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    66 Products

    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.
    18-8 Stainless Steel—18-8 stainless steel keys offer a balance of strength and corrosion resistance. They may be mildly magnetic.
    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.
    Undersized Tolerance—Slightly smaller than the size listed in the table, undersized keys are the choice when you need a slightly looser fit or when you have an inconsistent keyway. Use them when parts need to be taken apart frequently, such as for maintenance or prototyping.
    ASME B17.1 Class 1—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"
    1/4"Undersized-0.002" to 0.000"-0.002" to 0.000"Rockwell B50ASME B17.1 Class 11098870A090000000
    1/2"Oversized0.000" to 0.002"0.000" to 0.002"Rockwell B50—1098870A3050000
    1/2"Undersized-0.002" to 0.000"-0.002" to 0.000"Rockwell B50ASME B17.1 Class 11098870A0950000
    3/4"Oversized0.000" to 0.002"0.000" to 0.002"Rockwell B50—1098870A31000000
    3/4"Undersized-0.002" to 0.000"-0.002" to 0.000"Rockwell B50ASME B17.1 Class 11098870A1000000
    1"Oversized0.000" to 0.002"0.000" to 0.002"Rockwell B50—1098870A3150000
    1"Undersized-0.002" to 0.000"-0.002" to 0.000"Rockwell B50ASME B17.1 Class 11098870A1100000
    1 1/4"Undersized-0.002" to 0.000"-0.002" to 0.000"Rockwell B50ASME B17.1 Class 11098870A1150000
    1 1/2"Undersized-0.002" to 0.000"-0.002" to 0.000"Rockwell B50ASME B17.1 Class 11098870A1170000
     
    18-8 Stainless Steel
     
    1/8" × 1/8"
    1/4"Undersized-0.002" to 0.000"-0.002" to 0.000"Rockwell B82—1092624A0900000
    1/2"Oversized0.000" to 0.003"0.000" to 0.003"Rockwell B82—1092624A4050000
    1/2"Undersized-0.002" to 0.000"-0.002" to 0.000"Rockwell B82—1092624A0950000
    3/4"Undersized-0.002" to 0.000"-0.002" to 0.000"Rockwell B82—1092624A1000000
    1"Undersized-0.002" to 0.000"-0.002" to 0.000"Rockwell B82—1092624A1100000
    1 1/4"Undersized-0.002" to 0.000"-0.002" to 0.000"Rockwell B82—1092624A11500000
    1 1/2"Undersized-0.002" to 0.000"-0.002" to 0.000"Rockwell B82—1092624A11700000
     

    Woodruff Keys

    Image of Product. Front orientation. Contains Annotated. Machine Keys. Woodruff Keys.
    Image of Attribute. Side View. Front orientation. Contains Annotated. Woodruff Keys.

    Side View

    Woodruff keys work well near shaft shoulders, where a standard open keyway would create too much stress. They are also often used on tapered shafts. These keys have a rounded shape that makes them easy to remove when parts need to be taken apart frequently, such as for maintenance or prototyping. Because they're usually shorter than standard machine keys, they work best in light duty applications. Use them to connect gears and other components to shafts. Also known as half moon keys.
    1018-1045 Carbon Steel and 8630 Alloy Steel—Steel keys offer good strength.
    316 Stainless Steel—316 stainless steel keys have excellent corrosion resistance, but aren't as strong as steel keys. They may be mildly magnetic.
    Inch—Inch keys conform to ASME B17.2 standards for dimensions and tolerances.
    Tolerance
    Woodruff
    Key No.
    Wd.
    For Keyway
    Dia.
    Ht.
    Lg.
    Wd.
    Ht.
    Specs.
    Met
    System of
    Measurement
    Pkg.
    Qty.
    Pkg.
    1018-1045 Carbon Steel
    31/8"1/2"0.194"0.491"0.000" to 0.001"-0.006" to 0.000"ASME B17.2Inch10098481A090000000
    51/8"5/8"0.24"0.612"0.000" to 0.001"-0.006" to 0.000"ASME B17.2Inch10098481A10000000
    71/8"3/4"0.303"0.74"0.000" to 0.001"-0.006" to 0.000"ASME B17.2Inch10098481A11500000
    2131/8"3/8"0.172"0.374"0.000" to 0.001"-0.005" to 0.000"ASME B17.2Inch5098481A07500000
     
