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    35 Products

    Partially Grooved Dowel Pins
    3D CAD models available

    The grooved section secures these pins while the smooth portion is free to act as a pivot or hinge. The grooves pinch shut when installed, creating tension to lock in place. They fit tighter than standard dowel pins and resist pulling from movement and vibration, even in imperfect holes.
    For the best fit, drill your hole slightly larger than the nominal diameter shown.
    Center Grooved
    Image of ProductInUse. Front orientation. Dowel Pins. Partially Grooved Dowel Pins, Center Grooved.
    Image of Product. Front orientation. Dowel Pins. Partially Grooved Dowel Pins, Center Grooved, Parallel Groove.

    Parallel Groove

    These pins lock in the middle, leaving two smooth ends free. They're often used to create a T-handle, such as on a valve stem to open and close it by hand. Also known as type E pins.
    Zinc-Plated Carbon Steel—These pins withstand occasional exposure to moisture. However, since friction from moving parts can wear away the finish, they're not ideal for wet environments. While not nearly as corrosion resistant as stainless steel, they are stronger and won’t deform under stress.
    Parallel Groove—Fit tighter than pins with tapered grooves to stay in place under severe vibration. However, they require more force to insert.
    Nominal
    Max.
    Lg.
    Dia.
    Dia. Tolerance
    Dia.
    Dia. Tolerance
    Groove
    Type
    Breaking Strength,
    lbf
    Min.
    Hardness
    Groove
    Lg.
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Carbon Steel
     
    3/32" Diameter
    1/4"0.094"-0.002" to 0"0.101"-0.003" to 0.003"Parallel850Not Rated1/8"__25000000000000000
    1/2"0.094"-0.002" to 0"0.101"-0.003" to 0.003"Parallel850Not Rated1/4"__2500000000000000
     
    1/8" Diameter
    1/2"0.125"-0.002" to 0"0.134"-0.003" to 0.003"Parallel1,600Not Rated1/4"__2500000000000000
    3/4"0.125"-0.002" to 0"0.134"-0.003" to 0.003"Parallel1,600Not Rated3/8"__2500000000000000
    1"0.125"-0.002" to 0"0.133"-0.003" to 0.003"Parallel1,600Not Rated1/2"__2500000000000000
     
    5/32" Diameter
    1/2"0.156"-0.002" to 0"0.166"-0.003" to 0.003"Parallel2,300Not Rated1/4"__2500000000000000
    3/4"0.156"-0.002" to 0"0.166"-0.003" to 0.003"Parallel2,300Not Rated3/8"__2500000000000000
    1"0.156"-0.002" to 0"0.165"-0.003" to 0.003"Parallel2,300Not Rated1/2"__2500000000000000
     
    3/16" Diameter
    1/2"0.188"-0.002" to 0"0.198"-0.003" to 0.003"Parallel3,300Not Rated1/4"__2500000000000000
    3/4"0.188"-0.002" to 0"0.198"-0.003" to 0.003"Parallel3,300Not Rated3/8"__2500000000000000
    1"0.188"-0.002" to 0"0.198"-0.003" to 0.003"Parallel3,300Not Rated1/2"__100000000000000
    1 1/2"0.188"-0.002" to 0"0.197"-0.003" to 0.003"Parallel3,300Not Rated3/4"__1000000000000000
     
    1/4" Diameter
    3/4"0.25"-0.002" to 0"0.263"-0.003" to 0.003"Parallel5,800Not Rated3/8"__2500000000000000
    1"0.25"-0.002" to 0"0.263"-0.003" to 0.003"Parallel5,800Not Rated1/2"__2500000000000000
    1 1/4"0.25"-0.002" to 0"0.263"-0.003" to 0.003"Parallel5,800Not Rated5/8"__100000000000000
    1 1/2"0.25"-0.002" to 0"0.262"-0.003" to 0.003"Parallel5,800Not Rated3/4"__1000000000000000
     
    5/16" Diameter
    3/4"0.313"-0.002" to 0"0.329"-0.003" to 0.003"Parallel7,600Not Rated3/8"__100000000000000
    1"0.313"-0.002" to 0"0.329"-0.003" to 0.003"Parallel7,600Not Rated1/2"__100000000000000
    1 1/4"0.313"-0.002" to 0"0.329"-0.003" to 0.003"Parallel7,600Not Rated5/8"__100000000000000
     
    3/8" Diameter
    1"0.375"-0.002" to 0"0.394"-0.003" to 0.003"Parallel11,000Not Rated1/2"__1000000000000000
     
    2 mm Diameter
    12 mm2 mm-0.025 mm to 0 mm2.1 mm0 mm to 0.05 mmParallel600Rockwell B684 mmISO 874210000000000000
     
    2.5 mm Diameter
    24 mm2.5 mm-0.025 mm to 0 mm2.65 mm-0.05 mm to 0.05 mmParallel950Rockwell B688 mmISO 874210000000000000
     
    3 mm Diameter
    12 mm3 mm-0.025 mm to 0 mm3.1 mm-0.05 mm to 0.05 mmParallel1,400Rockwell B684 mmISO 874210000000000000
    14 mm3 mm-0.025 mm to 0 mm3.1 mm-0.05 mm to 0.05 mmParallel1,400Rockwell B684.66 mmISO 874210000000000000
    16 mm3 mm-0.025 mm to 0 mm3.1 mm-0.05 mm to 0.05 mmParallel1,400Rockwell B685.33 mmISO 874210000000000000
    22 mm3 mm-0.025 mm to 0 mm3.15 mm-0.05 mm to 0.05 mmParallel1,400Rockwell B687.33 mmISO 874210000000000000
    24 mm3 mm-0.025 mm to 0 mm3.15 mm-0.05 mm to 0.05 mmParallel1,400Rockwell B688 mmISO 874210000000000000
     
    4 mm Diameter
    16 mm4 mm-0.075 mm to 0 mm4.15 mm-0.05 mm to 0.05 mmParallel2,500Rockwell B685.33 mmISO 874210000000000000
    18 mm4 mm-0.075 mm to 0 mm4.15 mm-0.05 mm to 0.05 mmParallel2,500Rockwell B686 mmISO 874210000000000000
    24 mm4 mm-0.075 mm to 0 mm4.2 mm-0.05 mm to 0.05 mmParallel2,500Rockwell B688 mmISO 874210000000000000
     
    5 mm Diameter
    22 mm5 mm-0.075 mm to 0 mm5.2 mm-0.05 mm to 0.05 mmParallel3,950Rockwell B687.33 mmISO 8742100000000000000
    26 mm5 mm-0.075 mm to 0 mm5.2 mm-0.05 mm to 0.05 mmParallel3,950Rockwell B688.66 mmISO 8742100000000000000
    32 mm5 mm-0.075 mm to 0 mm5.25 mm-0.05 mm to 0.05 mmParallel3,950Rockwell B6810.66 mmISO 8742100000000000000
     
    6 mm Diameter
    28 mm6 mm-0.075 mm to 0 mm6.25 mm-0.05 mm to 0.05 mmParallel5,700Rockwell B689.33 mmISO 8742100000000000000
     
    8 mm Diameter
    32 mm8 mm-0.09 mm to 0 mm8.25 mm-0.05 mm to 0.05 mmParallel10,150Rockwell B6810.66 mmISO 874250000000000000
     
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