This is a 150 mm engineers square designed for setting out and checking right angles in metalworking, fabrication and general workshop inspection. The primary use is to provide a reliable 90° reference between a blade and a stock for layout work, squaring components against surface plates or v‑blocks and checking the squareness of machined parts.

The square is manufactured from hardened high‑carbon tool steel (typically C55–C60), hardened and tempered to give good edge retention and wear resistance. Blade and stock are precision ground and lapped to provide true faces and a stable 90° angle; a black oxide finish is applied to reduce surface corrosion and to minimise glare during inspection. The product is produced to workshop accuracy consistent with common DIN/ISO/BS practices for engineers’ squares, offering typical tolerance in the order of 0.03 mm per 100 mm for practical layout and inspection tasks. Thread type, head type and drive type are not applicable for this product.

Typical applications include marking out and inspection in toolmaking, mechanical engineering, maintenance and repair workshops, automotive machining, and model engineering. Welders and fabricators use engineers squares to confirm right angles before tack welding, while toolroom technicians use them in conjunction with surface plates and height gauges when setting up jobs on milling machines and drilling jigs.

Key benefits of this 150 mm engineers square are its durable tool‑steel construction, the ground and lapped reference faces which give a stable and repeatable 90° reference, and the black oxide finish which provides a degree of corrosion protection for routine workshop environments. The hardness of the material maintains flatness and reduces wear during regular use, and the size makes it convenient for both bench and machine‑tool tasks while remaining accurate enough for many inspection duties. The format is compatible with standard inspection accessories such as clamps, v‑blocks and surface plates.

Duchy Fasteners stocks this engineers square as a packed 150 mm item, with other square sizes and bulk pack options available on request; please contact us for current size ranges and pack quantities. Tags: DR34065, HAND T DRAPER TOOLS, HAND T WORKSHOP, HAND TOOLS, TOOLS.