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    166 Products

    Surface Plates

    Image of Product. Front orientation. Surface Plates. Rectangular Plate.

    Rectangular Plate

    Image of Product. Front orientation. Surface Plates. Rectangular Plate with Two Ledges.

    Rectangular Plate with Two Ledges

    With flatness tolerances thinner than a strand of hair, these plates give you the flattest possible surface for accurate measurements. They’re typically used as a reference plane to inspect finished products and calibrate precision measuring tools, such as height gauges and dial indicators. Unlike metal plates, these granite plates won’t rust or interfere with nearby electronics. They also won’t warp when temperatures fluctuate. To maintain their flatness and finish, rotate plates regularly and apply granite cleaner (not included) to remove particles without leaving a residue.
    Also Available: Other plate sizes. Please order 2245A999 and specify grade, length, width, thickness, and with or without ledges.
    Laboratory-Grade AA Plate—Best for precision inspections and quality-control work in calibration labs. These plates have the tightest flatness tolerance for the highest level of accuracy.
    Inspection-Grade A Plate—Your go-to for general inspections and quality-control work. These plates are slightly less precise than grade AA plates with double the flatness tolerance.
    Toolroom-Grade B Plate—Suitable for checking routine measurements throughout a shop. These plates are the least precise with four times the flatness tolerance of grade AA plates.
    Rectangular Plate with Two Ledges—Choose these plates if you need to mount fixtures and instruments with a clamp.
    Black—Harder and denser than red plates to handle heavier loads, such as large bearings and other machined parts.
    Surface Plate Covers—Prevent dust and debris from accumulating on plates when you’re not using them.
    Plates
    Surface
    Plate Covers
    Rectangular Plate
    Rectangular Plate
    with Two Ledges
    Flatness
    Tolerance
    Lg.
    Wd.
    Ht.
    Color
    Specs. Met
    Mil. Spec.
    Certificate Type
    Wt.,
    lb.
    Each
    Wt.,
    lb.
    Each
    Each
    Laboratory-Grade AA Plate
     
    Black Granite
    0.00005"6"4"2"BlackASME B89.3.7, ISO 10012Fed. Spec. GGG-P-463Accuracy Certificate Traceable to NIST72245A1010000000———0———0
    0.00005"12"8"2"BlackASME B89.3.7, ISO 10012Fed. Spec. GGG-P-463Accuracy Certificate Traceable to NIST282245A81000000———022455A1010000000
    0.00005"18"12"4"BlackASME B89.3.7, ISO 10012Fed. Spec. GGG-P-463Accuracy Certificate Traceable to NIST932245A39000000832245A72000000022455A6400000
    0.000075"24"18"4"BlackASME B89.3.7, ISO 10012Fed. Spec. GGG-P-463Accuracy Certificate Traceable to NIST1852245A410000001752245A5300000022455A65000000
    0.0001"36"24"6"BlackASME B89.3.7, ISO 10012Fed. Spec. GGG-P-463Accuracy Certificate Traceable to NIST6012245A4200000000———022455A66000000
    0.0002"48"36"6"BlackASME B89.3.7, ISO 10012Fed. Spec. GGG-P-463Accuracy Certificate Traceable to NIST1,2032245A8200000000———022455A67000000
     
    Inspection-Grade A Plate
     
    Black Granite
    0.0001"6"4"2"BlackASME B89.3.7, ISO 10012Fed. Spec. GGG-P-463Accuracy Certificate Traceable to NIST72245A102000000———0———0
    0.0001"12"8"2"BlackASME B89.3.7, ISO 10012Fed. Spec. GGG-P-463Accuracy Certificate Traceable to NIST282245A83000000———022455A101000000
    0.0001"18"12"4"BlackASME B89.3.7, ISO 10012Fed. Spec. GGG-P-463Accuracy Certificate Traceable to NIST932245A43000000832245A4600000022455A6400000
    0.00015"24"18"4"BlackASME B89.3.7, ISO 10012Fed. Spec. GGG-P-463Accuracy Certificate Traceable to NIST1852245A440000001752245A4700000022455A65000000
    0.0002"36"24"6"BlackASME B89.3.7, ISO 10012Fed. Spec. GGG-P-463Accuracy Certificate Traceable to NIST5552245A45000000005302245A480000000022455A66000000
    0.0004"48"36"6"BlackASME B89.3.7, ISO 10012Fed. Spec. GGG-P-463Accuracy Certificate Traceable to NIST1,1102245A56000000001,0632245A490000000022455A67000000
     
