Watts Brothers Tool Works is a tool manufacturer located in

Wilmerding, Pennsylvania Wilmerding is a borough in Allegheny County, Pennsylvania, United States. The population was 1,781 at the 2020 census. It is located southeast of Pittsburgh. At the start of the twentieth century, it had extensive foundries and machine shops o ...

. They are known for manufacturing

drill bits A drill bit is a cutting tool used in a drill to remove material to create holes, almost always of circular cross-section. Drill bits come in many sizes and shapes and can create different kinds of holes in many different materials. In orde ...

that can

drill A drill is a tool used for making round holes or driving fasteners. It is fitted with a drill bit for making holes, or a screwdriver bit for securing fasteners. Historically, they were powered by hand, and later mains power, but cordless b ...

square In geometry, a square is a regular polygon, regular quadrilateral. It has four straight sides of equal length and four equal angles. Squares are special cases of rectangles, which have four equal angles, and of rhombuses, which have four equal si ...

holes, including

blind hole A hole is an opening in or through a particular medium, usually a solid body. Holes occur through natural and artificial processes, and may be useful for various purposes, or may represent a problem needing to be addressed in many fields of en ...

s, which cannot be made with other methods such as

broaching Broach may refer to: * Broaching (metalworking), a machining operation that uses a metalworking tool with a series of chisel points mounted on one piece of steel * Broach (nautical), a sudden loss of control of a vessel caused either by wind actio ...

. The Harry Watts square drill bit is based on a

Reuleaux triangle A Reuleaux triangle is a circular triangle, curved triangle with curve of constant width, constant width, the simplest and best known curve of constant width other than the circle. It is formed from the intersection of three circle, circular dis ...

shape. It is used together with a guide and a particular chuck to make a square hole.Scott Smit
"Drilling Square Holes"
in ''

The Mathematics Teacher Founded in 1920, The National Council of Teachers of Mathematics (NCTM) is a professional organization for schoolteachers of mathematics in the United States. One of its goals is to improve the standards of mathematics in education. NCTM holds an ...

'', October 1993 (Volume 86 Number 7). Similarly, the company also manufactures drill bits for other angular holes such as

pentagons In geometry, a pentagon () is any five-sided polygon or 5-gon. The sum of the internal angles in a simple pentagon is 540°. A pentagon may be simple or self-intersecting. A self-intersecting ''regular pentagon'' (or ''star pentagon'') is cal ...

and

hexagons In geometry, a hexagon (from Greek , , meaning "six", and , , meaning "corner, angle") is a six-sided polygon. The total of the internal angles of any simple (non-self-intersecting) hexagon is 720°. Regular hexagon A regular hexagon is def ...

References

Tool manufacturing companies of the United States {{tool-stub