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Granite Master Squares

Precision Black Granite Master Squares with lightening holes.

Granite Master Squares | OSS Calibration Ltd
Granite Master Squares | OSS Calibration Ltd
Granite Master Squares
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Granite Master Squares ­ Product Description

We are pleased to offer precision Black Granite Master Squares, manufactured as standard with 4 face flatness, squareness and parallelism. Our Master Squares have weight reducing holes to aid in handling and maximise usability.

The outer measuring faces are designed and manufactured wide enough to ensure stability and offer an extensive measuring capability.

Bore­-holes that our Granite Master Squares are manufactured with, make them lighter and easier to handle without impacting the measuring capability or stability. For larger Master Squares, these can also be used as lifting points for appropriate equipment, such as slings.

Master Squares with 5 faces calibrated for the relevant features are available upon request.

Please note that when only squareness requires calibration and inspecting, we offer a lighter alternative without compromising on accuracy - Granite Triangular Squares.

Granite Master Squares ­ Uses

As guidance, our Granite Master Squares have the following uses:

Our Master Squares are a perfect addition for laboratories to use as a reference standard for the accurate calibration of gauges and laboratory masters where squareness and/or parallelism are key.

High precision Master Squares serve as ideal equipment for calibrating the X, Y and Z axes of measuring machines such as CMMs and setting an accurate inspection of CNC machine tools while only using one piece of standardised measuring equipment.

Granite Master Squares from OSS Calibration Ltd are corrosion-­free and less affected by temperature and environmental changes. They offer a great alternative to cylindrical squares for industries where accuracy is crucial during inspection and manufacturing.

OSS Granite Master Squares Tolerances

Inspired by national and international standards, we have developed in-­house flatness, parallelism and squareness tolerances to ensure our Granite Master Squares provide the most accurate measurement capability. Our Master Squares are supplied in a choice of 2 Grades depending on the accuracy required.

OSS MS Grade 00 Tolerances

Grade 00 Granite Master Squares­ offer the solution for reliable and accurate calibration of squareness and parallelism in laboratory conditions. Our highly-accurate Master Squares are ideal for machine installation and inspection.

 OSS MS Grade 0 Tolerances

Grade 0 Granite Master Squares­ from OSS Calibration offer the solution for stable and repeatable inspection of parallelism, squareness and straightness of manufactured parts and products. These squares are often used throughout the manufacturing process with a Grade 00 reference standard used for final verification. 

Granite Master Squares ­ Certification

Calibration Certificates and conformance statements to other standards and tolerances are available upon request. Certificates provided by OSS Calibration Ltd include squareness, flatness and parallelism of all 4 outer measuring faces. Please let us know if you require compliance with specific standards or tolerances.

Granite Master Squares ­ Delivery

300mm x 300mm x 50mm Master Squares are delivered via courier. Larger Master Squares are supplied on pallets.
All Master Squares are provided in black transportation cases. These cases protect the square while transporting and storing the product when not in use.

Why Granite Master Squares from OSS Calibration

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When it comes to precision in measurement, nothing beats the high-­end granite measuring equipment offered by On Site Service (Calibration) Ltd. We offer a comprehensive range of market-­leading granite precision metrology equipment you can rely on.

All precision granite measuring equipment supplied by OSS Calibration has been hand finished, inspected and calibrated in the UK by our skilled technicians.

Thanks to our extensive industry knowledge and experience in metrology products and services, we proudly specialise in calibrating and supplying high­-quality, precision-­engineered Granite Master Squares, Granite Parallels, Granite Straight Edges, Granite Surface Tables & Plates, Granite Triangular Squares, Surface Table Frames.

We've been in the industry for nearly 30 years, and we want you to know that we're here for you. Our customers come first, and we always do our best to make sure their needs are met.

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On Site Services (Calibration) Ltd
10 Cavendish Avenue
NG21 9NQ

Metrology Equipment Calibration Laboratory
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