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    42 Products

    Ball-Nose Spring Plungers

    Image of Product. Front orientation. Spring Plungers. Ball-Nose Spring Plungers.
    Image of Attribute. Front orientation. Contains Annotated. Ball-Nose Spring Plungers.
    Align, position, and lock moving parts for most machining and assembly tasks. These spring plungers have a spring-loaded ball that compresses when a part presses against it, and then pops out into a notch or groove to hold the part in place. Unlike long-nose spring plungers, the ball rolls easily in and out of position, so they're a great fit for applications that require consistent, smooth movement, such as positioning parts in an assembly line and aligning fixtures and jigs when cutting or drilling.
    Spring plungers are available with or without a threadlocker. Those with a threadlocker won't wiggle loose from vibration. Spring plungers without a threadlocker are easier to remove.
    440C Stainless Steel Nose—The strongest, most wear-resistant stainless steel noses, these grind against hard metal surfaces without denting or scratching. However, they are not as corrosion resistant as 316 stainless steel.
    Nylon Nose—Extra soft to avoid scratching delicate surfaces. Nylon is best for use on soft materials, such as aluminum. It will swell and weaken when exposed to moisture, however, so it should only be used in dry environments.
    Extended Nose Force—This is the amount of force needed to start depressing the nose.
    Compressed Nose Force—This is the amount of force needed to fully depress the nose into the plunger body, so it releases from a hole, notch, or surface. A lighter compressed nose force with a shallower hole releases more easily, while a heavier compressed nose force with a deeper hole holds more securely.
    Nose
    Nose
    Force, lbf
    Body
    Thread
    Size
    Extended
    Lg.
    Dia.
    Extended
    Compressed
    Material
    Lg.
    Drive Style
    - 2
    Each
    440C Stainless Steel Nose
    1/4"-20
    0.03"0.125"12.5Acetal
    0.53"Slotted
    0000000000000
    1/4"-20
    0.03"0.125"25Acetal
    0.53"Slotted
    000000000000
    5/16"-18
    0.039"0.156"24.5Acetal
    0.58"Slotted
    000000000000
    5/16"-18
    0.039"0.156"49Acetal
    0.58"Slotted
    000000000000
    3/8"-16
    0.053"0.187"2.55Acetal
    0.63"Slotted
    000000000000
    3/8"-16
    0.053"0.187"510Acetal
    0.63"Slotted
    000000000000
     
    Nylon Nose
    1/4"-20
    0.03"0.125"12.5Acetal
    0.53"Slotted
    000000000000
    1/4"-20
    0.03"0.125"25Acetal
    0.53"Slotted
    000000000000
    5/16"-18
    0.039"0.156"24.5Acetal
    0.58"Slotted
    000000000000
    5/16"-18
    0.039"0.156"49Acetal
    0.58"Slotted
    000000000000
    3/8"-16
    0.053"0.187"2.55Acetal
    0.63"Slotted
    000000000000
    3/8"-16
    0.053"0.187"510Acetal
    0.63"Slotted
    000000000000
     

    Press-Fit Ball-Nose Spring Plungers

    Image of Product. Front orientation. Spring Plungers. Press-Fit Ball-Nose Spring Plungers, Flanged Profile, Smooth Body.
    Image of Attribute. Front orientation. Contains Annotated. Press-Fit Ball-Nose Spring Plungers, Flanged Profile.

    Flanged Profile

    Smooth Body

    Flanged Profile

    When you can't tap threads in your mounting surface, push these spring plungers into unthreaded holes. They work well in wood, plastic, and other soft materials that might crack if you try to cut threads. The spring-loaded ball compresses when a part presses against it, and then pops out into a notch or groove to hold the part in place.
    For a snug fit, use an arbor press to install these spring plungers in a slightly smaller hole than the body diameter.
    Flanged Profile—The flanged body stops the spring plunger from sliding back through the hole when the nose compresses under a strong force. It also acts as a gripping tab so you can pull the plunger out to make adjustments.
    420 Stainless Steel Nose—Highly wear resistant, the nose grinds against hard metal surfaces without denting or scratching. However, 420 stainless steel is not quite as corrosion resistant as 316 stainless steel.
    Acetal Nose—The best plastic for damp and wet environments, acetal won't swell or lose strength if exposed to moisture. These noses are extra soft to avoid scratching delicate surfaces. They are best for use on soft materials, such as aluminum.
    Smooth Body—These spring plungers slide effortlessly into unthreaded holes, but don't grip quite as firmly as those with a knurled body.
    Extended Nose Force—This is the amount of force needed to start depressing the nose.
    Compressed Nose Force—This is the amount of force needed to fully depress the nose into the plunger body, so it releases from a hole, notch, or surface. A lighter compressed nose force with a shallower hole releases more easily, while a heavier compressed nose force with a deeper hole holds more securely.
    Nose
    Nose
    Force, lbf
    Body
    Flange
    Extended
    Lg.
    Dia.
    Extended
    Compressed
    Material
    Texture
    Dia.
    Lg.
    Thick.
    Dia.
    Each
    Flanged Profile
     
