In 1920, after two-decades of succeeding for other precision manufactures, Charles G. Johnson, a Swedish born natural inventor, opened his own screw thread gage company in Hartford, CT. He named his company John-Sons Gage Works – a tribute to his three sons, Clinton V, Paul W and Stanley G, who would help operate, innovate and expand the new enterprise. Charles and his sons fostered a reputation as pioneers in precision thread gage manufacturing inspection. John-Sons Gage Works invented and patented several inspection devices including a ring thread gage, a snap thread gage, a screw thread testing mechanism and a gage for measuring cylindrical and conical screw threads.

The company’s success attracted the attention of the Pratt & Whitney Division of the Niles Bement Pond Company. In 1930, Charles, in concert with his retirement, sold the John-Sons Gage Works company to Pratt & Whitney. For Pratt & Whitney, Clinton, Paul and Stanley continued to oversee screw thread gage development and manufacturing. Through the 1930’s, the brothers invented and patented a gage for tapered screws, a screw thread gage setting device and an internal thread gage.

In 1940, the three brothers left Pratt & Whitney to form the Johnson Gage Company in Bloomfield, CT. The company and its reputation flourished through hard work, persistence, innovative products, and customer satisfaction. In its first thirty years, the Johnson Gage Company invented and attained more than 60 US patents for screw thread gage measuring systems. Johnson Gage Company innovations for screw manufacturing quality control were so ahead of their time that decades passed before the industry adopted comparable certification standards.

Since its foundation, the company has worked with the government to lobby and improve thread and fastener specification standards.

Johnson Gage remains family-owned with Lowell C. Johnson as President since 1979 following the retirement of his uncle and father. The company is the longest continuously running manufacturer in Bloomfield, CT and among the most tenured in the State. Johnson Gage holds nearly 90 US Patents for screw thread measuring devices.

The company remains a leader in screw thread measuring innovations. Latest product introductions include ThreadSpec3 software and “centrax” runout and concentricity inspection systems. Governments, Fortune 500 companies and start-up manufacturers throughout the world use Johnson Gage systems to assess screw thread quality and conformance.

Johnson Gage celebrated its 75th year of operation in 2015 and 2020 will mark the 100th Anniversary of the founding of the John-Sons Gage Works company. The company is a testament to the American Dream realized through hard work, innovation, product excellence, and meeting or exceeding customer expectations.



Charles G. Johnson born in Sweden


Charles G. Johnson immigrates to the United States


Charles G. Johnson forms John-Sons Gage Works in Hartford, CT


Charles G. Johnson invents and patents Ring Thread Gage


Charles G. Johnson invents and patents Snap Thread Gage


The Pratt & Whitney Division of Niles Bement Pond Company acquires John-Sons Gage Works


Clinton V., Stanley G. and Paul W. Johnson (Charles G. Johnson sons’) form Johnson Gage Co.


Johnson Gage opens a new 13,200 sf manufacturing facility on Cottage Grove St in Bloomfield, CT Since inception, Johnson Gage has invented, designed and manufactured all of its gages in-house


For the next 75 years, Johnson Gage is recognized as the industry leader in thread inspection systems and technology


Johnson Gage invents and is granted its 50th gage patent from the US Patent Office


Lowell C. Johnson is granted a patent for a diametrical dimensional gage with rotatable camming


Johnson Gage invents and is granted its 75th gage patent from the US Patent Office


Clinton V. Johnson retires as President of Johnson Gage


Lowell C. Johnson becomes President of Johnson Gage


Johnson Gage completes modernization of its Bloomfield, CT manufacturing facility


Johnson Gage participates as an expert witness in the U.S. General Accounting Office’s reported conclusion that Changes to Specifications of Military Fasteners are Justified


Johnson Gage adopts ISO 9001:2000 specification standard


Johnson Gage introduces ThreadSpec2, fully integrated thread data and analysis software


Johnson Gage introduces JCR-1 “Centrax” Runout and Concentricity Inspection System


Johnson Gage celebrates its 75th year in operation


Johnson Gage introduces ThreadSpec3, an enhancement to ThreadSpec2


Johnson Gage is on schedule for ISO 17025 certification