    8630 Alloy Steel
    31/8"1/2"0.194"0.491"0.000" to 0.001"-0.006" to 0.000"ASME B17.2Inch10098525A09000000
    51/8"5/8"0.24"0.612"0.000" to 0.001"-0.006" to 0.000"ASME B17.2Inch10098525A10000000
    71/8"3/4"0.303"0.74"0.000" to 0.001"-0.006" to 0.000"ASME B17.2Inch5098525A11500000
    2131/8"3/8"0.172"0.374"0.000" to 0.001"-0.005" to 0.000"ASME B17.2Inch5098525A07500000
     
    316 Stainless Steel
    31/8"1/2"0.194"0.491"0.000" to 0.001"-0.006" to 0.000"ASME B17.2Inch597940A09000000
    51/8"5/8"0.25"0.612"0.000" to 0.001"-0.005" to 0.000"ASME B17.2Inch597940A10000000
    71/8"3/4"0.303"0.74"0.000" to 0.001"-0.006" to 0.000"ASME B17.2Inch197940A1150000
    2131/8"3/8"0.172"0.374"0.000" to 0.001"-0.005" to 0.000"ASME B17.2Inch597940A07500000
     

    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.
    Undersized Tolerance—Slightly smaller than the size listed in the table, undersized keys are the choice when you need a slightly looser fit or when you have an inconsistent keyway. Use them when parts need to be taken apart frequently, such as for maintenance or prototyping. Undersized metric keys meet DIN 6885 dimensional standards.
    ASME B17.1 Class 1 and 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 2598870A23200000
    1/2"Undersized-0.002" to 0.000"-0.002" to 0.000"Not RatedASME B17.1 Class 1598870A6770000
    3/4"Oversized0.000" to 0.001"0.000" to 0.001"Not RatedASME B17.1 Class 2598870A3330000
    3/4"Undersized-0.002" to 0.000"-0.002" to 0.000"Not RatedASME B17.1 Class 1598870A9750000
    1"Oversized0.000" to 0.001"0.000" to 0.001"Not RatedASME B17.1 Class 2598870A3370000
    1"Undersized-0.002" to 0.000"-0.002" to 0.000"Not RatedASME B17.1 Class 1598870A6640000
     
    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 2595053A37900000
    1/2"Undersized-0.002" to 0.000"-0.002" to 0.000"Not RatedASME B17.1 Class 1595053A1080000
    3/4"Undersized-0.002" to 0.000"-0.002" to 0.000"Not RatedASME B17.1 Class 1595053A1310000
    1"Oversized0.000" to 0.001"0.000" to 0.001"Not RatedASME B17.1 Class 2595053A29200000
    1"Undersized-0.002" to 0.000"-0.002" to 0.000"Not RatedASME B17.1 Class 1595053A1350000
     

    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.
    1008-1045 Carbon Steel
    Image of Product. Front orientation. Machine Key Stock. Machine Key Stock.
    1008-1045 carbon 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.
    Undersized Tolerance—Slightly smaller than the size listed in the table, undersized stock is the choice when you need a slightly looser fit or when you have an inconsistent keyway. Use it when parts need to be taken apart frequently, such as for maintenance or prototyping.
    Tolerance
    Ht. × Wd.
    Tolerance
    Rating
    Ht.
    Wd.
    Min.
    Hardness
    Each
    12" Long
    1/8" × 1/8"Oversized0.000" to 0.002"0.000" to 0.002"Rockwell B5098830A10000000
    1/8" × 1/8"Undersized-0.002" to 0.000"-0.002" to 0.000"Rockwell B5098830A5140000
     
    36" Long
    1/8" × 1/8"Oversized0.000" to 0.002"0.000" to 0.002"Rockwell B5098830A7430000
    1/8" × 1/8"Undersized-0.002" to 0.000"-0.002" to 0.000"Rockwell B5098830A5150000
     