    420 Stainless Steel Nose
    0.55 mm2 mm0.40.8Acetal
    Smooth3 mm3.4 mm0.6 mm3.6 mm000000000000
    0.8 mm3 mm0.71.3Acetal
    Smooth4 mm4 mm1 mm4.6 mm00000000000
    1 mm4 mm1.32.1Acetal
    Smooth5 mm5 mm1 mm5.6 mm00000000000
    1.6 mm5 mm1.42.8Acetal
    Smooth6 mm6 mm1 mm6.5 mm00000000000
    1.9 mm6.5 mm2.24.6Acetal
    Smooth8 mm8 mm1 mm8.5 mm00000000000
    2.4 mm8 mm2.75Acetal
    Smooth10 mm12 mm1.5 mm11 mm00000000000
    3.3 mm10 mm3.15.6Acetal
    Smooth12 mm14.5 mm1.5 mm13 mm00000000000
     
    Acetal Nose
    0.035"0.093"2518-8 Stainless Steel
    Smooth0.125"0.25"1/32"3/16"00000000000
    0.035"0.093"25SteelSmooth0.125"0.25"1/32"3/16"0000000000
    0.046"0.125"0.8218-8 Stainless Steel
    Smooth0.157"0.33"1/32"3/16"00000000000
    0.046"0.125"1.53.518-8 Stainless Steel
    Smooth0.157"0.33"1/32"3/16"0000000000
    0.046"0.125"1.53.5SteelSmooth0.157"0.33"1/32"3/16"00000000000
    0.046"0.125"37.518-8 Stainless Steel
    Smooth0.157"0.33"1/32"3/16"00000000000
    0.046"0.125"37.5SteelSmooth0.157"0.33"1/32"3/16"00000000000
    0.058"0.156"41018-8 Stainless Steel
    Smooth0.188"0.41"1/32"1/4"00000000000
    0.058"0.156"410SteelSmooth0.188"0.41"1/32"1/4"00000000000
    0.07"0.187"61318-8 Stainless Steel
    Smooth0.25"0.48"3/64"5/16"00000000000
    0.07"0.187"613SteelSmooth0.25"0.48"3/64"5/16"00000000000
    0.09"0.25"81618-8 Stainless Steel
    Smooth0.312"0.64"3/64"3/8"00000000000
    0.09"0.25"816SteelSmooth0.312"0.64"3/64"3/8"00000000000
    0.11"0.312"101818-8 Stainless Steel
    Smooth0.375"0.79"5/64"1/2"00000000000
    0.11"0.312"1018SteelSmooth0.375"0.79"5/64"1/2"00000000000
    0.161"0.437"122318-8 Stainless Steel
    Smooth0.5"1.13"3/32"11/16"00000000000
    0.161"0.437"1223SteelSmooth0.5"1.13"3/32"11/16"00000000000
    0.8 mm3 mm0.71.5Acetal
    Smooth4 mm4 mm1 mm4.6 mm00000000000
    1 mm4 mm1.32.1Acetal
    Smooth5 mm5 mm1 mm5.6 mm00000000000
    1.6 mm5 mm1.42.8Acetal
    Smooth6 mm6 mm1 mm6.5 mm00000000000
    1.9 mm6.5 mm2.24.6Acetal
    Smooth8 mm8 mm1 mm8.5 mm00000000000
    2.4 mm8 mm2.75Acetal
    Smooth10 mm12 mm1.5 mm11 mm00000000000
    3.3 mm10 mm3.15.6Acetal
    Smooth12 mm14.5 mm1.5 mm13 mm00000000000
     
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