McMaster-Carr logo
    Enter e-mail addresses in the fields below
    Message
    Cancel
    Comments
    E-mail address (if you would like a response)
    54 Products

    Step-Down Shaft Adapters

    Image of Product. Front orientation. Shaft Adapters. Step-Down Shaft Adapters, For Keyed Shafts.
    Image of Product. Front orientation. Shaft Adapters. Step-Down Shaft Adapters, For Round Shafts.

    For Keyed Shafts

    For Round Shafts

    Image of Attribute. Front orientation. Contains Annotated. Step-Down Shaft Adapters.
    Reduce the diameter of your shaft while adding length. One side of the adapter is a two-piece coupling that clamps onto your existing shaft; a smaller shaft extends from the other side. Tighten the clamping screws for a firm, even grip that won’t damage shafts.
    Black Oxide Steel—Black-oxide steel adapters have a finish that adds a layer of rust resistance but should be used in primarily dry environments. Because they’re steel, they balance high strength and good machinability, making them ideal for general purpose use.
    303 Stainless Steel—303 stainless steel adapters resist corrosion in damp environments. They are easier to machine than other types of stainless steel but more difficult to machine than steel.
    For Shaft
    Dia.
    Shaft
    Dia.
    Overall
    Lg.
    Shaft
    Lg.
    Bore
    Dp.
    OD
    Max. Rotation
    Speed
    Max.
    Torque
    Each
    Black Oxide Steel
     
    For Keyed Shafts
    3/4"1/2"3 1/2"1 1/4"1 5/8"1 3/4"Not RatedNot Rated9783T11000000
    7/8"5/8"3 5/8"1 1/4"1 7/8"1 7/8"Not RatedNot Rated9783T1200000
    1"3/4"3 5/8"1 1/4"2"2"Not RatedNot Rated9783T1300000
    1 1/8"7/8"3 7/8"1 1/2"2"2 1/8"Not RatedNot Rated9783T1400000
    1 1/4"1"4 1/2"2"2"2 1/4"Not RatedNot Rated9783T1500000
    1 3/8"1 1/8"5"2"2 1/4"2 3/8"Not RatedNot Rated9783T1600000
    1 1/2"1 1/4"5 3/8"2 3/8"2 1/4"2 1/2"Not RatedNot Rated9783T1700000
     
    For Round Shafts
    3/8"1/4"2 1/8"13/16"1 1/8"1 1/16"Not RatedNot Rated9783T1900000
    1/2"3/8"2 5/8"1 1/8"1 1/4"1 1/4"Not RatedNot Rated9783T1800000
    3/4"1/2"3 1/2"1 1/4"1 5/8"1 3/4"Not RatedNot Rated9783T100000
    7/8"5/8"3 5/8"1 1/4"1 7/8"1 7/8"Not RatedNot Rated9783T200000
    1"3/4"3 5/8"1 1/4"2"2"Not RatedNot Rated9783T300000
    1 1/8"7/8"3 7/8"1 1/2"2"2 1/8"Not RatedNot Rated9783T400000
    1 1/4"1"4 1/2"2"2"2 1/4"Not RatedNot Rated9783T500000
    1 3/8"1 1/8"5"2"2 1/4"2 3/8"Not RatedNot Rated9783T600000
    1 1/2"1 1/4"5 3/8"2 3/8"2 1/4"2 1/2"Not RatedNot Rated9783T700000
     
    303 Stainless Steel
     
    For Keyed Shafts
    3/4"1/2"3 1/2"1 1/4"1 5/8"1 3/4"Not RatedNot Rated9783T34000000
    7/8"5/8"3 5/8"1 1/4"1 7/8"1 7/8"Not RatedNot Rated9783T35000000
    1"3/4"3 5/8"1 1/4"2"2"Not RatedNot Rated9783T36000000
    1 1/4"1"4 1/2"2"2"2 1/4"Not RatedNot Rated9783T37000000
     
    For Round Shafts
    3/4"1/2"3 1/2"1 1/4"1 5/8"1 3/4"Not RatedNot Rated9783T3100000
    7/8"5/8"3 5/8"1 1/4"1 7/8"1 7/8"Not RatedNot Rated9783T3200000
    1"3/4"3 5/8"1 1/4"2"2"Not RatedNot Rated9783T33000000
     

    Step-Up Shaft Adapters

    Image of Product. Front orientation. Shaft Adapters. Step-Up Shaft Adapters, For Keyed Shafts.

    For Keyed Shafts

    Image of Product. Front orientation. Shaft Adapters. Step-Up Shaft Adapters, For Round Shafts.

