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    32 Products

    Granite Surface Plates

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

    Rectangular Plate

    Image of Product. Front orientation. Surface Plates. Granite 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.
    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.
    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.
    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
    Inspection-Grade A Plate
     
    Black
    0.0001"6"4"2"ASME B89.3.7, Fed. Spec. GGG-P-463, ISO 10012Accuracy Certificate Traceable to NIST72245A1020000000———0———0
    0.0001"12"8"2"ASME B89.3.7, Fed. Spec. GGG-P-463, ISO 10012Accuracy Certificate Traceable to NIST282245A83000000———022455A1010000000
    0.0001"18"12"4"ASME B89.3.7, Fed. Spec. GGG-P-463, ISO 10012Accuracy Certificate Traceable to NIST932245A43000000832245A46000000022455A6400000
    0.00015"24"18"4"ASME B89.3.7, Fed. Spec. GGG-P-463, ISO 10012Accuracy Certificate Traceable to NIST1852245A440000001752245A4700000022455A65000000
    0.0002"36"24"6"ASME B89.3.7, Fed. Spec. GGG-P-463, ISO 10012Accuracy Certificate Traceable to NIST5552245A45000000005302245A480000000022455A66000000
    0.0004"48"36"6"ASME B89.3.7, Fed. Spec. GGG-P-463, ISO 10012Accuracy Certificate Traceable to NIST1,1102245A56000000001,0632245A490000000022455A67000000
     
    Red
    0.0001"12"8"2"ASME B89.3.7, Fed. Spec. GGG-P-463Accuracy Certificate Traceable to NIST202245A104000000———022455A101000000
     
    Surface Plate Stands
    Image of Product. Front orientation. Surface Plate Stands. Mobile.

    Mobile

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

    Stationary

    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.
    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 Steel2196A71100000002196A7120000000
    24"18"3", 4"50036"Painted Steel2196A7210000002196A722000000
    36"24"4", 6"1,20036"Painted Steel2196A731000000002196A73200000000
    48"36"6"2,40036"Painted Steel2196A741000000002196A74200000000
     
    Stationary
    18"12"3", 4"40036"Painted Steel2196A8110000002196A812000000
    24"18"3", 4"50036"Painted Steel2196A8210000002196A822000000
    36"24"4", 6"1,20036"Painted Steel2196A8310000002196A832000000
    48"36"6"2,40036"Painted Steel2196A8410000002196A842000000
     
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