    Toolroom-Grade B Plate
     
    Black Granite
    0.0002"6"4"2"BlackASME B89.3.7, ISO 10012Fed. Spec. GGG-P-463Accuracy Certificate Traceable to NIST72245A103000000———0———0
    0.0002"12"8"2"BlackASME B89.3.7, ISO 10012Fed. Spec. GGG-P-463Accuracy Certificate Traceable to NIST212245A23000000———022455A101000000
    0.0002"18"12"3"BlackASME B89.3.7, ISO 10012Fed. Spec. GGG-P-463Accuracy Certificate Traceable to NIST702245A24000000662245A6200000022455A6400000
    0.0003"24"18"3"BlackASME B89.3.7, ISO 10012Fed. Spec. GGG-P-463Accuracy Certificate Traceable to NIST1392245A210000001302245A6300000022455A65000000
    0.0004"36"24"4"BlackASME B89.3.7, ISO 10012Fed. Spec. GGG-P-463Accuracy Certificate Traceable to NIST3702245A260000003572245A6400000022455A66000000
    0.0008"48"36"6"BlackASME B89.3.7, ISO 10012Fed. Spec. GGG-P-463Accuracy Certificate Traceable to NIST1,2032245A3800000000———022455A67000000
     
    Surface Plate Stands

    Polishing Stones for Steel

    Just the right hardness level for polishing steel tools, molds, and dies. These stones also double as a good choice for general polishing. Choose the stone shape that best matches the contour of your work surface. These stones can be used by hand or in a power tool with a holder (both sold separately). To keep debris from building up, apply a water-soluble or oil-based lubricant during use.
    Straight Square
    Image of Product. Front orientation. ZoomedIn view. Polishing Stones. Polishing Stones for Steel, Straight Square.
    Silicon Carbide Abrasive—Silicon carbide stones, also known as Crystolon stones, are extremely sharp. These stones remove material more quickly than aluminum oxide stones. They are best for the early polishing stage when you want to clear away more material from your work surface. However, they give you less control over material removal than aluminum oxide stones, so stopping at an exact point is more difficult to do.
    Lg.
    Wd.
    Thk.
    Color
    Lubrication
    Each
    Silicon Carbide—For Steel
     