    For Round Shafts

    Image of Attribute. Front orientation. Contains Annotated. Step-Up Shaft Adapters.
    Increase the diameter of your shaft while also making it longer. One side of these adapters clamp onto your shaft; the other side becomes your new larger end so you don’t have to replace the entire shaft. Tighten the clamping screws for a firm, even grip that won’t damage shafts.
    Black Oxide Steel—Black-oxide steel adapters have a finish that adds a layer of rust resistance but should be used in primarily dry environments. Because they’re steel, they balance high strength and good machinability, making them ideal for general purpose use.
    303 Stainless Steel—303 stainless steel adapters resist corrosion in damp environments. They are easier to machine than other types of stainless steel but more difficult to machine than steel.
    For Shaft
    Dia.
    Shaft
    Dia.
    Overall
    Lg.
    Shaft
    Lg.
    Bore
    Dp.
    OD
    Max. Rotation
    Speed
    Max.
    Torque
    Each
    Black Oxide Steel
     
    For Keyed Shafts
    1/2"3/4"2 3/4"1 1/4"1 1/4"1 1/4"Not RatedNot Rated3256K210000000
    5/8"7/8"3 1/4"1 1/2"1 3/8"1 1/2"Not RatedNot Rated3256K22000000
    3/4"1"4 1/4"2 3/8"1 5/8"1 3/4"Not RatedNot Rated3256K23000000
    7/8"1 1/8"4 3/8"2"1 7/8"2"Not RatedNot Rated3256K24000000
    1"1 1/4"4 3/4"2 3/8"2"2"Not RatedNot Rated3256K25000000
    1 1/8"1 3/8"4 3/4"2 3/8"2"2 1/8"Not RatedNot Rated3256K26000000
    1 1/4"1 1/2"5"2 1/2"2"2 1/4"Not RatedNot Rated3256K27000000
     
    For Round Shafts
    1/4"3/8"1 7/8"7/8"13/16"13/16"Not RatedNot Rated3256K1900000
    3/8"1/2"2 1/2"1 1/8"1 1/8"1 1/16"Not RatedNot Rated3256K1800000
    1/2"3/4"2 3/4"1 1/4"1 1/4"1 1/4"Not RatedNot Rated3256K1100000
    5/8"7/8"3 1/4"1 1/2"1 3/8"1 1/2"Not RatedNot Rated3256K1200000
    3/4"1"4 1/4"2"1 5/8"1 3/4"Not RatedNot Rated3256K1300000
    7/8"1 1/8"4 3/8"2"1 7/8"1 7/8"Not RatedNot Rated3256K1400000
    1"1 1/4"4 3/4"2 3/8"2"2"Not RatedNot Rated3256K1500000
    1 1/8"1 3/8"4 3/4"2 3/8"2"2 1/8"Not RatedNot Rated3256K1600000
    1 1/4"1 1/2"5"2 1/2"2"2 1/4"Not RatedNot Rated3256K1700000
     
    303 Stainless Steel
     
    For Keyed Shafts
    1/2"3/4"2 3/4"1 1/4"1 1/4"1 1/4"Not RatedNot Rated3256K44000000
    5/8"7/8"3 1/4"1 1/2"1 3/8"1 1/2"Not RatedNot Rated3256K45000000
    3/4"1"4 1/4"2"1 5/8"1 3/4"Not RatedNot Rated3256K46000000
    1"1 1/4"4 3/4"2 3/8"2"2"Not RatedNot Rated3256K47000000
     
    For Round Shafts
    1/2"3/4"2 3/4"1 1/4"1 1/4"1 1/4"Not RatedNot Rated3256K4100000
    5/8"7/8"3 1/4"1 1/2"1 3/8"1 1/2"Not RatedNot Rated3256K4200000
    3/4"1"4 1/4"2"1 5/8"1 3/4"Not RatedNot Rated3256K43000000
     

    Threaded Shaft Adapters

    Image of Product. Front orientation. Shaft Adapters. Threaded Shaft Adapters, For Keyed Shafts.

    For Keyed Shafts

    Image of Product. Front orientation. Shaft Adapters. Threaded Shaft Adapters, For Round Shafts.

    For Round Shafts

    Image of Attribute. Side1 orientation. Contains Annotated. Threaded Shaft Adapters.
    Adapt your shaft to a threaded end without having to machine threads onto your shaft. These adapters have a threaded end that mounts into tapped holes or can be used for threaded accessories, such as mixer propellers or fan blades. To attach these adapters to your existing shaft, tighten the clamping screws for a firm, even grip that won’t damage shafts. Made of steel, these adapters balance high strength and good machinability, making them ideal for general purpose use. They have a black-oxide finish that resists rust but should be used in primarily dry environments.
    Thread
    For Shaft
    Dia.
    Size
    Lg.
    Overall
    Lg.
    Bore
    Dp.
    OD
    Max. Rotation
    Speed
    Max.
    Torque
    Each
    Black Oxide Steel
     
    For Keyed Shafts
    1/2"1/2"-13
    1"2 3/4"1 1/4"1 1/4"Not RatedNot Rated4244N110000000
    5/8"5/8"-11
    1 1/4"3 1/4"1 1/2"1 1/2"Not RatedNot Rated4244N12000000
    3/4"3/4"-10
    1 1/2"4 1/4"1 5/8"1 3/4"Not RatedNot Rated4244N13000000
    1"1"-8
    2"4 3/4"2"2"Not RatedNot Rated4244N14000000
     
    For Round Shafts
    1/2"1/2"-13
    1"2 3/4"1 1/4"1 1/4"Not RatedNot Rated4244N15000000
    5/8"5/8"-11
    1 1/4"3 1/4"1 1/2"1 1/2"Not RatedNot Rated4244N16000000
    3/4"3/4"-10
    1 1/2"4 1/4"1 5/8"1 3/4"Not RatedNot Rated4244N17000000
    1"1"-8
    2"4 3/4"2"2"Not RatedNot Rated4244N18000000
     
    back to top