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    94 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 and 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.
    316 Stainless Steel—316 stainless steel keys have excellent corrosion resistance, but aren't as strong as steel keys. 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. Undersized metric keys meet DIN 6885 dimensional standards.
    Tolerance,
    mm
    Lg.,
    mm
    Tolerance
    Rating
    Ht.
    Wd.
    Min.
    Hardness
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    1008-1045 Carbon Steel
     
    5 mm × 5 mm
    22Undersized-0.030 to 0.000-0.030 to 0.000Not RatedDIN 6885596717A17300000
    28Undersized-0.030 to 0.000-0.030 to 0.000Not RatedDIN 6885596717A2020000
    32Undersized-0.030 to 0.000-0.030 to 0.000Not RatedDIN 6885596717A2180000
    36Undersized-0.030 to 0.000-0.030 to 0.000Not RatedDIN 6885596717A2670000
    45Undersized-0.030 to 0.000-0.030 to 0.000Not RatedDIN 6885596717A2850000
     
    1045 Carbon Steel
     
    5 mm × 5 mm
    10Undersized-0.030 to 0.000-0.030 to 0.000Rockwell B87DIN 68851096717A1480000
    12Undersized-0.030 to 0.000-0.030 to 0.000Rockwell B87DIN 68851096717A1490000
    14Undersized-0.030 to 0.000-0.030 to 0.000Rockwell B87DIN 68851096717A15000000
    16Undersized-0.030 to 0.000-0.030 to 0.000Rockwell B87DIN 68851096717A1600000
    18Undersized-0.030 to 0.000-0.030 to 0.000Rockwell B87DIN 68851096717A17000000
    20Oversized0.000 to 0.0760.000 to 0.076Rockwell B87—596717A1420000
    20Undersized-0.030 to 0.000-0.030 to 0.000Rockwell B87DIN 68851096717A1800000
    25Oversized0.000 to 0.0760.000 to 0.076Rockwell B87—596717A1750000
    25Undersized-0.030 to 0.000-0.030 to 0.000Rockwell B87DIN 68851096717A1900000
    30Undersized-0.030 to 0.000-0.030 to 0.000Rockwell B87DIN 6885196717A1920000
    40Undersized-0.030 to 0.000-0.030 to 0.000Rockwell B87DIN 6885196717A1940000
    50Undersized-0.030 to 0.000-0.030 to 0.000Rockwell B87DIN 6885196717A1960000
     
    316 Stainless Steel
     
    5 mm × 5 mm
    8Undersized-0.030 to 0.000-0.030 to 0.000Not RatedDIN 688552977N6900000
    10Undersized-0.030 to 0.000-0.030 to 0.000Not RatedDIN 688552977N2200000
    12Undersized-0.030 to 0.000-0.030 to 0.000Not RatedDIN 688552977N2300000
    14Undersized-0.030 to 0.000-0.030 to 0.000Not RatedDIN 688552977N2400000
    15Undersized-0.030 to 0.000-0.030 to 0.000Not RatedDIN 688552977N7100000
    16Undersized-0.030 to 0.000-0.030 to 0.000Not RatedDIN 688552977N2500000
    18Undersized-0.030 to 0.000-0.030 to 0.000Not RatedDIN 688512977N260000
    20Undersized-0.030 to 0.000-0.030 to 0.000Not RatedDIN 6885196717A1810000
    22Undersized-0.030 to 0.000-0.030 to 0.000Not RatedDIN 688552977N7200000
    25Undersized-0.030 to 0.000-0.030 to 0.000Not RatedDIN 688512977N280000
    28Undersized-0.030 to 0.000-0.030 to 0.000Not RatedDIN 688552977N7300000
    30Undersized-0.030 to 0.000-0.030 to 0.000Not RatedDIN 6885196717A1930000
    35Undersized-0.030 to 0.000-0.030 to 0.000Not RatedDIN 688552977N7500000
    36Undersized-0.030 to 0.000-0.030 to 0.000Not RatedDIN 688512977N760000
    40Undersized-0.030 to 0.000-0.030 to 0.000Not RatedDIN 688512977N310000
    45Undersized-0.030 to 0.000-0.030 to 0.000Not RatedDIN 688512977N770000
    50Undersized-0.030 to 0.000-0.030 to 0.000Not RatedDIN 688512977N320000
    60Undersized-0.030 to 0.000-0.030 to 0.000Not RatedDIN 688512977N810000
    63Undersized-0.030 to 0.000-0.030 to 0.000Not RatedDIN 688512977N820000
    70Undersized-0.030 to 0.000-0.030 to 0.000Not RatedDIN 688512977N830000
     

