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    5 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-25
     
    Hardened Chrome-Moly Steel
    17/32"0.492" to 0.531"0.0002"-0.0001" to 0.0001"1.03"1.38"DIN 6499-B, ISO 15488 Form B3669N27000000
     
    ER-32
     
    Hardened Chrome-Moly Steel
    17/32"0.492" to 0.531"0.0002"-0.0001" to 0.0001"1.3"1.57"DIN 6499-B, ISO 15488 Form B3321A11600000
     
    ER-40
     
    Hardened 52100 Alloy Steel
    17/32"0.492" to 0.531"0.0002"-0.0004" to 0"1.61"1.81"DIN 6499-B, ISO 15488 Form B9498N2300000
     

    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.
    Collet
    Size
    ID Tolerance
    Body
    Dia.
    Overall
    Lg.
    Internal
    Thread Size
    Each
    Hardened Steel—0.0002" Total Indicated Runout (TIR) Accuracy
    17/32"-0.004" to 0"0.95"4.089"7/16"-20
    		3257A25000000
     

    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
    17/32"0.0011"-0.004" to 0"1 1/4"3.27"1.041"-241.238"-20Steel
    		3223A444000000
     
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