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Achieving precise measurements is crucial in many fields, from manufacturing to scientific research. A calibration surface plate provides a stable and accurate reference plane for these tasks. Selecting the right one ensures the integrity of your work and the reliability of your results.
The top surface of this plate is precision ground to achieve a high degree of flatness and the flatness is 0.0029mm. It is a Grade A (Grade 00) plate and meets DIN876. Weighs 51 lbs.
Granite surface plates meet or exceed Federal Specifications GGG-P-463C and it includes a certificate of inspection. (Note that these are not NIST traceable.)
Granite plates are used for measuring the flatness and squareness of other objects, laying out parts, calibrating instruments, setting up tools, checking parallelism and perpendicularity, and measuring heights with the use of a height gage.
They are also used as a work surface for assembling, inspecting, and marking parts. Non-magnetic and non-conductive. Harder than steel and does not nick or burr.
Granite surface plates provide an unmatched level of flatness for accurate measurement, inspection and assembly across various applications. The accuracy is +/-.0001"/0.0029mm.
Advantages of Granite - Incredibly Flat – precision ground for accuracy. Durable and Stable – harder than steel, non-magnetic and resistant to wear.
Versatile - Ideal for Machinists and Engineers – measuring, inspecting and calibrating tools; Quality Control – ensuring accuracy in manufacturing processes; DIY Enthusiasts – woodworking, metalworking, jewelry making, leather crafting and more.
Tool Room Grade A/00 – The highest standard for flatness. Quality Assurance – meets federal specifications GGG-P-463C. Inspected for accuracy using an autocollimator.
The top surface of this plate is precision ground to achieve a high degree of flatness and the accuracy is +/-.0001"; It is a Grade A (Grade 0) plate
Granite surface plates meet or exceed Federal Specifications GGG-P-463C and it includes a certificate of inspection (Note that these are not NIST traceable.)
Granite plates are used for measuring the flatness and squareness of other objects, laying out parts, calibrating instruments, setting up tools, checking parallelism and perpendicularity, and measuring heights with the use of a height gage
They are also used as a work surface for assembling, inspecting, and marking parts; Non-magnetic and non-conductive. Harder than steel and does not nick or burr
The top surface of this plate is precision ground to achieve a high degree of flatness and the accuracy is +/-.0002". Granite surface plates provide an unmatched level of flatness for accurate measurement, inspection, and assembly across various...
Meets Federal Specifications GGG-P-463C. Inspected for accuracy using an autocollimator. Granite has many advantages. Incredibly Flat - Precision ground for accuracy. Durable and Stable - Harder than steel, non-magnetic, and resistant to wear.
Versatile - Ideal for Machinists and Engineers for measuring, inspecting, and calibrating tools. Quality Control - Ensuring accuracy in manufacturing processes. DIY Enthusiast - Woodworking, metalworking, jewelry making, leather crafting, and more.
Tool Room Grade (A/00) has the highest standard for flatness. This is perfect for the most demanding applications where precision is paramount, such as: High-precision inspection: Ensuring the accuracy of critical components and tools.
The top surface of this plate is precision ground to achieve a high degree of flatness and the accuracy is +/-0001". It is a Grade B (Grade 1) plate.
They are also used as a work surface for assembling, inspecting, and marking parts. Non-magnetic and non-conductive.
Granite surface plates meet or exceed Federal Specifications GGG-P-463C and it includes a certificate of inspection. (Note that these are not NIST traceable.)
Granite plates are used for measuring the flatness and squareness of other objects, laying out parts, calibrating instruments, setting up tools, checking parallelism and perpendicularity, and measuring heights with the use of a height gage.
HHIP 6 X 6 X 2" Granite Surface Plate Grade B 0 Ledge The top surface of this plate is precision ground to achieve a high degree of flatness and the accuracy is +/-.0001". Granite surface plates provide an unmatched level of flatness for accurate...
Granite has many advantages. Incredibly Flat - Precision ground for accuracy. Durable and Stable - Harder than steel, non-magnetic, and resistant to wear. Versatile - Ideal for Machinists and Engineers for measuring, inspecting, and calibrating tools...
DIY Enthusiast - Woodworking, metalworking, jewelry making, leather crafting, and more. Shop grade is a practical and economical choice for everyday workshop tasks. This grade is well-suited for: General workshop use - Providing a reliable surface for...
Assembly - Ensuring accurate alignment and fit of components. Production checking - Verifying dimensions and tolerances during manufacturing. Hobbyist projects - Providing a stable and accurate surface for DIY tasks.