    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 and 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.
    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.
    Tolerance,
    mm
    Lg.,
    mm
    Tolerance
    Rating
    Ht.
    Wd.
    Min.
    Hardness
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    1008-1045 Carbon Steel
     
    5 mm × 5 mm
    10Undersized-0.030 to 0.000-0.030 to 0.000Not RatedDIN 6885598870A72400000
    12Undersized-0.030 to 0.000-0.030 to 0.000Not RatedDIN 6885598870A7250000
    14Undersized-0.030 to 0.000-0.030 to 0.000Not RatedDIN 6885598870A7260000
    16Undersized-0.030 to 0.000-0.030 to 0.000Not RatedDIN 6885598870A7270000
    18Undersized-0.030 to 0.000-0.030 to 0.000Not RatedDIN 6885598870A7290000
    20Undersized-0.030 to 0.000-0.030 to 0.000Not RatedDIN 6885598870A7310000
    22Undersized-0.030 to 0.000-0.030 to 0.000Not RatedDIN 6885598870A7320000
    25Undersized-0.030 to 0.000-0.030 to 0.000Not RatedDIN 6885598870A7330000
    28Undersized-0.030 to 0.000-0.030 to 0.000Not RatedDIN 6885598870A7340000
    30Undersized-0.030 to 0.000-0.030 to 0.000Not RatedDIN 6885598870A7350000
    32Undersized-0.030 to 0.000-0.030 to 0.000Not RatedDIN 6885598870A7360000
    36Undersized-0.030 to 0.000-0.030 to 0.000Not RatedDIN 6885598870A7370000
    40Undersized-0.030 to 0.000-0.030 to 0.000Not RatedDIN 6885598870A7380000
    45Undersized-0.030 to 0.000-0.030 to 0.000Not RatedDIN 6885598870A7390000
    50Undersized-0.030 to 0.000-0.030 to 0.000Not RatedDIN 6885598870A7410000
     
    1045 Carbon Steel
     
    5 mm × 5 mm
    20Oversized0.000 to 0.0760.000 to 0.076Rockwell B87—598870A3450000
    25Oversized0.000 to 0.0760.000 to 0.076Rockwell B87—598870A3470000
     
    316 Stainless Steel
     
    5 mm × 5 mm
    8Undersized-0.030 to 0.000-0.030 to 0.000Not RatedDIN 6885598870A2130000
    10Undersized-0.030 to 0.000-0.030 to 0.000Not RatedDIN 6885598870A2170000
    12Undersized-0.030 to 0.000-0.030 to 0.000Not RatedDIN 6885598870A2200000
    15Undersized-0.030 to 0.000-0.030 to 0.000Not RatedDIN 6885598870A2280000
    16Undersized-0.030 to 0.000-0.030 to 0.000Not RatedDIN 6885598870A2370000
    18Undersized-0.030 to 0.000-0.030 to 0.000Not RatedDIN 6885598870A2440000
    20Undersized-0.030 to 0.000-0.030 to 0.000Not RatedDIN 6885598870A2460000
    25Undersized-0.030 to 0.000-0.030 to 0.000Not RatedDIN 6885598870A25000000
    30Undersized-0.030 to 0.000-0.030 to 0.000Not RatedDIN 6885598870A26200000
    35Undersized-0.030 to 0.000-0.030 to 0.000Not RatedDIN 6885598870A27300000
    40Undersized-0.030 to 0.000-0.030 to 0.000Not RatedDIN 6885598870A27800000
    50Undersized-0.030 to 0.000-0.030 to 0.000Not RatedDIN 6885598870A29500000
    55Undersized-0.030 to 0.000-0.030 to 0.000Not RatedDIN 6885598870A29700000
    70Undersized-0.030 to 0.000-0.030 to 0.000Not RatedDIN 6885198870A3130000
     