    100 Grit (For Smooth Finish)
    6"1/4"1/4"BlackRequired47465A22100000
    6"1/2"1/2"BlackRequired47465A2270000
     
    150 Grit (For Smooth Finish)
    6"1/4"1/4"BlackRequired47465A2220000
    6"1/2"1/2"BlackRequired47465A2280000
     
    220 Grit (For Smooth Finish)
    6"1/4"1/4"BlackRequired47465A2230000
    6"1/2"1/2"BlackRequired47465A2290000
     
    280 Grit (For Extra-Smooth Finish)
    4"1/4"1/4"BlackRequired4345A210000
    4"3/8"3/8"BlackRequired4345A230000
     
    320 Grit (For Extra-Smooth Finish)
    6"1/4"1/4"BlackRequired47465A2240000
    6"1/2"1/2"BlackRequired47465A2310000
     
    400 Grit (For Extra-Smooth Finish)
    6"1/4"1/4"BlackRequired47465A2250000
    6"1/2"1/2"BlackRequired47465A2320000
     
    600 Grit (For Polished Finish)
    6"1/4"1/4"BlackRequired47465A2260000
    6"1/2"1/2"BlackRequired47465A23300000
     
    800 Grit (For Polished Finish)
    6"1/4"1/4"BlackRequired47465A2710000
    6"1/2"1/2"BlackRequired47465A27200000
     
    Accessories for Polishing Stones
    Straight Triangular
    Image of Product. Front orientation. Polishing Stones. Polishing Stones for Steel, Straight Triangular.
    Silicon Carbide Abrasive—Silicon carbide stones, also known as Crystolon stones, are extremely sharp. These stones remove material more quickly than aluminum oxide stones. They are best for the early polishing stage when you want to clear away more material from your work surface. However, they give you less control over material removal than aluminum oxide stones, so stopping at an exact point is more difficult to do.
    Lg.
    Wd.
    Color
    Lubrication
    Each
    Silicon Carbide—For Steel
     
    280 Grit (For Extra-Smooth Finish)
    4"1/4"BlackRequired4346A11000000
    4"3/8"BlackRequired4346A1300000
    4"1/2"BlackRequired4346A1500000
     
    Straight Round
    Image of Product. Front orientation. Polishing Stones. Polishing Stones for Steel, Straight Round.
    Silicon Carbide Abrasive—Silicon carbide stones, also known as Crystolon stones, are extremely sharp. These stones remove material more quickly than aluminum oxide stones. They are best for the early polishing stage when you want to clear away more material from your work surface. However, they give you less control over material removal than aluminum oxide stones, so stopping at an exact point is more difficult to do.
    Lg.
    Dia.
    Color
    Lubrication
    Each
    Silicon Carbide—For Steel
     
    100 Grit (For Smooth Finish)
    6"1/4"BlackRequired47465A24100000
     
    150 Grit (For Smooth Finish)
    6"1/4"BlackRequired47465A2420000
     
    220 Grit (For Smooth Finish)
    6"1/4"BlackRequired47465A2430000
     
    280 Grit (For Extra-Smooth Finish)
    4"3/8"BlackRequired4347A4300000
    4"1/2"BlackRequired4347A4500000
     
    320 Grit (For Extra-Smooth Finish)
    6"1/4"BlackRequired47465A2440000
     
    400 Grit (For Extra-Smooth Finish)
    6"1/4"BlackRequired47465A2450000
     
    600 Grit (For Polished Finish)
    6"1/4"BlackRequired47465A2460000
     
    Hand-Held Stone Holders
    Straight Rectangular
    Image of Product. Front orientation. ZoomedIn view. Polishing Stones. Polishing Stones for Steel, Straight Rectangular.
    Silicon Carbide Abrasive—Silicon carbide stones, also known as Crystolon stones, are extremely sharp. These stones remove material more quickly than aluminum oxide stones. They are best for the early polishing stage when you want to clear away more material from your work surface. However, they give you less control over material removal than aluminum oxide stones, so stopping at an exact point is more difficult to do.
    Lg.
    Wd.
    Thk.
    Color
    Lubrication
    Each
    Silicon Carbide—For Steel
     