The top surface of this plate is precision ground to achieve a high degree of flatness and the accuracy is +/-.0001". Granite surface plates provide an unmatched level of flatness for accurate measurement, inspection, and assembly across various...
Granite has many advantages. Incredibly Flat - Precision ground for accuracy. Durable and Stable - Harder than steel, non-magnetic, and resistant to wear. Versatile - Ideal for Machinists and Engineers for measuring, inspecting, and calibrating tools...
DIY Enthusiast - Woodworking, metalworking, jewelry making, leather crafting, and more. Shop grade is a practical and economical choice for everyday workshop tasks. This grade is well-suited for: General workshop use - Providing a reliable surface for...
Assembly - Ensuring accurate alignment and fit of components. Production checking - Verifying dimensions and tolerances during manufacturing. Hobbyist projects - Providing a stable and accurate surface for DIY tasks.
The top surface of this plate is precision ground to achieve a high degree of flatness and the flatness is 0.0029mm. It is a Grade A (Grade 00) plate and meets DIN876. Weighs 69 lbs.
Granite surface plates meet or exceed Federal Specifications GGG-P-463C and it includes a certificate of inspection. (Note that these are not NIST traceable.)
Granite plates are used for measuring the flatness and squareness of other objects, laying out parts, calibrating instruments, setting up tools, checking parallelism and perpendicularity, and measuring heights with the use of a height gage.
They are also used as a work surface for assembling, inspecting, and marking parts. Non-magnetic and non-conductive. Harder than steel and does not nick or burr.
Last update on 2026-10-16 / Affiliate links / Images from Amazon Product Advertising API
How to Choose the Best Calibration Surface Plates
Understanding Surface Plate Materials
The material of a surface plate significantly impacts its durability, accuracy, and cost. Common options include:
Granite: Known for its hardness, stability, and resistance to wear and corrosion. It's a popular choice for precision applications due to its low thermal expansion.
Cast Iron: Offers good rigidity and stability but can be susceptible to rust and requires more maintenance. It's often a more economical option for general-purpose use.
Ceramic: Lightweight, non-magnetic, and highly resistant to heat and corrosion. Ceramic plates are ideal for specialized environments but can be more brittle.
Key Features to Consider
Beyond material, several features enhance a surface plate's utility:
Accuracy Grade: Surface plates are graded according to national standards (e.g., ASME B89.3.7). Higher grades (like Grade AA) offer greater flatness and are suitable for calibration and inspection, while lower grades (like Grade B) are for general shop use.
Size and Thickness: The plate's dimensions should accommodate the size of the items you intend to measure or calibrate. Ensure it's thick enough to prevent deflection under load.
Leveling Legs/Supports: Adjustable legs or a stable support system are essential for ensuring the plate is perfectly level, which is critical for accurate measurements.
Accessories: Consider if you need additional accessories like leveling instruments, surface plate cleaners, or storage covers.
Calibration and Maintenance
Regular calibration is vital to maintain the accuracy of your surface plate. The frequency depends on usage and the required precision. Proper maintenance, including cleaning and protection from impacts or contamination, will prolong its lifespan and ensure consistent performance.
Choosing the Right Size and Grade
When selecting a surface plate, consider the largest workpiece you will be measuring. A general rule is to have at least 30% of the workpiece surface in contact with the plate. For critical inspection and calibration tasks, opt for a higher accuracy grade. For general layout and assembly, a lower grade may suffice. Always ensure the plate is adequately supported and leveled.
Frequently Asked Questions
What is the primary purpose of a calibration surface plate?
A calibration surface plate provides a highly accurate and flat reference surface. It's used for precision measurements, layout work, inspection, and calibration of other measuring instruments.
How often should a surface plate be calibrated?
The calibration frequency depends on its usage and the required precision. For critical applications, annual calibration is common. For less demanding use, it might be every two years, or after a significant event like a drop or impact.
What does 'accuracy grade' mean for a surface plate?
Accuracy grade refers to the allowable deviation from perfect flatness. Higher grades, like AA, have tighter tolerances and are suitable for precision calibration, while lower grades are for general shop use.
Can I use a cast iron surface plate outdoors?
It is generally not recommended to use cast iron surface plates outdoors. Cast iron is susceptible to rust and corrosion, and environmental factors can affect its stability and accuracy.
What is the best way to clean a granite surface plate?
Clean granite surface plates with a mild, non-abrasive cleaner and a soft cloth. Avoid harsh chemicals or abrasive pads that could scratch the surface. Ensure it's dry before use or storage.
How do I ensure my surface plate is perfectly level?
Use a precision level placed at multiple points across the surface. Adjust the leveling legs or supports until the plate is level in both directions (e.g., front-to-back and side-to-side).
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