    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—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.
    Metric—Metric keys conform to DIN 6888 standards.
    Tolerance,
    mm
    Wd.,
    mm
    For Keyway
    Dia., mm
    Ht.,
    mm
    Lg.,
    mm
    Wd.
    Ht.
    Specs.
    Met
    System of
    Measurement
    Pkg.
    Qty.
    Pkg.
    1018-1045 Carbon Steel
    5166.515.7-0.030 to 0.000—DIN 6888Metric2598490A220000000
    5197.518.6-0.030 to 0.000—DIN 6888Metric2598490A23000000
    522921.6-0.030 to 0.000—DIN 6888Metric2598490A24000000
    5251024.5-0.030 to 0.000—DIN 6888Metric1098490A25000000
     
    316 Stainless Steel
    5166.515.7-0.030 to 0.000-0.150 to 0.000DIN 6888Metric197940A13700000
    5197.518.6-0.030 to 0.000-0.150 to 0.000DIN 6888Metric197940A13800000
     

    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.
    DIN 6880—Key stock that meets DIN 6880 conforms to DIN standards for undersized keys.
    Tolerance,
    mm
    Ht. × Wd.
    Tolerance
    Rating
    Ht.
    Wd.
    Min.
    Hardness
    Specs.
    Met
    Each
    305 mm Long
    3 mm × 5 mmUndersized-0.060 to 0.000-0.030 to 0.000Rockwell B87DIN 688092288A51700000
    5 mm × 5 mmOversized0.000 to 0.0760.000 to 0.076Rockwell B87—92288A4930000
    5 mm × 5 mmUndersized-0.030 to 0.000-0.030 to 0.000Rockwell B87DIN 688092288A7250000
     
    1,000 mm Long
    3 mm × 5 mmUndersized-0.060 to 0.000-0.030 to 0.000Rockwell B87DIN 688092288A55200000
    5 mm × 5 mmUndersized-0.030 to 0.000-0.030 to 0.000Rockwell B87DIN 688092288A5660000
     
    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.
    Tolerance,
    mm
    Ht. × Wd.
    Tolerance
    Rating
    Ht.
    Wd.
    Min.
    Hardness
    Each
    305 mm Long
    5 mm × 5 mmOversized0.000 to 0.0760.000 to 0.076Rockwell B8792288A12000000
     
    Zinc-Yellow-Chromate-Plated 1045 Carbon Steel
    Image of Product. Front orientation. Machine Key Stock. Machine Key Stock.
    Zinc-yellow-chromate-plated 1045 carbon steel key stock is an economical choice with good strength and resists corrosion in wet environments.
    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.
    DIN 6880—Key stock that meets DIN 6880 conforms to DIN standards for undersized keys.
    Tolerance,
    mm
    Ht. × Wd.
    Tolerance
    Rating
    Ht.
    Wd.
    Min.
    Hardness
    Specs.
    Met
    Each
    305 mm Long
    5 mm × 5 mmUndersized-0.030 to 0.000-0.030 to 0.000Rockwell B87DIN 688092288A76600000
     
    4140 Alloy Steel
    Image of Product. Front orientation. Machine Key Stock. Machine Key Stock.
    4140 alloy steel key stock is an economical choice with good strength. 4140 alloy steel key stock has greater strength and toughness after hardening than carbon steel, making it useful for high-stress applications.
    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.
    DIN 6880—Key stock that meets DIN 6880 conforms to DIN standards for undersized keys.
    Tolerance,
    mm
    Ht. × Wd.
    Tolerance
    Rating
    Ht.
    Wd.
    Min.
    Hardness
    Specs.
    Met
    Each
    305 mm Long
    5 mm × 5 mmUndersized-0.030 to 0.000-0.030 to 0.000Rockwell B90DIN 688092288A65800000
     
    1,000 mm Long
    5 mm × 5 mmUndersized-0.030 to 0.000-0.030 to 0.000Rockwell B90DIN 688092288A66900000
     
