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 Drill bits are cutting tools 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 order ...

that can

drill A drill is a tool used for making round holes or driving fasteners. It is fitted with a bit, either a drill or driver chuck. Hand-operated types are dramatically decreasing in popularity and cordless battery-powered ones proliferating due to ...

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 BROACH warhead is a multi-stage warhead developed by Team BROACH; BAE Systems Global Combat Systems Munitions, Thales Missile Electronics and QinetiQ. BROACH stands for ''Bomb Royal Ordnance Augmented CHarge''. Development of BROACH began ...

. The Harry Watts square drill bit is based on a

Reuleaux triangle A Reuleaux triangle is a curved triangle with constant width, the simplest and best known curve of constant width other than the circle. It is formed from the intersection of three circular disks, each having its center on the boundary of the ...

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 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 pentagon is 540°. A pentagon may be simp ...

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