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    53 Products

    Rounded Machine Keys

    Image of Product. Front orientation. Machine Keys. Rounded Machine Keys.
    When installed, these keys fill oval keyways completely, reducing stress on the key and shaft. Using them in a closed keyway keeps them from sliding along the shaft axis. The rounded ends make it easy to slide gears, hubs, and other components into place. These are also known as feather keys. Machine keys are often the same material as the shaft and other components with which they are used. To use a key as a sacrificial part, choose a softer key that will shear off when parts are exposed to excessive force, preventing damage to expensive equipment.
    1008-1045 Carbon Steel—Steel keys are strong and easy to machine. Since steel is the most common material, these keys work in many applications. Steel keys rust when exposed to moisture, so they should only be used in dry environments.
    Zinc-Plated 1008-1045 Carbon Steel— Zinc-plated steel keys resist corrosion in wet environments.
    Oversized Tolerance—Slightly larger than the size listed in the table, oversized keys fit tightly in a keyway. Press them into place for use in high-torque applications or to replace a key in a worn keyway.
    ASME B17.1 Class 2—Keys that meet ASME B17.1 specifications conform to ASME standards for dimensions and tolerances.
    Tolerance
    Lg.
    Tolerance
    Rating
    Ht.
    Wd.
    Min.
    Hardness
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    1008-1045 Carbon Steel
     
    1/8" × 1/8"
    1/2"Oversized0.000" to 0.001"0.000" to 0.001"Not RatedASME B17.1 Class 2500000000000000
    3/4"Oversized0.000" to 0.001"0.000" to 0.001"Not RatedASME B17.1 Class 250000000000000
    1"Oversized0.000" to 0.001"0.000" to 0.001"Not RatedASME B17.1 Class 250000000000000
     
    3/16" × 3/16"
    1"Oversized0.000" to 0.001"0.000" to 0.001"Not RatedASME B17.1 Class 250000000000000
    1 1/4"Oversized0.000" to 0.001"0.000" to 0.001"Not RatedASME B17.1 Class 250000000000000
    2"Oversized0.000" to 0.001"0.000" to 0.001"Not RatedASME B17.1 Class 250000000000000
     
    1/4" × 1/4"
    3/4"Oversized0.000" to 0.001"0.000" to 0.001"Not RatedASME B17.1 Class 250000000000000
    1"Oversized0.000" to 0.001"0.000" to 0.001"Not RatedASME B17.1 Class 250000000000000
    1 1/4"Oversized0.000" to 0.001"0.000" to 0.001"Not RatedASME B17.1 Class 250000000000000
    1 1/2"Oversized0.000" to 0.001"0.000" to 0.001"Not RatedASME B17.1 Class 250000000000000
    1 3/4"Oversized0.000" to 0.001"0.000" to 0.001"Not RatedASME B17.1 Class 250000000000000
    2"Oversized0.000" to 0.001"0.000" to 0.001"Not RatedASME B17.1 Class 250000000000000
    2 1/2"Oversized0.000" to 0.001"0.000" to 0.001"Not RatedASME B17.1 Class 250000000000000
     
    1/2" × 1/2"
    1 1/2"Oversized0.000" to 0.001"0.000" to 0.001"Not RatedASME B17.1 Class 210000000000000
    1 5/8"Oversized0.000" to 0.001"0.000" to 0.001"Not RatedASME B17.1 Class 210000000000000
    2 1/2"Oversized0.000" to 0.001"0.000" to 0.001"Not RatedASME B17.1 Class 210000000000000
     
    Zinc-Plated 1008-1045 Carbon Steel
     
    1/8" × 1/8"
    1/2"Oversized0.000" to 0.001"0.000" to 0.001"Not RatedASME B17.1 Class 2500000000000000
    1"Oversized0.000" to 0.001"0.000" to 0.001"Not RatedASME B17.1 Class 2500000000000000
     
    3/16" × 3/16"
    1/2"Oversized0.000" to 0.002"0.000" to 0.002"Rockwell B50ASME B17.1 Class 250000000000000
    3/4"Oversized0.000" to 0.002"0.000" to 0.002"Rockwell B50ASME B17.1 Class 250000000000000
    1"Oversized0.000" to 0.001"0.000" to 0.001"Not RatedASME B17.1 Class 2500000000000000
     
