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    71 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.
    Red—Resist wear better than black plates to last up to five times longer. With a higher percentage of quartz, you can slide parts across these plates without worrying about nicks and scratches.
    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
    Certificate Type
    Wt.,
    lb.
    Each
    Wt.,
    lb.
    Each
    Each
    Laboratory-Grade AA Plate
     
    Black Granite
    0.00005"6"4"2"BlackASME B89.3.7, Fed. Spec. GGG-P-463, ISO 10012Accuracy Certificate Traceable to NIST7000000000000000———0———0
    0.00005"12"8"2"BlackASME B89.3.7, Fed. Spec. GGG-P-463, ISO 10012Accuracy Certificate Traceable to NIST280000000000000———00000000000000000
    0.00005"18"12"4"BlackASME B89.3.7, Fed. Spec. GGG-P-463, ISO 10012Accuracy Certificate Traceable to NIST93000000000000083000000000000000000000000000
    0.000075"24"18"4"BlackASME B89.3.7, Fed. Spec. GGG-P-463, ISO 10012Accuracy Certificate Traceable to NIST1850000000000000175000000000000000000000000000
    0.0001"36"24"6"BlackASME B89.3.7, Fed. Spec. GGG-P-463, ISO 10012Accuracy Certificate Traceable to NIST601000000000000000———000000000000000
    0.0002"48"36"6"BlackASME B89.3.7, Fed. Spec. GGG-P-463, ISO 10012Accuracy Certificate Traceable to NIST1,203000000000000000———000000000000000
     
    Granite
    0.00005"18"12"4"RedASME B89.3.7, Fed. Spec. GGG-P-463Accuracy Certificate Traceable to NIST840000000000000000———00000000000000
    0.000075"24"18"4"RedASME B89.3.7, Fed. Spec. GGG-P-463Accuracy Certificate Traceable to NIST1680000000000000000———000000000000000
     
    Inspection-Grade A Plate
     
    Black Granite
    0.0001"6"4"2"BlackASME B89.3.7, Fed. Spec. GGG-P-463, ISO 10012Accuracy Certificate Traceable to NIST700000000000000———0———0
    0.0001"12"8"2"BlackASME B89.3.7, Fed. Spec. GGG-P-463, ISO 10012Accuracy Certificate Traceable to NIST280000000000000———0000000000000000
    0.0001"18"12"4"BlackASME B89.3.7, Fed. Spec. GGG-P-463, ISO 10012Accuracy Certificate Traceable to NIST9300000000000008300000000000000000000000000
    0.00015"24"18"4"BlackASME B89.3.7, Fed. Spec. GGG-P-463, ISO 10012Accuracy Certificate Traceable to NIST1850000000000000175000000000000000000000000000
    0.0002"36"24"6"BlackASME B89.3.7, Fed. Spec. GGG-P-463, ISO 10012Accuracy Certificate Traceable to NIST55500000000000000053000000000000000000000000000000
    0.0004"48"36"6"BlackASME B89.3.7, Fed. Spec. GGG-P-463, ISO 10012Accuracy Certificate Traceable to NIST1,1100000000000000001,06300000000000000000000000000000
     
    Granite
    0.0001"12"8"2"RedASME B89.3.7, Fed. Spec. GGG-P-463Accuracy Certificate Traceable to NIST2000000000000000———0000000000000000
     
    Toolroom-Grade B Plate
     
    Black Granite
    0.0002"6"4"2"BlackASME B89.3.7, Fed. Spec. GGG-P-463, ISO 10012Accuracy Certificate Traceable to NIST700000000000000———0———0
    0.0002"12"8"2"BlackASME B89.3.7, Fed. Spec. GGG-P-463, ISO 10012Accuracy Certificate Traceable to NIST210000000000000———0000000000000000
    0.0002"18"12"3"BlackASME B89.3.7, Fed. Spec. GGG-P-463, ISO 10012Accuracy Certificate Traceable to NIST7000000000000006600000000000000000000000000
    0.0003"24"18"3"BlackASME B89.3.7, Fed. Spec. GGG-P-463, ISO 10012Accuracy Certificate Traceable to NIST1390000000000000130000000000000000000000000000
    0.0004"36"24"4"BlackASME B89.3.7, Fed. Spec. GGG-P-463, ISO 10012Accuracy Certificate Traceable to NIST3700000000000000357000000000000000000000000000
    0.0008"48"36"6"BlackASME B89.3.7, Fed. Spec. GGG-P-463, ISO 10012Accuracy Certificate Traceable to NIST1,203000000000000000———000000000000000
     
    Surface Plate Stands

    Granite Surface Plate Stands

    Image of Product. Front orientation. Mobile. Mobile.

    Mobile

    Image of Product. Front orientation. Surface Plate Stands. Stationary.

