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    64 Products

    Granite Surface Plates

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

    Rectangular Plate

    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.
    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.
    Rectangular Plate with Two Ledges—Choose these plates if you need to mount fixtures and instruments with a clamp.
    Surface Plate Covers—Prevent dust and debris from accumulating on plates when you’re not using them.
    Surface Plate Stands—Attach to plates at three support points to keep them from sagging and warping, as specified in Fed. Spec. GGG-P-463-c. The welded steel construction offers greater strength, durability, and stability than economical alternatives such as block and wedge systems.
    Plates
    Surface
    Plate Covers
    Rectangular Plate
    Rectangular Plate
    with Two Ledges
    Flatness
    Tolerance
    Lg.
    Wd.
    Ht.
    Specs. Met
    Certificate Type
    Wt.,
    lb.
    Each
    Wt.,
    lb.
    Each
    Each
    Laboratory-Grade AA Plate
     
    Black
    0.00005"6"4"2"ASME B89.3.7, Fed. Spec. GGG-P-463, ISO 10012Accuracy Certificate Traceable to NIST7000000000000000———0———0
    0.00005"12"8"2"ASME B89.3.7, Fed. Spec. GGG-P-463, ISO 10012Accuracy Certificate Traceable to NIST280000000000000———00000000000000000
    0.00005"18"12"4"ASME B89.3.7, Fed. Spec. GGG-P-463, ISO 10012Accuracy Certificate Traceable to NIST93000000000000083000000000000000000000000000
    0.000075"24"18"4"ASME B89.3.7, Fed. Spec. GGG-P-463, ISO 10012Accuracy Certificate Traceable to NIST1850000000000000175000000000000000000000000000
    0.0001"36"24"6"ASME B89.3.7, Fed. Spec. GGG-P-463, ISO 10012Accuracy Certificate Traceable to NIST601000000000000000———000000000000000
    0.0002"48"36"6"ASME B89.3.7, Fed. Spec. GGG-P-463, ISO 10012Accuracy Certificate Traceable to NIST1,203000000000000000———000000000000000
     
    Red
    0.00005"18"12"4"ASME B89.3.7, Fed. Spec. GGG-P-463Accuracy Certificate Traceable to NIST840000000000000000———00000000000000
    0.000075"24"18"4"ASME B89.3.7, Fed. Spec. GGG-P-463Accuracy Certificate Traceable to NIST1680000000000000000———000000000000000
     
    Inspection-Grade A Plate
     
    Black
    0.0001"6"4"2"ASME B89.3.7, Fed. Spec. GGG-P-463, ISO 10012Accuracy Certificate Traceable to NIST700000000000000———0———0
    0.0001"12"8"2"ASME B89.3.7, Fed. Spec. GGG-P-463, ISO 10012Accuracy Certificate Traceable to NIST280000000000000———0000000000000000
    0.0001"18"12"4"ASME B89.3.7, Fed. Spec. GGG-P-463, ISO 10012Accuracy Certificate Traceable to NIST9300000000000008300000000000000000000000000
    0.00015"24"18"4"ASME B89.3.7, Fed. Spec. GGG-P-463, ISO 10012Accuracy Certificate Traceable to NIST1850000000000000175000000000000000000000000000
    0.0002"36"24"6"ASME B89.3.7, Fed. Spec. GGG-P-463, ISO 10012Accuracy Certificate Traceable to NIST55500000000000000053000000000000000000000000000000
    0.0004"48"36"6"ASME B89.3.7, Fed. Spec. GGG-P-463, ISO 10012Accuracy Certificate Traceable to NIST1,1100000000000000001,06300000000000000000000000000000
     
    Red
    0.0001"12"8"2"ASME B89.3.7, Fed. Spec. GGG-P-463Accuracy Certificate Traceable to NIST2000000000000000———0000000000000000
     
    Toolroom-Grade B Plate
     
    Black
    0.0002"6"4"2"ASME B89.3.7, Fed. Spec. GGG-P-463, ISO 10012Accuracy Certificate Traceable to NIST700000000000000———0———0
    0.0002"12"8"2"ASME B89.3.7, Fed. Spec. GGG-P-463, ISO 10012Accuracy Certificate Traceable to NIST210000000000000———0000000000000000
    0.0002"18"12"3"ASME B89.3.7, Fed. Spec. GGG-P-463, ISO 10012Accuracy Certificate Traceable to NIST7000000000000006600000000000000000000000000
    0.0003"24"18"3"ASME B89.3.7, Fed. Spec. GGG-P-463, ISO 10012Accuracy Certificate Traceable to NIST1390000000000000130000000000000000000000000000
    0.0004"36"24"4"ASME B89.3.7, Fed. Spec. GGG-P-463, ISO 10012Accuracy Certificate Traceable to NIST3700000000000000357000000000000000000000000000
    0.0008"48"36"6"ASME B89.3.7, Fed. Spec. GGG-P-463, ISO 10012Accuracy Certificate Traceable to NIST1,203000000000000000———000000000000000
     

    Granite Surface Plate Stands

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

    Calibration Squares

    Image of Product. Front orientation. Calibration Squares. Tri-Squares.