    1/4" × 1/4"
    1"Oversized0.000" to 0.001"0.000" to 0.001"Not RatedASME B17.1 Class 2500000000000000
    1 1/2"Oversized0.000" to 0.001"0.000" to 0.001"Not RatedASME B17.1 Class 2500000000000000
     

    Tapped Rounded Machine Keys

    Image of Product. Front orientation. Machine Keys. Tapped Rounded Machine Keys.
    Thread a screw through the tapped hole to pop these keys out of a keyway. When installed, they fill oval keyways completely, reducing stress on the key and shaft. Using them in a closed keyway keeps them from sliding along the shaft axis. The rounded ends make it easy to slide gears, hubs, and other components into place. To install, press them in to place. Use them for permanent or high-torque applications, or to replace a key in a worn keyway. Keys are made of steel.
    Oversized Tolerance—Oversized keys create a tight fit. They conform to ASME B17.1 Class 2 standards for dimensions and tolerances.
    Tolerance
    Lg.
    Tolerance
    Rating
    Ht.
    Wd.
    Min.
    Hardness
    Thread
    Size
    Specs. Met
    Each
    1018-1045 Carbon Steel
     
    3/16" × 3/16"
    1/2"Oversized0.000" to 0.001"0.000" to 0.001"Not Rated4-40
    ASME B17.1 Class 200000000000000
    3/4"Oversized0.000" to 0.001"0.000" to 0.001"Not Rated4-40
    ASME B17.1 Class 20000000000000
    1"Oversized0.000" to 0.001"0.000" to 0.001"Not Rated4-40
    ASME B17.1 Class 20000000000000
    1 1/2"Oversized0.000" to 0.001"0.000" to 0.001"Not Rated4-40
    ASME B17.1 Class 20000000000000
    1 3/4"Oversized0.000" to 0.001"0.000" to 0.001"Not Rated4-40
    ASME B17.1 Class 20000000000000
    2"Oversized0.000" to 0.001"0.000" to 0.001"Not Rated4-40
    ASME B17.1 Class 20000000000000
     
    1/4" × 1/4"
    3/4"Oversized0.000" to 0.001"0.000" to 0.001"Not Rated6-32
    ASME B17.1 Class 20000000000000
    1"Oversized0.000" to 0.001"0.000" to 0.001"Not Rated6-32
    ASME B17.1 Class 20000000000000
    1 1/4"Oversized0.000" to 0.001"0.000" to 0.001"Not Rated6-32
    ASME B17.1 Class 20000000000000
    1 1/2"Oversized0.000" to 0.001"0.000" to 0.001"Not Rated6-32
    ASME B17.1 Class 20000000000000
    1 3/4"Oversized0.000" to 0.001"0.000" to 0.001"Not Rated6-32
    ASME B17.1 Class 20000000000000
    2"Oversized0.000" to 0.001"0.000" to 0.001"Not Rated6-32
    ASME B17.1 Class 20000000000000
    2 1/2"Oversized0.000" to 0.001"0.000" to 0.001"Not Rated6-32
    ASME B17.1 Class 20000000000000
     
    3/8" × 3/8"
    1 1/2"Oversized0.000" to 0.001"0.000" to 0.001"Not Rated10-24
    ASME B17.1 Class 20000000000000
    2"Oversized0.000" to 0.001"0.000" to 0.001"Not Rated10-24
    ASME B17.1 Class 20000000000000
     
    1/2" × 1/2"
    2"Oversized0.000" to 0.001"0.000" to 0.001"Not Rated1/4"-20
    ASME B17.1 Class 20000000000000
     

