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    39 Products

    Steel Headless Slotted Precision Shoulder Screws

    Image of Product. Front orientation. Shoulder Screws. Steel Headless Slotted Precision Shoulder Screws.
    With no head, you can flush mount these screws in counterbored holes and tight spaces. You can also use them as pins for aligning parts. They are engineered to tight tolerances for assemblies that require smooth and accurate movement, with shoulder diameters twice as precise as those on standard-fit screws. Hand-tighten with a slotted screwdriver to avoid damaging the drive.
    Shoulder
    Lg.
    Thread
    Size
    Thread
    Lg.
    Tensile
    Strength
    Pkg.
    Qty.
    Pkg.
    Alloy Steel
     
    1/8" Diameter Shoulder (-0.001" to 0" Tolerance)
    1/8"4-40
    		5/32"Not Rated194128A14100000
    1/4"4-40
    		5/32"Not Rated194128A1420000
    3/8"4-40
    		5/32"Not Rated194128A1430000
    1/2"4-40
    		5/32"Not Rated194128A1440000
    5/8"4-40
    		5/32"Not Rated194128A1450000
    3/4"4-40
    		5/32"Not Rated194128A1460000
     

    Stainless Steel Hex-Head Thumb Screws

    Image of Product. Front orientation. Thumb Screws. Stainless Steel Hex-Head Thumb Screws.
    When you need more torque than fingers alone can provide, crank these stainless steel thumb screws with a wrench. For finger tightening, the thick, hex-shaped head transmits added torque for a stronger hold than other head shapes. These thumb screws aren't recommended for structural, load-bearing applications.
    Length is measured from under the head.
    18-8 Stainless Steel—The choice for wet and outdoor environments, these screws resist rust. However, they won't hold up to the harsh chemicals that 316 stainless steel can.
    Head
    Lg.
    Wd.
    Ht.
    Threading
    Tensile Strength,
    psi
    Each
    18-8 Stainless Steel
     
    4-40
    1/2"3/8"1/4"Fully Threaded80,00090113A11000000
     

    Press-Fit Studs

    Image of Product. Front orientation. Studs. Press-Fit Studs.
    Press these studs into a drilled or punched hole with an arbor press or similar pressure tool. Also known as self-clinching studs, ribs under the head hold the stud firmly in place. Length listed is overall length.
    Zinc-Plated Steel—The most common choice for areas with occasional exposure to moisture.
    18-8 Stainless Steel—The choice for wet and outdoor environments, these studs resist rust. However, they won't hold up to the harsh chemicals that 316 stainless steel can.
    Lg.
    PEM® Part
    No.
    Thread
    Lg.
    For Min.
    Material Thk.
    For Min. Lg. Between Hole
    Ctr. and Sheet Edge
    For Hole
    Dia.
    Hole Size
    Tolerance
    Drill Bit
    Size
    Base
    Dia.
    Tensile
    Strength
    Hardness
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
     
    4-40
    1/4"FH-440-45/32"0.040"7/32"0.111"0.000" to 0.003"34 Ga.
    		0.191"Not RatedNot Rated10093580A00400000
    5/16"FH-440-515/64"0.040"7/32"0.111"0.000" to 0.003"34 Ga.
    		0.191"Not RatedNot Rated5093580A5470000
    3/8"FH-440-69/32"0.040"7/32"0.111"0.000" to 0.003"34 Ga.
    		0.191"Not RatedNot Rated10093580A0060000
    1/2"FH-440-813/32"0.040"7/32"0.111"0.000" to 0.003"34 Ga.
    		0.191"Not RatedNot Rated10093580A0080000
    5/8"FH-440-1017/32"0.040"7/32"0.111"0.000" to 0.003"34 Ga.
    		0.191"Not RatedNot Rated5093580A0100000
    3/4"FH-440-1243/64"0.040"7/32"0.111"0.000" to 0.003"34 Ga.
    		0.191"Not RatedNot Rated5093580A5480000
    7/8"FH-440-1451/64"0.040"7/32"0.111"0.000" to 0.003"34 Ga.
    		0.191"Not RatedNot Rated2593580A5490000
    1"FH-440-1659/64"0.040"7/32"0.111"0.000" to 0.003"34 Ga.
    		0.191"Not RatedNot Rated2593580A5510000
    1 1/4"FH-440-201 11/64"0.040"7/32"0.111"0.000" to 0.003"34 Ga.
    		0.191"Not RatedNot Rated2593580A5520000
     
