The ‘Unbendable’ steel rule brings together two of the most useful workshop tools, the engineers rule and the straightedge, into one precision made device.

Workshop accuracy begins with a benchmark straightedge as a surface reference tool. Useful for checking whether surfaces are flat or straight, these tools are normally 1-1/2″ high. Their width allows them to easily stand on edge unsupported, leaving both hands free for precise measurement or tool adjustment.

A good steel rule is used to measure actual sizes and is surprisingly accurate when used correctly. Steel rules come in many shapes and sizes. Most common are 6” and 12” variants, which come in flexible and rigid forms. Traditionally high quality steel rules had their scales machine divided, with the graduations inked in black for better legibility.

A few words on correct use of steel rules.

It is bad technique to use the end of a steel rule to align with the edge of the work for a measurement – the end of a rule often becomes rounded off from misuse, and a true measurement will not be made. The correct way is to use an inch graduation as a reference point on the rule, place the graduation directly on the edge of the work and read accordingly. It is also best practice to use a steel rule on its edge to avoid discrepancies through ‘flex’ – the physical dimensions of the ‘unbendable’ helps mitigate this potential inaccuracy.

At just over 2 lb and 1″ square, the 12″ unbendable straightedge and rule is a substantial and precise tool, useful for checking both flatness and accurate measuring. Precision made and ground flat over its entire length to within 0.0010″ it will provide years of reliable service.