Gauge Block Sets

Gage blocks, also known as parallel blocks or Johnson blocks, are essential tools for dimensional verification and the calibration of measuring instruments. These precision-machined parallelepipeds have two perfectly parallel opposite faces, spaced by a nominal thickness.

Gage blocks are rarely used individually; they are usually purchased in sets of different sizes arranged in an arithmetic progression. This setup allows the combination of multiple blocks to obtain a wide range of intermediate measurements with fewer pieces, making them highly versatile for dimensional checks.

Parallel blocks are used in various applications. They can serve as templates to verify the dimensional accuracy of a part through pass/fail checks. They are also used as direct measuring tools, providing highly accurate measurements. In addition, they are critical as reference tools for calibrating and verifying the accuracy of other measuring instruments, ensuring high metrological standards in quality control processes. When combined with a block compacting device, parallel blocks can also be used to check and calibrate tools like calipers, micrometers, and bore gauges.