    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.
    DIN 6880—Key stock that meets DIN 6880 conforms to DIN standards for undersized keys.
    Tolerance,
    mm
    Ht. × Wd.
    Tolerance
    Rating
    Ht.
    Wd.
    Min.
    Hardness
    Specs.
    Met
    Each
    305 mm Long
    5 mm × 5 mmOversized0.000 to 0.0760.000 to 0.076Rockwell B82DIN 17898810A11000000
    5 mm × 5 mmUndersized-0.030 to 0.000-0.030 to 0.000Not RatedDIN 688090457A4300000
     
    304 Stainless Steel
    Image of Product. Front orientation. Machine Key Stock. Machine Key Stock.
    304 stainless steel key stock offers a good balance of strength, corrosion resistance, and machinability. 304 stainless steel key stock is more corrosion resistant than steel key stock.
    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.
    DIN 6880—Key stock that meets DIN 6880 conforms to DIN standards for undersized keys.
    Tolerance,
    mm
    Ht. × Wd.
    Tolerance
    Rating
    Ht.
    Wd.
    Min.
    Hardness
    Specs.
    Met
    Each
    1,000 mm Long
    3 mm × 5 mmUndersized-0.060 to 0.000-0.030 to 0.000Rockwell B80DIN 688092288A614000000
    5 mm × 5 mmUndersized-0.030 to 0.000-0.030 to 0.000Rockwell B80DIN 688092288A61600000
     
    316 Stainless Steel
    Image of Product. Front orientation. Machine Key Stock. Machine Key Stock.
    316 stainless steel key stock has the best corrosion resistance of our stainless steel key stock and may be mildly magnetic. 316 stainless steel key stock is more corrosion resistant than steel key stock.
    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.
    DIN 6880—Key stock that meets DIN 6880 conforms to DIN standards for undersized keys.
    Tolerance,
    mm
    Ht. × Wd.
    Tolerance
    Rating
    Ht.
    Wd.
    Min.
    Hardness
    Specs.
    Met
    Each
    1,000 mm Long
    3 mm × 5 mmUndersized-0.060 to 0.000-0.030 to 0.000Rockwell B85DIN 688092288A637000000
    5 mm × 5 mmUndersized-0.030 to 0.000-0.030 to 0.000Rockwell B85DIN 688092288A63900000
     
    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.
    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.
    DIN 6880—Key stock that meets DIN 6880 conforms to DIN standards for undersized keys.
    Tolerance,
    mm
    Ht. × Wd.
    Tolerance
    Rating
    Ht.
    Wd.
    Min.
    Hardness
    Specs.
    Met
    Each
    305 mm Long
    5 mm × 5 mmUndersized-0.030 to 0.000-0.030 to 0.000Rockwell B86DIN 688090457A13000000
     
    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.
    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.
    DIN 6880—Key stock that meets DIN 6880 conforms to DIN standards for undersized keys.
    Tolerance,
    mm
    Ht. × Wd.
    Tolerance
    Rating
    Ht.
    Wd.
    Min.
    Hardness
    Specs.
    Met
    Each
    305 mm Long
    5 mm × 5 mmUndersized-0.030 to 0.000-0.030 to 0.000Rockwell B35DIN 688090457A730000000
     

    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.
    Undersized Tolerance—Undersized keys are good when you need a slightly looser fit or when you have an inconsistent keyway. Use them with parts you take apart frequently, such as for maintenance or prototyping. They meet DIN 6885 dimensional standards for undersized keys.
    Tolerance,
    mm
    Lg.,
    mm
    Tolerance
    Rating
    Ht.
    Wd.
    Min.
    Hardness
    Thread
    Size
    Specs.
    Met
    Each
    1018-1045 Carbon Steel
     
    5 mm × 5 mm
    20Undersized-0.030 to 0.000-0.030 to 0.000Not RatedM3 × 0.5 mmDIN 688590164A10100000
    25Undersized-0.030 to 0.000-0.030 to 0.000Not RatedM3 × 0.5 mmDIN 688590164A1030000
    40Undersized-0.030 to 0.000-0.030 to 0.000Not RatedM3 × 0.5 mmDIN 688590164A1080000
     
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