    Tri-Squares

    Image of Product. Front orientation. Calibration Squares. Squares.

    Squares

    Check the tool path of your CNC machine with the highest degree of precision. These calibration squares can lay flat to check that the X- and Y-axes of your tool path are at 90°. Or sit them up vertically to confirm the Z-axis is perpendicular. Made of Laboratory Grade AA granite, these squares have the tightest flatness tolerance available for granite. They also come with a calibration certificate traceable to NIST that states they've passed a test for accuracy. Moisture, coolant, and chips won't affect the granite, so they remain accurate even when used inside a milling machine. You can also use them to check the squareness and parallelism of finished workpieces.
    They have drilled holes to reduce their weight and make them easy to position.
    Tri-Squares—Tri-square plates have a face and two edges for checking 3-axis machines.
    Squares—Square plates have two additional edges for checking both 3-axis and 5-axis machines.
    Tolerance per 6"
    No. of Finished
    Edges
    No. of Finished
    Faces
    Lg.
    Wd.
    Ht.
    Flatness
    Squareness
    Parallel
    Color
    Material
    Surface Plate
    Grade
    Certificate Type
    Each
    Tri-Squares
    2112"9"3"0.00005"0.00005"BlackGraniteLaboratory Grade AACalibration Certificate Traceable to NIST0000000000000000
     
    Squares
    4112"12"3"0.00005"0.00005"0.00005"BlackGraniteLaboratory Grade AACalibration Certificate Traceable to NIST000000000000000
     

    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. 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, Oil000000000000
    Jug1 gal.Water BasedModerateStoneDirt, Grease, Oil000000000000
     

    Two-Axis Precision Levels

    Image of Product. Front orientation. Levels. Two-Axis Precision Levels, Straight.

    Straight

    Level horizontal surfaces in two directions at the same time with the highest degree of accuracy. The highly sensitive glass vials on these levels sit perpendicular to one another – place them on the corner of platforms and surface plates to check if they’re tilting sideways, forwards, or backwards.
    Granite Base—Granite chips off instead of denting or deforming when dropped. It also won’t corrode in wet environments like cast iron or steel, so the base always stays accurate.
    No. of
    Vials
    Housing
    Levels
    Lg.
    Wd.
    Ht.
    Sensitivity
    Horizontal
    Cross
    Check
    Vial
    Material
    Material
    Color
    Base
    Material
    Each
    Straight
    4 15/16"1 9/16"2 3/8"0.0002"/1 ft., 0 min/0.1"11GlassPlasticBlackGranite00000000000000
    4 15/16"1 9/16"2 3/8"0.0006"/1 ft., 0 min/0.1"11GlassPlasticBlackGranite0000000000000
    4 15/16"1 9/16"2 3/8"0.001"/1 ft., 0 min/0.1"11GlassPlasticBlackGranite0000000000000
    7 7/8"1 9/16"2 3/8"0.0002"/1 ft., 0 min/0.1"11GlassPlasticBlackGranite0000000000000
    7 7/8"1 9/16"2 3/8"0.0006"/1 ft., 0 min/0.1"11GlassPlasticBlackGranite0000000000000
    7 7/8"1 9/16"2 3/8"0.001"/1 ft., 0 min/0.1"11GlassPlasticBlackGranite0000000000000
     

    Digital Precision Levels

    Image of Product. Front orientation. Levels. Digital Precision Levels.
    You won’t need to choose between precision or convenience with these levels. Their highly sensitive sensor accurately determines level, even when placed on vibrating machinery and equipment. Clearly read the high-contrast display in any lighting conditions – no need to squint to read vials. They stabilize in five seconds after you position them, so you can quickly check the alignment of one part and move on to the next item. You can also view the angle and slope of a surface without a separate tool. When you need to use these levels under machines or in tight spaces between parts, connect them to your smart device via Bluetooth. The free app lets multiple users view readings remotely.
    In addition, the V-shaped indentation on the base means you can rest them on flat and curved surfaces alike. These levels also have a false zero setting lets you set any position as a reference point when you need to replicate angles on multiple surfaces.
    Granite Base—Granite chips off instead of denting or deforming when dropped. It also won’t corrode in wet environments like cast iron or steel, so the base always stays accurate.
    Housing
    Batteries
    Lg.
    Wd.
    Ht.
    Sensitivity
    Material
    Color
    Base
    Material
    Container
    Type
    Included
    No.
    Req.
    Data Connection
    Each
    4 15/16"1 9/16"2 1/4"0.017"/1 ft., 4 min/0.1"PlasticBlackGraniteCarrying CaseYes1Bluetooth, USB-C00000000000000
    7 7/8"1 9/16"2 1/4"0.017"/1 ft., 4 min/0.1"PlasticBlackGraniteCarrying CaseYes1Bluetooth, USB-C0000000000000
     
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