    72" Long
    1/8" × 1/8"Oversized0.000" to 0.002"0.000" to 0.002"Rockwell B5098830A5200000
     
    Zinc-Plated 1008-1045 Carbon Steel
    Image of Product. Front orientation. Machine Key Stock. Machine Key Stock.
    Zinc-plated 1008-1045 carbon steel key stock is an economical choice with good strength and resists corrosion in wet environments.
    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.
    Undersized Tolerance—Slightly smaller than the size listed in the table, undersized stock is the choice when you need a slightly looser fit or when you have an inconsistent keyway. Use it when parts need to be taken apart frequently, such as for maintenance or prototyping.
    Tolerance
    Ht. × Wd.
    Tolerance
    Rating
    Ht.
    Wd.
    Min.
    Hardness
    Each
    12" Long
    1/8" × 1/8"Oversized0.000" to 0.002"0.000" to 0.002"Rockwell B5098491A10000000
    1/8" × 1/8"Undersized-0.002" to 0.000"-0.002" to 0.000"Rockwell B5098510A1000000
     
    36" Long
    1/8" × 1/8"Undersized-0.002" to 0.000"-0.002" to 0.000"Rockwell B5098491A4140000
     
    1095 Spring Steel
    Image of Product. Front orientation. Machine Key Stock. Machine Key Stock.
    1095 spring steel key stock is an economical choice with good strength.
    Tolerance
    Ht. × Wd.
    Tolerance
    Rating
    Ht.
    Wd.
    Min.
    Hardness
    Each
    12" Long
    1/8" × 1/8"Standard-0.001" to 0.001"-0.001" to 0.001"Rockwell B9098535A13000000
     
    36" Long
    1/8" × 1/8"Standard-0.001" to 0.001"-0.001" to 0.001"Rockwell B9098535A41000000
     
    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.
    Undersized Tolerance—Slightly smaller than the size listed in the table, undersized stock is the choice when you need a slightly looser fit or when you have an inconsistent keyway. Use it when parts need to be taken apart frequently, such as for maintenance or prototyping.
    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 299020A41500000
    1/8" × 1/8"Undersized-0.002" to 0.000"-0.002" to 0.000"Not Rated—99020A7990000
     
    18-8 Stainless Steel
    Image of Product. Front orientation. Machine Key Stock. Machine Key Stock.
    18-8 stainless steel key stock offers a balance of strength and corrosion resistance. It may be mildly magnetic. 18-8 stainless steel key stock is more corrosion resistant than steel key stock.
    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.
    Undersized Tolerance—Slightly smaller than the size listed in the table, undersized stock is the choice when you need a slightly looser fit or when you have an inconsistent keyway. Use it when parts need to be taken apart frequently, such as for maintenance or prototyping.
    Tolerance
    Ht. × Wd.
    Tolerance
    Rating
    Ht.
    Wd.
    Min.
    Hardness
    Each
    12" Long
    1/8" × 1/8"Oversized0.000" to 0.003"0.000" to 0.003"Rockwell B8298493A10000000
    1/8" × 1/8"Undersized-0.002" to 0.000"-0.002" to 0.000"Rockwell B8292530A1000000
     
    36" Long
    1/8" × 1/8"Undersized-0.002" to 0.000"-0.002" to 0.000"Rockwell B8292530A3120000
     
    316/316L Stainless Steel
    Image of Product. Front orientation. Machine Key Stock. Machine Key Stock.
    316/316L stainless steel key stock has the best corrosion resistance of our stainless steel key stock and may be mildly magnetic. 316/316L stainless steel key stock is more corrosion resistant than steel key stock.
    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.
    Undersized Tolerance—Slightly smaller than the size listed in the table, undersized stock is the choice when you need a slightly looser fit or when you have an inconsistent keyway. Use it when parts need to be taken apart frequently, such as for maintenance or prototyping.
    Tolerance
    Ht. × Wd.
    Tolerance
    Rating
    Ht.
    Wd.
    Min.
    Hardness
    Each
    12" Long
    1/8" × 1/8"Oversized0.000" to 0.002"0.000" to 0.002"Not Rated98530A67300000
    1/8" × 1/8"Undersized-0.002" to 0.000"-0.002" to 0.000"Rockwell B8698530A1000000
    1/4" × 1/8"Oversized0.000" to 0.003"0.000" to 0.003"Not Rated98530A65600000
     