    Stationary

    Secure granite surface plates on these stands to ensure a flat surface for accurate measurements. To keep plates from sagging and warping, stands attach to plates at three support points, as specified in Fed. Spec. GGG-P-463c. The welded steel construction offers greater strength, durability, and stability than economical alternatives such as block and wedge systems.
    Mobile—Conduct measuring and inspecting tasks anywhere in your facility. With steel plate casters and hard, durable wheels, these stands support the same capacities as their stationary counterparts. Turn the adjustable screws on top of the stand to level the plate on uneven floors.
    Stationary—Create a permanent setup for routine measurements and inspections. Twist the mounts at the bottom of each leg to level the plate, even on uneven floors.
    For
    Plate
    For
    Rectangular Plates
    For Rectangular Plates
    with Two Ledges
    Lg.
    Wd.
    Ht.
    Load Cap.,
    lb.
    Ht.
    Material
    Each
    Each
    Mobile
    18"12"3", 4"40036"Painted Steel000000000000000000000000000000
    24"18"3", 4"50036"Painted Steel0000000000000000000000000000
    36"24"4", 6"1,20036"Painted Steel00000000000000000000000000000000
    48"36"6"2,40036"Painted Steel00000000000000000000000000000000
     
    Stationary
    18"12"3", 4"40036"Painted Steel0000000000000000000000000000
    24"18"3", 4"50036"Painted Steel0000000000000000000000000000
    36"24"4", 6"1,20036"Painted Steel0000000000000000000000000000
    48"36"6"2,40036"Painted Steel0000000000000000000000000000
     

    Economy Rigid-Arm Weighted-Base Variance Indicator Holders

    Image of Product. With Standard Arm. Front orientation. Variance Indicator Holders. Economy Rigid-Arm Weighted-Base Variance Indicator Holders.
    Image of Product. With Fine-Adjustment Arm. Front orientation. Variance Indicator Holders. Economy Rigid-Arm Weighted-Base Variance Indicator Holders, Fine-Adjustment Arm.

    With Standard Arm

    With

    Fine-Adjustment Arm

    Commonly used on workbenches, these stands have a heavy granite base for stability. They hold indicators in place for taking accurate readings.
    Fine-Adjustment Arm—Holders with a fine-adjustment arm have a knob you can use to precisely position the arm and your indicator. They give you more control over your work setup than holders with a standard arm.
    Base
    Upright
    Post
    Arm
    For Mounting
    Lug Hole Dia.
    For Mounting
    Stem Dia.
    Surface
    Accuracy
    Throat
    Dp.
    Type
    Lg.
    Wd.
    Ht.
    Thread Size
    Material
    Dia.
    Ht.
    Material
    Lg.
    Type
    Each
    Stem Mount
    3/8"±0.00025"2 3/8"Flat6"6"2"3/8"-16
    Granite1 1/4"8"Stainless Steel
    4 1/8"Rigid000000000000000
    3/8"±0.00025"4 25/32"Flat12"18"4"3/8"-16
    Granite1 1/4"12"Stainless Steel
    6 9/16"Rigid00000000000000
    3/8"±0.00025"5 5/8"Flat8"12"2"3/8"-16
    Granite1 1/4"12"Stainless Steel
    7 3/8"Rigid00000000000000
     
    Lug Mount
     
    Variance Indicator Holders
    1/4"±0.00025"2 3/8"Flat6"6"2"3/8"-16
    Granite1 1/4"8"Steel4 1/8"Rigid00000000000000
     
    Fine-Adjustment Arm
    1/4"±0.00005"4 3/4"Flat12"9"2"M12 x 1.25 mmGranite1 1/4"12"Steel7 1/4"Rigid00000000000000
    1/4"±0.00005"4 3/4"Flat18"12"3"M12 x 1.25 mmGranite1 1/4"12"Steel7 1/4"Rigid00000000000000
    1/4"±0.0005"2 3/8"Flat6"6"2"M10 x 1.5 mmGranite1"8"Steel1 7/8"Rigid00000000000000
     

    Granite Surface Plate Cleaners

    Image of Product. Front orientation. Surface Plate Cleaners. Granite Surface Plate Cleaners, Spray Bottle.
    Image of Product. Front orientation. Surface Plate Cleaners. Granite Surface Plate Cleaners, Bottle.
    Image of Product. Jug. Front orientation. Surface Plate Cleaners. Granite Surface Plate Cleaners, Jug.

