Collet Nut with

    Slotted Drive

    Ultra-Low-Friction

    Bearing Collet Nut

    with Slotted Drive

    Miniature

    Collet Nut

    Collet Nut with Hex

    Drive

    Ultra-Low-Friction

    Bearing Collet Nut

    with External

    Round Drive

    Secure ER collets inside collet chucks and fixtures. Tightening these nuts squeezes the collet around the cutting tool to clamp it firmly in place.
    Low Friction—Low-friction coated nuts tighten more smoothly than standard collet nuts for even clamping and longer tool life. Replace them when the coating wears away.
    Ultra Low Friction—Ultra-low-friction bearing nuts are often used in the highest quality chucks. Instead of a coating that can wear away, these nuts have internal ball bearings for the smoothest and most uniform clamping. The result is a stronger grip, higher accuracy, and longer tool life compared to coated collet nuts. You can take them apart and clean them rather than replacing them.
    External Round Drive—External round nuts don’t have slots that trap coolant or chips. They spin with less resistance than other nuts and excel in high-speed machining operations. Also known as smooth collet nuts.
    Nuts
    Wrenches
    Drive
    For Collet
    Type
    Thread Size
    Style
    Size,
    mm
    Max. Rotation
    Speed, rpm
    Dia.,
    mm
    Ht.,
    mm
    Recommended Tightening
    Torque, ft·lbf
    Material
    Specs. Met
    Each
    Each
    Collet Nuts
    ER-25M32 × 1.5 mmSlotted
    3625,000422260Hardened SteelISO 15488 Form B9615N180000005699N128000000
     
    Low-Friction Coated Collet Nuts
    ER-25M32 × 1.5 mmSlotted
    35.725,000422177Hardened SteelISO 15488 Form B9615N35000005699N12800000
     
    Ultra-Low-Friction Bearing Collet Nuts
    ER-25M32 × 1.5 mmExternal Round4225,000422073Hardened Nickel Chrome-Moly SteelISO 15488 Form B9615N43000009506N33000000
    ER-25M32 × 1.5 mmSlotted
    3725,000422073Hardened Nickel Chrome-Moly SteelISO 15488 Form B6163N114000005699N12800000
     
    Miniature Collet Nuts
    ER-25M30 × 1 mmSlotted
    29.525,000352028Hardened Steel9615N1500000———0
     
    Miniature Low-Friction Coated Collet Nuts
    ER-25M30 × 1 mmSlotted
    28.625,000352128Hardened SteelISO 15488 Form B9615N2800000———0
     
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