    100 Grit (For Smooth Finish)
    6"1/2"1/4"BlackRequired47465A23400000
     
    150 Grit (For Smooth Finish)
    6"1/2"1/4"BlackRequired47465A2350000
    6"1"1/2"BlackRequired47465A2740000
     
    220 Grit (For Smooth Finish)
    6"1/2"1/4"BlackRequired47465A2360000
    6"1"1/2"BlackRequired47465A2750000
     
    320 Grit (For Extra-Smooth Finish)
    6"1/2"1/4"BlackRequired47465A2370000
    6"1"1/2"BlackRequired47465A2760000
     
    400 Grit (For Extra-Smooth Finish)
    6"1/2"1/4"BlackRequired47465A2380000
    6"1"1/2"BlackRequired47465A2770000
     
    600 Grit (For Polished Finish)
    6"1/2"1/4"BlackRequired47465A2390000
    6"1"1/2"BlackRequired47465A27800000
     
    800 Grit (For Polished Finish)
    6"1/2"1/4"BlackRequired47465A2730000
    6"1"1/2"BlackRequired47465A27900000
     
    Accessories for Polishing Stones

    Detail Polishing Stones

    Smooth ribs, slots, teeth, and other fine features—these stones are thin enough to slip into hard-to-reach areas. Made of bonded ceramic, they’re harder and more wear resistant than aluminum oxide stones, but flexible enough not to crack under pressure. Pair with a holder (sold separately) to polish by hand or with a power tool, such as an ultrasonic polisher. Apply a water-soluble or oil-based lubricant to help keep debris from building up on the surface.
    Straight Round
    Image of Product. Front orientation. ZoomedIn view. Polishing Stones. Detail Polishing Stones, Straight Round.
    Image of Product. Front orientation. Polishing Stones. Detail Polishing Stones, Straight Round.
    Ceramic/Diamond Blend Abrasive—Ceramic/diamond stones have diamond particles spread throughout the ceramic to make them harder and sharper. They won’t wear out as quickly as plain ceramic stones when finishing hardened steel, carbide, and other extremely hard materials.
    Dia.
    Lg.
    Color
    Each
    Ceramic—For Aluminum, Brass, Bronze, Copper, Iron, Nickel, Steel, Stainless Steel, and Titanium
     
    600 Grit (For Polished Finish)
    1/8"2"Black47465A725000000
     
    Ceramic/Diamond Blend—For Carbide, Iron, Nickel, Steel, Stainless Steel, Titanium, and Hardened Steel
     
    180 Grit (For Smooth Finish)
    1/8"2"Black9567N2400000
     
    Accessories for Polishing Stones
    Straight Rectangular
    Image of Product. Front orientation. Polishing Stones. Detail Polishing Stones, Straight Rectangular.
    Image of Product. Front orientation. ZoomedIn view. Polishing Stones. Detail Polishing Stones, Straight Rectangular.
    Ceramic/Diamond Blend Abrasive—Ceramic/diamond stones have diamond particles spread throughout the ceramic to make them harder and sharper. They won’t wear out as quickly as plain ceramic stones when finishing hardened steel, carbide, and other extremely hard materials.
    Lg.
    Wd.
    Thk.
    Color
    Each
    Ceramic—For Aluminum, Brass, Bronze, Copper, Iron, Nickel, Steel, Stainless Steel, and Titanium
     
    600 Grit (For Polished Finish)
    4"5/64"1/64"Black47465A685000000
    4"5/64"3/64"Black47465A70500000
    4"5/32"1/64"Black47465A69500000
    4"5/32"3/64"Black47465A71500000
    4"15/64"1/64"Black47465A67500000
    4"15/64"3/64"Black47465A67800000
    4"25/64"3/64"Black47465A72200000
     
    Ceramic/Diamond Blend—For Carbide, Iron, Nickel, Steel, Stainless Steel, Titanium, and Hardened Steel
     
    180 Grit (For Smooth Finish)
    4"5/32"3/64"Black9567N1100000
    4"15/64"3/64"Black9567N1500000
    4"25/64"3/64"Black9567N1900000
     
    Accessories for Polishing Stones

    Clog-Resistant Polishing Stones for Steel

    No need to stop and clean these stones as you polish—they’re filled with oil to keep debris from getting stuck in the pores. Use a holder to polish by hand or with a power tool (both sold separately). You’ll also need a water-soluble or oil-based lubricant to wash away debris and reduce friction and heat on your workpiece.
    Straight Square
    Image of Product. Front orientation. Polishing Stones. Clog-Resistant Polishing Stones for Steel, Straight Square.
    Image of Product. Front orientation. ZoomedIn view. Polishing Stones. Clog-Resistant Polishing Stones for Steel, Straight Square.
    Silicon Carbide Abrasive—Silicon carbide stones, also known as Crystolon stones, are extremely sharp. These stones remove material more quickly than aluminum oxide stones. They are best for the early polishing stage when you want to clear away more material from your work surface. However, they give you less control over material removal than aluminum oxide stones, so stopping at an exact point is more difficult to do.
    Lg.
    Wd.
    Thk.
    Color
    Lubrication
    Each
    Silicon Carbide—For Steel
     
