Watts Brothers Tool Works

{{Short description|American tool manufacturer}}

{{Infobox company

| name = Watts Brothers Tool Works

| hq_location_city = Wilmerding, Pennsylvania

| hq_location_country = United States

}}

Watts Brothers Tool Works is a tool manufacturer located in Wilmerding, Pennsylvania. They are known for manufacturing drill bits that can drill square holes,{{cite web

| url = http://makezine.com/2009/10/06/drilling-square-holes-with-a-watts/

| title = Drilling square holes with a Watts drill

| last = Ragan

| first = Sean Michael

| date = October 6, 2009

| publisher = MAKE Magazine

| access-date = February 23, 2016 }}

{{cite book

|author=Watts Brothers Tool Works

|title=How to drill square hexagon octagon pentagon holes

|publisher=Wilmerding, Pa. : The Company

|location = New York

|year=1950–1951

}}

including blind holes, 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.{{US patent|src=uspto|1241176}} Watts, Harry J.: "Drill or Boring Member", applied for November 1, 1916, granted September 25, 1917Scott Smith:[http://www.mikesenese.com/DOIT/2011/10/drilling-square-holes-with-a-reuleaux-triangle/ "Drilling Square Holes"], in The Mathematics Teacher, October 1993 (Volume 86 Number 7). Similarly, the company also manufactures drill bits for other angular holes such as pentagons and hexagons.