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 2,190 at the 2010 census. It is located southeast of Pittsburgh. At the start of the twentieth century, it had extensive foundries and machine shops of ...

. They are known for manufacturing drill bits that can drill

square In Euclidean geometry, a square is a regular quadrilateral, which means that it has four equal sides and four equal angles (90- degree angles, π/2 radian angles, or right angles). It can also be defined as a rectangle with two equal-length a ...

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. The Harry Watts square drill bit is based on a Reuleaux triangle 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 (from the Greek language, Greek πέντε ''pente'' meaning ''five'' and γωνία ''gonia'' meaning ''angle'') is any five-sided polygon or 5-gon. The sum of the internal angles in a simple polygon, simple pentagon is ...

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'' has ...

References

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