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    10 Products

    ER Collets

    Image of System. Side1 orientation. CrossSection view. Contains Annotated. Milling Machine Collets. ER Collets.
    Image of Product. Front orientation. Milling Machine Collets. ER Collets.
    The most widely used type of collet, these collets hold cutting tools in ER collet chucks for milling, drilling, and routing. Spring slots clamp evenly around the shank to minimize runout for clean, accurate cuts and long tool life. The slots flex to grip slightly undersized shanks too, so you don't need an exact match for each cutting tool in your lineup. You can also use these collets in ER collet fixtures and custom setups to keep small round parts centered.
    52100 Alloy Steel—Hardened 52100 alloy steel collets are made from the same tough material used to make bearings. They’re more wear-resistant than basic spring steel collets but will wear faster than hardened chrome-moly steel collets if you change bits frequently.
    Chrome-Moly Steel—Hardened chrome-moly steel collets are more wear-resistant than hardened 52100 alloy steel collets. They hold their shape better over time and have lower runout, even with frequent bit changes. Often used for high-volume production runs, they stand up to high-speed, high-force machining in any material.
    Collet
    Size
    Grip Range
    Total Indicated Runout
    (TIR) Accuracy
    ID Tolerance
    Max. Body
    Dia.
    Overall
    Lg.
    Specs. Met
    Each
    ER-16
     
    Hardened Chrome-Moly Steel
    13/32"0.367" to 0.406"0.0002"-0.0001" to 0.0001"0.68"1.06"DIN 6499-B, ISO 15488 Form B3215A314000000
     
    ER-20
     
    Hardened Chrome-Moly Steel
    13/32"0.367" to 0.406"0.0002"-0.0001" to 0.0001"0.83"1.22"DIN 6499-B, ISO 15488 Form B1724N2300000
     
    ER-25
     
    Hardened 52100 Alloy Steel
    13/32"0.367" to 0.406"0.0002"-0.0004" to 0"1.02"1.34"DIN 6499-B, ISO 15488 Form B3669N11300000
     
    Hardened Chrome-Moly Steel
    13/32"0.367" to 0.406"0.0002"-0.0001" to 0.0001"1.03"1.38"DIN 6499-B, ISO 15488 Form B3669N2300000
     
    ER-32
     
    Hardened 52100 Alloy Steel
    13/32"0.367" to 0.406"0.0002"-0.0004" to 0"1.3"1.57"DIN 6499-B, ISO 15488 Form B3321A31300000
     
    Hardened Chrome-Moly Steel
    13/32"0.367" to 0.406"0.0002"-0.0001" to 0.0001"1.3"1.57"DIN 6499-B, ISO 15488 Form B3321A11400000
     

    R8 Collets

    Image of Product. Front orientation. Milling Machine Collets. R8 Collets.
    Grip cutting tools in the R8 taper spindle of your Bridgeport or other milling machine. These collets thread onto your machine’s drawbar, pulling them into the spindle so they can clamp tightly around your bit.
    The lower the runout, the higher the accuracy and the longer the tool life.
    0.0008" Total Indicated Runout (TIR) Accuracy—An accuracy of 0.0008” works well for roughing and heavy material removal, where tight tolerances aren't critical.
    Collet
    Size
    ID Tolerance
    Body
    Dia.
    Overall
    Lg.
    Internal
    Thread Size
    Each
    Hardened Steel—0.0002" Total Indicated Runout (TIR) Accuracy
    13/32"-0.004" to 0"0.95"4.089"7/16"-20
    		3257A21000000
     
    Hardened Steel—0.0008" Total Indicated Runout (TIR) Accuracy
    13/32"0" to 0.001"0.95"4.134"7/16"-20
    		3257A31300000
     

    5C Lathe Collets

    Image of Product. Front orientation. Contains Inset. Lathe Collets. 5C Lathe Collets, Round Face.

    Round Face

    These collets tightly grip workpieces when installed into a 5C collet chuck or holder. They provide a stronger hold on small workpieces than a standard lathe chuck.
    Collet
    Size
    Total Indicated Runout
    (TIR) Accuracy
    Workpiece Dia.
    Tolerance
    Body
    Dia.
    Overall
    Lg.
    Internal Thread
    Size
    External Thread
    Size
    Material
    Each
    Round Face
    13/32"0.0011"-0.004" to 0"1 1/4"3.27"1.041"-241.238"-20Steel
    		3223A435000000
     

    ER Coolant Control Collets

    Image of System. Side1 orientation. CrossSection view. Contains Annotated. Milling Machine Collets. ER Coolant Control Collets.
    Image of ProductInUse. Sealed Shown in Use. Front orientation. Milling Machine Collets. ER Coolant Control Collets, Sealed Coolant Delivery Collet.
    Image of Product. Sealed. Front orientation. Milling Machine Collets. ER Coolant Control Collets, Sealed Coolant Delivery Collet.

    Sealed

    Shown in Use

    Sealed

    Made with high-performance machining in mind—these collets not only grip your cutting tool but also direct coolant to the tool's cutting edge. They have coolant channels designed to work with through-spindle coolant (TSC) systems to clear chips and reduce heat from friction, resulting in clean cuts and long tool life. Place them directly into your ER collet holder, no need to fuss with special collet nuts, coolant rings, or repositioning hoses and nozzles with every setup change.
    You get the benefits of using an ER collet, too. Spring slots clamp evenly around the shank to minimize runout for accurate cuts. Keep in mind, these collets must form a tight seal around the tool shank for proper coolant delivery, so match the shank size to the collet size exactly for the best results.
    Sealed Coolant Delivery Collet—Sealed collets run coolant through the cutting tool, so they only work with tools that have coolant holes. Since the coolant runs through the tool, they’re a better choice for deep-hole drilling and high-speed machining than collets with angled ports. Steel seals are built into their body, so they withstand higher pressure and last longer than collets with rubber seals.
    Chrome-Moly Steel—Hardened chrome-moly steel collets are more wear-resistant than hardened 52100 alloy steel collets. They hold their shape better over time and have lower runout, even with frequent bit changes. Often used for high-volume production runs, they stand up to high-speed, high-force machining in any material. Their maximum coolant pressure is higher than 52100 alloy steel collets, so they’re a better choice for deep-hole drilling and turning operations in CNC Swiss lathes.
    Collet
    Size
    Grip Range
    Total Indicated Runout
    (TIR) Accuracy
    ID Tolerance
    Max. Coolant
    Pressure, psi
    Max. Body
    Dia.
    Overall
    Lg.
    Specs. Met
    Each
    ER-32—Sealed
     
    Hardened Chrome-Moly Steel
    13/32"0.387" to 0.406"0.0002"-0.0001" to 0.0001"2,9001.3"1.57"DIN 6499-B, ISO 15488 Form B3321A158000000
     
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