    280 Grit (For Extra-Smooth Finish)
    4"1/2"1/2"BlackLubricated, Required4345A25000000
     
    Straight Round
    Image of Product. Front orientation. Polishing Stones. Clog-Resistant Polishing Stones for Steel, Straight Round.
    Image of Product. Front orientation. ZoomedIn view. Polishing Stones. Clog-Resistant Polishing Stones for Steel, Straight Round.
    Silicon Carbide Abrasive—Silicon carbide stones, also known as Crystolon stones, are extremely sharp. These stones remove material more quickly than aluminum oxide stones. They are best for the early polishing stage when you want to clear away more material from your work surface. However, they give you less control over material removal than aluminum oxide stones, so stopping at an exact point is more difficult to do.
    Lg.
    Dia.
    Color
    Lubrication
    Each
    Silicon Carbide—For Steel
     
    280 Grit (For Extra-Smooth Finish)
    4"1/4"BlackLubricated, Required4347A41000000
     
    Hand-Held Stone Holders

    Polishing Stone Assortments for Steel

    Image of Product. Front orientation. Polishing Stones. Polishing Stone Assortments for Steel.
    Keep stones of different grits on hand for each step of polishing steel tools, molds, and dies. The polishing stones in these assortments are the most common choice for general polishing. These stones can be used by hand or in a power tool with a holder (both sold separately). To keep debris from building up, apply a water-soluble or oil-based lubricant during use.
    Silicon Carbide Abrasive—Silicon carbide stones, also known as Crystolon stones, are extremely sharp. These stones remove material more quickly than aluminum oxide stones. They are best for the early polishing stage when you want to clear away more material from your work surface. However, they give you less control over material removal than aluminum oxide stones, so stopping at an exact point is more difficult to do.
    No. of
    Pieces
    Includes
    Color
    Each
    Silicon Carbide—For Steel
    5One each 150, 220, 320, 400, 600-grit Stones—6" Lg. × 1/2" Wd. × 1/8" Thick.Black9101N14000000
    5One each 150, 220, 320, 400, 600-grit Stones—6" Lg. × 1/2" Wd. × 1/4" Thick.Black9101N1500000
    5One each 150, 220, 320, 400, 600-grit Stones—6" Lg. × 1" Wd. × 1/4" Thick.Black9101N1600000
    7One each 100, 150, 180, 220, 320, 400, 600-grit Stones—6" Lg. × 1/2" Wd. × 1/8" Thick.Black9101N1900000
    12One each 220, 320, 400, 600-grit Stones—6" Lg. × 1/4" Wd. × 1/8" Thick.
    One each 220, 320, 400, 600-grit Stones—6" Lg. × 1/2" Wd. × 1/8" Thick.
    One each 220, 320, 400, 600-grit Stones—6" Lg. × 1/2" Wd. × 1/4" Thick.
    Black9101N1800000
     
    Accessories for Polishing Stones

    Miniature Detail Polishing Stone Assortments

    Image of ProductInUse. Front orientation. ZoomedIn view. Polishing Stones. Miniature Detail Polishing Stone Assortments.
    Image of Product. Front orientation. Polishing Stones. Miniature Detail Polishing Stone Assortments.
    Keep stones of different grits on hand to handle every stage of polishing on the smallest ribs, slots, and crevices. These stones are as thin as pencil lead, but stronger than they appear—made of bonded ceramic, they are tough yet flexible. They won’t snap like lead when you apply pressure. These stones also resist wear, so they last a long time. Pair them with a holder to polish by hand or with an ultrasonic polisher (sold separately). To keep debris from building up, apply a water-soluble or oil-based lubricant during use.
    No. of
    Pieces
    Includes
    Color
    Each
    Ceramic—For Aluminum, Brass, Bronze, Copper, Iron, Nickel, Steel, Stainless Steel, and Titanium
    5One 1/32" Wd. Hand-Held Stone Holder
    One each 120, 320, 600, 1200-grit Stones—2" Lg. × 1/32" (0.900 mm) Wd. × 1/32" (0.900 mm) Thick.
    Black, Brown, Green, Red9659N44000000
     