    18-8 Stainless Steel
     
    4-40
    1/4"FHS-440-45/32"0.040"7/32"0.111"0.000" to 0.003"34 Ga.
    		0.191"Not RatedNot Rated5093580A6470000
    5/16"FHS-440-57/32"0.040"7/32"0.111"0.000" to 0.003"34 Ga.
    		0.191"Not RatedNot Rated5093580A6480000
    3/8"FHS-440-69/32"0.040"7/32"0.111"0.000" to 0.003"34 Ga.
    		0.191"Not RatedNot Rated5093580A1150000
    1/2"FHS-440-813/32"0.040"7/32"0.111"0.000" to 0.003"34 Ga.
    		0.191"Not RatedNot Rated5093580A1200000
    5/8"FHS-440-1035/64"0.040"7/32"0.111"0.000" to 0.003"34 Ga.
    		0.191"Not RatedNot Rated2593580A6490000
    3/4"FHS-440-1221/32"0.040"7/32"0.111"0.000" to 0.003"34 Ga.
    		0.191"Not RatedNot Rated2593580A6510000
    7/8"FHS-440-1451/64"0.040"7/32"0.111"0.000" to 0.003"34 Ga.
    		0.191"Not RatedNot Rated1093580A6520000
    1"FHS-440-1629/32"0.040"7/32"0.111"0.000" to 0.003"34 Ga.
    		0.191"Not RatedNot Rated1093580A6530000
     

    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 290164A23100000
    3/4"Oversized0.000" to 0.001"0.000" to 0.001"Not Rated4-40
    		ASME B17.1 Class 290164A3140000
    1"Oversized0.000" to 0.001"0.000" to 0.001"Not Rated4-40
    		ASME B17.1 Class 290164A3150000
    1 1/2"Oversized0.000" to 0.001"0.000" to 0.001"Not Rated4-40
    		ASME B17.1 Class 290164A4070000
    1 3/4"Oversized0.000" to 0.001"0.000" to 0.001"Not Rated4-40
    		ASME B17.1 Class 290164A4810000
    2"Oversized0.000" to 0.001"0.000" to 0.001"Not Rated4-40
    		ASME B17.1 Class 290164A5690000
     

    Threaded Plug Gauges

    Test if internal threads fall within tolerance. These plug gauges are often used in nuts and tapped holes to confirm thread fit. For precision and accuracy, they’re manufactured to tight tolerances.
    Threads are within tolerance if it’s easy to thread a go gauge but difficult to thread a no-go gauge more than two turns.
    Class X Gauge
    Image of Product. Front orientation. Plug Gauges. Threaded Plug Gauges.
    Go Gauge—Go gauges check the minimum hole diameter.
    No-Go Gauge—No-go gauges check the maximum hole diameter.
    Accuracy Certificate Traceable to NIST—Gauges with an accuracy certificate traceable to NIST include verification from the manufacturer that their thread sizes are within tolerance. The certificate is also known as a certificate of compliance or a short-form certification.
    For Class 2B Unified Standard Thread Fit—For inch threads, the higher the class number, the tighter the fit. Unified Standard Class 2B is standard and works for most applications.
    For Thread Fit—Thread fit designates the tightness or looseness of mating threads.
    Thread
    Size
    Thread
    Type
    Pitch Dia.
    Tolerance
    Hardness
    Material
    For Thread Fit
    Each
    Go Gauges
    4-40
    		UNC
    		0" to 0.0002"Rockwell C70Chrome-Plated Tool SteelUnified Standard Class 2B, Unified Standard Class 3B
    		7968N13000000
     
    Go Gauges with Accuracy Certificate Traceable to NIST
    4-40
    		UNC
    		0" to 0.0002"Rockwell C70Chrome-Plated Tool SteelUnified Standard Class 2B, Unified Standard Class 3B
    		7968N10300000
     
    No-Go Gauges
    4-40
    		UNC
    		-0.0002" to 0"Rockwell C70Chrome-Plated Tool SteelUnified Standard Class 2B
    		7968N4700000
     
    No-Go Gauges with Accuracy Certificate Traceable to NIST
    4-40
    		UNC
    		-0.0002" to 0"Rockwell C70Chrome-Plated Tool SteelUnified Standard Class 2B
    		7968N13700000
     