    Spray

    Bottle

    Bottle

    Jug

    Remove particles from granite surface plates without leaving a residue.
    Container
    Type
    Size
    Solution
    Type
    Harshness
    For Use
    On
    For Removing
    Each
    Liquid Concentrates
    Spray Bottle16 fl. oz.Water BasedModerateStoneDirt, Grease, Oil000000000000
    Bottle32 fl. oz.Water BasedModerateStoneDirt, Grease, Oil00000000000
    Jug1 gal.Water BasedModerateStoneDirt, Grease, Oil000000000000
     

    Economy Flexible-Arm Weighted-Base Variance Indicator Holders

    Image of Product. With Granite Base. Front orientation. Variance Indicator Holders. Economy Flexible-Arm Weighted-Base Variance Indicator Holders, Fine-Adjustment Clamp , Flat Base.

    With Granite Base

    Adjust the flexible ball-and-socket segmented arm to nearly any position and lock in place. A heavy base adds stability.
    Granite—Holders with a granite base have an extremely tight flatness tolerance. Their flatness gives you an accurate reference for inspection work and lets you move workpieces in and out smoothly. These holders have a fine-adjustment clamp to position indicators at precise angles.
    Base
    Upright
    Post
    Arm
    For Mounting
    Stem Dia.
    Type
    Lg.
    Wd.
    Ht.
    Thread
    Size
    Material
    Dia.
    Ht.
    Lg.
    Dia.
    Type
    Each
    Dovetail and Stem Mount
     
    Fine-Adjustment Clamp
    5/8"Flat9"12"2"5/16"-24
    Granite5/8"12"12"0.625"Flexible00000000000000
    5/8"Flat12"18"3"5/16"-24
    Granite5/8"12"15"0.625"Flexible0000000000000
     

    Economy Jointed-Arm Weighted-Base Variance Indicator Holders

    Image of Product. Front orientation. Variance Indicator Holders. Economy Jointed-Arm Weighted-Base Variance Indicator Holders.
    Stabilize and precisely position your indicator with these weighted bases. Attached to the base, these holders have a jointed arm for moving your indicator up and down and in and out. Tighten the knob on the arm to lock it in place and use the fine-adjustment clamp for angling your indicator just right. Made of granite, the base has an extremely tight flatness tolerance, so it creates an accurate reference point for inspection work. It also means you can easily slide your workpiece in and out.
    Base
    Arm
    For Mounting
    Stem Dia.
    Type
    Lg.
    Wd.
    Ht.
    Thread
    Size
    Material
    Lg.
    Dia.
    Type
    Granite Base Flatness
    Tolerance
    Each
    Dovetail and Stem Mount
     
    Fine-Adjustment Arm, Fine-Adjustment Clamp
    8 mm, 3/8"Flat12"9"2"5/16"-18
    Granite12 1/2"0.495"Jointed-0.00015" to 0.00015"00000000000000
    8 mm, 3/8"Flat18"12"3"5/16"-18
    Granite14"0.495"Jointed-0.00015" to 0.00015"0000000000000
     

    Precision Weighted-Base Variance Indicator Holders

    Image of Product. With Rigid Arm. Front orientation. Variance Indicator Holders. Precision Weighted-Base Variance Indicator Holders.
    Image of Product. With Jointed Arm. Front orientation. Variance Indicator Holders. Precision Weighted-Base Variance Indicator Holders, Fine-Adjustment Arm.

    With Rigid Arm

    With Jointed Arm

    These holders come with a certificate of accuracy traceable to NIST stating that the granite base has passed a test for surface accuracy. The extremely tight flatness tolerances of the granite allow for nearly frictionless workpiece movement and provide an accurate reference plane for inspection work.
    Jointed Arm—Holders with jointed arm have a fine-adjustment knob for precise positioning.
    Base
    Upright
    Post
    Arm
    For Mounting
    Lug Hole Dia.
    For Mounting
    Stem Dia.
    Surface
    Accuracy
    Throat
    Dp.
    Lg.
    Wd.
    Ht.
    Thread
    Size
    Material
    Dia.
    Ht.
    Material
    Lg.
    Type
    Features
    Each
    Stem Mount
    3/8"±0.00005"1 3/4"6"6"2"1/2"-13
    Granite1 1/4"8"Steel4 1/8"Rigid00000000000000
    3/8"±0.0001"5"8"12"2"1/2"-13
    Granite1 1/4"12"Steel7 5/16"JointedFine-Adjustment Arm0000000000000
    3/8"±0.0001"5"12"18"4"1/2"-13
    Granite1 1/4"12"Steel7 5/16"JointedFine-Adjustment Arm0000000000000
     
    Lug Mount
    1/4"±0.00005"1 3/4"6"6"2"1/2"-13
    Granite1 1/4"8"Steel4 1/8"Rigid0000000000000
    1/4"±0.0001"5"8"12"2"1/2"-13
    Granite1 1/4"12"Steel7 5/16"JointedFine-Adjustment Arm0000000000000
    1/4"±0.0001"5"12"18"4"1/2"-13
    Granite1 1/4"12"Steel7 5/16"JointedFine-Adjustment Arm0000000000000
     
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