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Granite Straight Edges

High precision Metrology Equipment

Precision Granite Straight Edge (1).jpg
Granite Straight Edge (1).jpg
Granite Straight Edges
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Granite Straight Edges - Product Description

High­quality black Granite Straight Edges from OSS Calibration are manufactured with both narrow faces flat and parallel to each other to provide the most robust and stable surfaces available.

As standard, our Granite Straight Edges are:


  • Engineered with weight-­reducing holes on the non­-measuring faces to create lighter pieces without sacrificing durability and compromising on the accuracy;

  • Designed with wide enough measuring faces to provide stability and reliability in the measurements.

Granite Straight Edges - Uses

Granite Straight Edges that are perfect for accurate calibration of flatness/straightness and parallelism find many uses in various industries.

Straight Edges placed directly on a part or product allow the user to inspect flatness by a sight test that assesses the light pattern between the straight edge and product. The absence of light between the Straight Edges placed along the entire length of the surface (whose flatness is to be checked) against a bright background indicates the flatness of the inspected part.


Thanks to the accuracy of their measuring faces, Granite Straight Edges can be used to inspect the flatness of smaller items and gauges directly on top of the straight edge.

When there is a need for multiple machine beds or working surfaces to be installed at matched heights, our Granite Straight Edges come in handy. Each surface can be independently adjusted until the Straight Edge is level by bridging two machine beds and using an accurate level.

Granite Straight Edges ­ Grades

Our Granite Straight Edges come in two grades depending on the required straightness/flatness accuracy.

Granite Straight Edges Grade 00

Grade 00 Straight Edges are preferred by laboratories and inspection departments for precise calibration and flatness assessing procedures.

Granite Straight Edges Grade 0

Grade 0 Straight Edges are typically chosen for general quality control procedures, accurate on­site installation and verification of CNC machines and ensuring level machine bases.

Granite Straight Edges - Certification

All Granite Straight Edges supplied by OSS Calibration are calibrated to order as per our in­house procedure and tolerances. As standard, we calibrate Granite Straight Edges directly on the granite surface table. Don't hesitate to contact us if you are using this on support points or wish this to be calibrated on airy points 2/9ths from each end.

All certificates include straightness/ flatness and parallelism of both measuring faces. For other standards or specific tolerances, please get in touch with us.

Granite Straight Edges ­ Delivery

1000mm and 1200mm Straight Edges are supplied on a single pallet, while larger straight edges are delivered on a double pallet as required.

All Straight Edges are provided with black transportation cases to aid in handling, storage and transportation while protecting the Straight Edge from unintentional damage.

Why Granite Straight Edges from OSS Calibration

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The quality and accuracy of the products produced at OSS Calibration are unmatched. When it comes to our Granite Straight Edges, Granite Parallels, Granite Master Squares, Granite Surface Tables & Plates, Granite Triangular Squares and Surface Table Frames, you can be sure that these goods are made to last.

All the products that we supply are finished, inspected and calibrated in house by our skilled technicians to ensure they are of the highest quality.

Our extensive industry knowledge and experience in metrology products and services, which we gained over 30 years, allows us to proudly specialise in calibrating and supplying high­quality precision­engineered Granite Metrology Equipment.

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Thank you for your enquiry.

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

Metrology Equipment Calibration Laboratory
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