    Stud Welders

    Join threaded studs and pins to metal surfaces in milliseconds, forming bonds stronger than the studs themselves. Just load a stud into the gun, aim it against your base material, and pull the trigger to fuse the two together.
    Unlike drawn arc stud welders, our capacitor discharge systems work with metals less than a millimeter thick. They won’t leave fastener heads on the opposite side of the base material, so they’re often used for jobs requiring a clean-looking finish, such as attaching handles to high-end cookware. The one-sided welds are also preferred by the USDA for fabricating dairy tanks and other food-safe machinery – with no holes drilled, germs have nowhere to hide.
    Threaded Studs
    Image of Product. Front orientation. Stud Welders. Threaded Studs.
    • Suitable for steel and stainless steel base materials, as well as aluminum and brass
    Copper-Plated Steel—Copper-plated steel studs have good corrosion resistance.
    Copper-Plated Steel
    Thread
    Size
    For Collet
    Thread Size
    Head
    Dia.
    Lg.
    Pkg.
    Qty.
    Pkg.
    4-40
    		4-40
    		3/16"1/2"1007845A55000000
     

    Go/No-Go Threaded Plug Gauges with Handle

    Speed up thread tolerance checks—the handle on these gauges gives you a good grip to quickly thread and unthread go or no-go gauges. Use these gauges to make sure nuts, tapped holes, and other parts fall within tolerance. All are precisely manufactured to confirm thread fit. If the plug gauges wear down, you can insert new ones (not included) onto the taperlock handle.
    A part is within tolerance if it’s easy to thread the go gauge into the part but difficult to thread the no-go gauge more than two turns.
    Go/no-go gauges have both a go gauge on one end of the handle and a no-go gauge on the other to speed up tests. Go gauges check the minimum internal thread size. No-go gauges check the maximum internal thread size.
    Class X Gauge
    Image of Product. Double-Ended Taperlock Handle. Front orientation. Plug Gauges. Go/No-Go Threaded Plug Gauges with Handle.

    Double-Ended Taperlock

    Handle

    Calibration Certificate Traceable to NIST—Gauges with a calibration certificate traceable to NIST were calibrated in a lab. The certificate, sometimes called a test report or long-form certificate, details the tested measurements.
    For Class 2B Unified Standard Thread Fit—For inch threads, the higher the class number, the tighter the fit. Unified Standard Class 2B is standard and works for most applications.
    For Thread Fit—Thread fit designates the tightness or looseness of mating threads.
    Thread
    Size
    Thread
    Type
    Pitch Dia.
    Tolerance
    Hardness
    Material
    Features
    Choose a Thread Fit
    Each
    Go/No-Go Gauges
    4-40
    		UNC
    		-0.0002" to 0.0002"Rockwell C70Chrome-Plated Tool SteelDouble-Ended Taperlock Handle
    Unified Standard Class 2B
    ,
    Unified Standard Class 3B
    		2366A5080000000
     
    Go/No-Go Gauges with Calibration Certificate Traceable to NIST
    4-40
    		UNC
    		-0.0002" to 0.0002"Rockwell C70Chrome-Plated Tool SteelDouble-Ended Taperlock Handle
    Unified Standard Class 2B
    ,
    Unified Standard Class 3B
    		3157A17000000
     

    Go/No-Go Helical Insert Threaded Plug Gauges with Handle

    Image of Product. Front orientation. Plug Gauges. Go/No-Go Helical Insert Threaded Plug Gauges with Handle.
    Check that holes tapped for helical threads are within tolerance. You’ll sometimes hear these threads referred to as Screw Thread Insert (STI) threads. To speed up tests, these gauges have a go gauge on one end and a no-go gauge on the other. The double-ended taperlock handle makes them quick to thread and unthread. It also lets you swap in new plug gauges (not included) in place of worn ones.
    The go gauge checks the minimum internal thread size, and the no-go gauge checks the maximum. A part is within tolerance if it’s easy to thread the go gauge but difficult to thread the no-go gauge more than two turns.
    Plug Gauges with Accuracy Certificate Traceable to NIST—Gauges with an accuracy certificate traceable to NIST include verification from the manufacturer that their thread sizes are within tolerance. The certificate is also known as a certificate of compliance or a short-form certification.
    Plug Gauges with Calibration Certificate Traceable to NIST—Gauges with a calibration certificate traceable to NIST were calibrated in a lab. The certificate, sometimes called a test report or long-form certificate, details the tested measurements.
    Plug Gauges with Accuracy
    Certificate Traceable to NIST
    Plug Gauges with Calibration
    Certificate Traceable to NIST
    Thread
    Size
    Thread
    Type
    Pitch Dia.
    Tolerance
    Hardness
    Material
    Features
    For Thread Fit
    Each
    Each
    Class X Gauge
    4-40
    		UNC
    		-0.0002" to 0.0002"Rockwell C70Chrome-Plated Tool SteelDouble-Ended Taperlock HandleUnified Standard Class 2B
    		7941N1200000007941N290000000
     
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