catalog 9203-1 - MacLean Fogg Component Solutions

The ESNA ® Story
The ESNA ® story began in 1927, when a young engineer named Carl Arthur Swanstrom
came to this country from Sweden. He brought with him a license to manufacture and sell
a unique new self-locking fastener. The Inventor called the new fastener an “Elastic
Stop ® nut” because the nut remained “stopped” anywhere along the bolt threads. A nondamaging
insert, fitted into the top of the nut, gripped the bolt threads firmly, holding the
nut in position without seating against the work or using secondary locking devices.
The only problem with the new nut was the inability to mass produce them. The next few
years were spent perfecting a automatic assembly machine to insert the locking device
into the top of the nut. Swanstrom perfected the machine in the early 1930’s and only
four years later the Elastic Stop ® Nut Corporation of America was founded.
A threaded fastener, able to positively resist the loosening effect of vibration, had long
been sought by manufacturers of every type of equipment. The Elastic Stop ® nut proved
to be the answer—totally reliable, able to reduce maintenance costs and prevent equipment
failure.
The outstanding performance of the Elastic Stop ® nut was further substantiated in 1943
when the Air Force tested and issued the first approval letter to use ESNA ® fasteners on
military aircraft, both fuselage and engines. During WWII billions of Elastic Stop ® nuts
were produced for every branch of the armed services. A staggering number of applications
followed on ground support and electronic equipment.
In the years that followed, the ESNA ® line of standard products expanded to over 25,000
parts. New types of self-locking fasteners were introduced to the product line. . . The
Eslok ® , self-locking hex nuts for low cost commercial grade applications, and the Collarlok
® , a hex nut with a 360° bonded nylon collar for high speed automatic assembly techniques.
All metal locknuts were developed for applications with high heat or weight reduction
requirements.
This diversified line of reliable fastener products has provided Elastic Stop ® nut with a
solid foundation for long term stability and future growth.
The ESNA ® product line may be found in farm, automotive, mining, aerospace, marine
and electrical assemblies of all types.
In 1995, Elastic Stop ® nut became a part of MacLean-Fogg ® and MacLean-ESNA was
created. The following pages describe many of the products produced in a 120,000 square
foot facility in Pocahontas, Arkansas. MacLean-Fogg/MacLean-ESNA represent a company
with capabilities unparalleled in the fastener industry.
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