    36" Long
    1/8" × 1/8"Undersized-0.002" to 0.000"-0.002" to 0.000"Rockwell B8698530A41200000
     
    400 Nickel
    Image of Product. Front orientation. Machine Key Stock. Machine Key Stock.
    400 nickel key stock is the most corrosion resistant key stock in our offering and can be used in highly corrosive environments, such as those involving salt water, sulfuric acid, and alkalies. For complete corrosion resistance, 400 nickel keys are typically used with 400 nickel machine parts. Comparable to Monel, 400 nickel is also known for its strength and weldability.
    Undersized Tolerance—Slightly smaller than the size listed in the table, undersized stock is the choice when you need a slightly looser fit or when you have an inconsistent keyway. Use it when parts need to be taken apart frequently, such as for maintenance or prototyping.
    Tolerance
    Ht. × Wd.
    Tolerance
    Rating
    Ht.
    Wd.
    Min.
    Hardness
    Each
    12" Long
    1/8" × 1/8"Undersized-0.002" to 0.000"-0.002" to 0.000"Rockwell B614428N19000000
     
    36" Long
    1/8" × 1/8"Undersized-0.002" to 0.000"-0.002" to 0.000"Rockwell B614428N2100000
     
    360 Brass
    Image of Product. Front orientation. Machine Key Stock. Machine Key Stock.
    360 brass key stock is corrosion resistant and nonmagnetic. 360 brass is softer than other metals, so it's often used for shear keys.
    Tolerance
    Ht. × Wd.
    Tolerance
    Rating
    Ht.
    Wd.
    Min.
    Hardness
    Each
    12" Long
    1/8" × 1/8"Standard-0.0035" to 0.0035"-0.0035" to 0.0035"Rockwell B3598500A10000000
     
    36" Long
    1/8" × 1/8"Standard-0.0035" to 0.0035"-0.0035" to 0.0035"Rockwell B3598500A10100000
     
    6061 Aluminum
    Image of Product. Front orientation. Machine Key Stock. Machine Key Stock.
    6061 aluminum key stock is one-third the weight of steel key stock, but not as strong. It resists corrosion and is nonmagnetic.
    Tolerance
    Ht. × Wd.
    Tolerance
    Rating
    Ht.
    Wd.
    Min.
    Hardness
    Each
    12" Long
    1/8" × 1/8"Standard-0.008" to 0.008"-0.008" to 0.008"Not Rated99108A050000000
     

    High-Profile Woodruff Keys

    Image of Attribute. Front orientation. Contains Annotated. High-Profile Woodruff Keys.
    Image of Attribute. Side View. Front orientation. Contains Annotated. High-Profile Woodruff Keys.

    Side View

    Feet prevent these keys from rocking in the keyseat, making it easier to install gears and other components. Woodruff keys work well near shaft shoulders, where a standard open keyway would create too much stress. They are also often used on tapered shafts. Because they're usually shorter than standard machine keys, they work best in light duty applications. Keys are made of steel. Also known as hi-pro keys.
    Tolerance
    Woodruff
    Key No.
    Wd.
    Ht.
    For Keyway
    Dia.
    Lg.
    Wd.
    Ht.
    Feet
    Ht.
    Pkg.
    Qty.
    Pkg.
    1018-1045 Carbon Steel
    31/8"0.194"1/2"0.531"0.000" to 0.001"0.000" to 0.006"0.056"590049A17700000
    51/8"0.24"5/8"0.656"0.000" to 0.001"0.000" to 0.006"0.056"590049A5520000
    71/8"0.303"3/4"0.781"0.000" to 0.001"0.000" to 0.006"0.057"590049A3310000
     
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