Selecting the Right Gauge Block

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Gauges can be supplied from 0.1mm to 1000mm in different material and grades.

What Are The Other Dimensions of The Gauge Blocks?

Gauges from 0.1mm to 10mm have a cross section of 30mm (0/-0.3mm) x 9.0mm (-0.05/-0.2) and sizes over 10mm have a cross section of 35mm (0/-0.3mm) x 9.0mm (-0.05/-0.2mm)

What Tolerance Are the Gauges Manufactured To?

Opus metric gauge blocks are manufactured to ISO3650 and the imperial gauges to BS4311-1:2007 , the tolerances can be found on our technical services page or by clicking on the relevant standards above

Which Grade Do I Need?

Opus gauges blocks are manufactured to ISO3650 (Metric Gauges) & BS4311 (Imperial Gauges)

Grade 2 (Workshop Grade)

These gauge blocks are intended for general use on a shop floor for setting and checking parts and inspection equipment

Grade 1 (Inspection Grade)

This grade is normally used in inspection departments and areas to verify the accuracy of other gauges as well as setting electronic measuring devices

Grade 0 (Calibration Grade)

These higher accuracy gauge are intended to be used in a temperature controlled laboratories and used for setting precision measuring equipment along with calibrating lower grade gauges

Grade K (Reference Grade)

These gauges are designed to be master gauges in calibration laboratories for measuring gauges by comparison

How Often Should I Get My Gauges Re-Calibrated?

No UKAS laboratory is allowed to state a re-calibration date for their measuring equipment, it should be decided by a company’s own quality manual/procedure and be based upon usage, storage etc. As a guide industry consensus is that they should be calibrated between 1 & 3 year periods.

What Does Wringing a Gauge Mean?

Wringing is the process of sliding two blocks together so that their faces lightly bond. Because of their ultraflat surfaces, when wrung, gauge blocks adhere to each other tightly.

Multiple gauges can be wrung together to check a required size, always use as few gauges as possible to obtain the length. For example to measure 45mm you can wring together just two gauges 20mm and a 25mm.


How Do I Look After Gauge After Use?

Please download our care of gauge block PDF instructions

Download the Data Sheet Download Here

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Contact Details


Phone: +44(0) 1536 204681
Fax: +44(0) 1536 205272

Unit 15 Maylan Road
Earlstrees Industrial Estate
NN17 4DR
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Tuesday: 08:00 - 17:00
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Saturday: Closed
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