    Accessories and Replacements for Polishing Stones

    Detail Polishing Stone Assortments

    Keep stones in different grits on hand to smooth ribs, slots, teeth, and other fine features. The stones in these assortments are thin enough to slip into hard-to-reach areas. Made of bonded ceramic, they’re harder and more wear resistant than aluminum oxide stones, but flexible enough not to crack under pressure. Pair these stones with a holder to polish by hand or with a power tool, such as an ultrasonic polisher. Some holders are sold separately. Apply a water-soluble or oil-based lubricant to help keep debris from building up on the surface.
    Straight Rectangular
    Image of Product. Front orientation. Polishing Stones. Detail Polishing Stone Assortments, Straight Rectangular.
    Image of Product. Front orientation. ZoomedIn view. Polishing Stones. Detail Polishing Stone Assortments, Straight Rectangular.
    Ceramic/Diamond Blend Abrasive—Ceramic/diamond stones have diamond particles spread throughout the ceramic to make them harder and sharper. They won’t wear out as quickly as plain ceramic stones when finishing hardened steel, carbide, and other extremely hard materials.
    No. of
    Pieces
    Includes
    Color
    Each
    Ceramic/Diamond Blend—For Carbide and Hardened Steel
    3One each 180, 400, 800-grit Stone—4" Lg. × 5/32" Wd. × 3/64" Thick.Black, Blue, Gray9631N71000000
     
    Accessories for Polishing Stones

    Belt Sanding Sticks

    Access tight spots. These sticks are spring-loaded to hold a small sanding belt taut, but you can easily rotate the belt when it becomes worn. They’re color coded by grit to keep you organized. All sticks accept belts of the same width regardless of grit.
    Sold Individually
    Image of Product. Front orientation. Sanding Sticks and Bricks. Belt Sanding Sticks, Sold Individually.
    For
    Belt
    Grit
    Color
    Wd.
    Lg.
    Wd.
    Lg.
    Abrasive
    Material
    Includes
    Each
    For Polished Finish
    600Black1/4"12 3/4"1/4"6 1/4"Aluminum OxideOne Sanding Belt
    One Sanding Stick
    9185N1600000
    600Black1/2"16"1/2"8"Aluminum OxideOne Sanding Belt
    One Sanding Stick
    9185N230000
     
    Belts
    Sold as Sets
    Image of Product. Front orientation. Sanding Sticks and Bricks. Belt Sanding Sticks, Sold as Sets.
    For
    Belt
    Grit
    Color
    Wd.
    Lg.
    Wd.
    Lg.
    Abrasive
    Material
    Includes
    Each
    For Extra-Smooth and Polished Finish
    240, 320, 400, 500Blue, Green, Yellow, Black1/4"12 3/4"1/4"6 1/4"Aluminum OxideSix Sanding Belts of Each Grit
    One Sanding Stick of Each Grit
    9184N12000000
     
    Belts

    Miniature Detail Polishing Stones

    About the size of pencil lead, these stones polish your smallest ribs, slots, and crevices in molds and dies. Don’t underestimate their thin profile—they’re made of bonded ceramic, which makes them tough yet flexible. This means they won’t snap like pencil lead does when you apply pressure during polishing. These stones also resist wear, so they last a long time. Pair them with a holder to polish by hand or with an ultrasonic polisher (both sold separately). Apply a water-soluble or oil-based lubricant to help keep debris from building up on the surface.
    Straight Square
    Image of Product. Front orientation. ZoomedIn view. Polishing Stones. Miniature Detail Polishing Stones.
    Image of Product. Front orientation. Polishing Stones. Miniature Detail Polishing Stones.
    Grit
    For
    Finish
    Lg.
    Wd.
    Thk.
    Color
    Lubrication
    Each
    Ceramic—For Aluminum, Brass, Bronze, Copper, Iron, Nickel, Steel, Stainless Steel, and Titanium
    600Polished2"1/32"/0.9 mm1/32"/0.9 mmBlackNot Required9649N2700000
     
    Accessories for Polishing Stones
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