    Machine Keys

    Image of Product. Front orientation. Machine Keys. Machine Keys.
    Straight keys, with a square or rectangular cross section, are the most common type of key. Install them in keyways to transmit torque from shafts to gears and other components. Machine keys are often the same material as the shaft and other components with which they are used. To use a key as a sacrificial part, choose a softer key that will shear off when parts are exposed to excessive force, preventing damage to expensive equipment.
    1008-1045 Carbon Steel—Steel keys are strong and easy to machine. Since steel is the most common material, these keys work in many applications. Steel keys rust when exposed to moisture, so they should only be used in dry environments.
    Zinc-Plated 1008-1045 Carbon Steel— Zinc-plated steel keys resist corrosion in wet environments.
    Oversized Tolerance—Slightly larger than the size listed in the table, oversized keys fit tightly in a keyway. Press them into place for use in high-torque applications or to replace a key in a worn keyway.
    ASME B17.1 Class 2—Keys that meet ASME B17.1 specifications conform to ASME standards for dimensions and tolerances.
    Tolerance
    Lg.
    Tolerance
    Rating
    Ht.
    Wd.
    Min.
    Hardness
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    1008-1045 Carbon Steel
     
    3/16" × 3/16"
    1 3/8"Oversized0.000" to 0.001"0.000" to 0.001"Not RatedASME B17.1 Class 2500000000000000
     
    1/4" × 1/4"
    3"Oversized0.000" to 0.001"0.000" to 0.001"Not RatedASME B17.1 Class 250000000000000
    5"Oversized0.000" to 0.001"0.000" to 0.001"Not RatedASME B17.1 Class 250000000000000
     
    5/16" × 5/16"
    1 1/4"Oversized0.000" to 0.001"0.000" to 0.001"Not RatedASME B17.1 Class 250000000000000
     
    3/8" × 3/8"
    1 1/2"Oversized0.000" to 0.001"0.000" to 0.001"Not RatedASME B17.1 Class 250000000000000
    2 1/2"Oversized0.000" to 0.001"0.000" to 0.001"Not RatedASME B17.1 Class 250000000000000
     
    1/2" × 1/2"
    2 1/2"Oversized0.000" to 0.001"0.000" to 0.001"Not RatedASME B17.1 Class 2500000000000000
     
    Zinc-Plated 1008-1045 Carbon Steel
     
    3/16" × 3/16"
    1 3/8"Oversized0.000" to 0.002"0.000" to 0.002"Rockwell B50ASME B17.1 Class 210000000000000
     

    Machine Key Stock

    Cut this square or rectangular key stock to length to create a straight machine key. Straight keys are the most common type of key. Machine keys are often the same material as the shaft and other components with which they are used. To use a key as a sacrificial part, choose a softer key that will shear off when parts are exposed to excessive force, preventing damage to expensive equipment.
    8630 Alloy Steel
    Image of Product. Front orientation. Machine Key Stock. Machine Key Stock.
    8630 alloy steel key stock is an economical choice with good strength.
    Oversized Tolerance—Slightly larger than the size listed in the table, oversized stock fits tightly in a keyway. Press it into place for use in high-torque applications or to replace a key in a worn keyway.
    ASME B17.1 Class 2—Key stock that meets ASME B17.1 Class 2 specifications conforms to ASME standards for dimensions and tolerances.
    Tolerance
    Ht. × Wd.
    Tolerance
    Rating
    Ht.
    Wd.
    Min.
    Hardness
    Specs. Met
    Each
    12" Long
    1/8" × 1/8"Oversized0.000" to 0.001"0.000" to 0.001"Rockwell B50ASME B17.1 Class 200000000000000
    3/16" × 3/16"Oversized0.000" to 0.001"0.000" to 0.001"Rockwell B50ASME B17.1 Class 20000000000000
    1/4" × 1/4"Oversized0.000" to 0.001"0.000" to 0.001"Rockwell B50ASME B17.1 Class 20000000000000
    5/16" × 5/16"Oversized0.000" to 0.001"0.000" to 0.001"Rockwell B50ASME B17.1 Class 20000000000000
    3/8" × 3/8"Oversized0.000" to 0.001"0.000" to 0.001"Rockwell B50ASME B17.1 Class 20000000000000
    1/2" × 1/2"Oversized0.000" to 0.001"0.000" to 0.001"Rockwell B50ASME B17.1 Class 20000000000000
     
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