Higbee cut

Higbee cut on male thread

A Higbee cut is a specific modification added to the end of a screw thread to create a blunt start, replacing the sharp end typically found on unmodified threads. Named after its inventor Clinton Higbee, this feature reduces the risk of cross-threading when applied to both male and female threads. A blunt-start thread with a Higbee cut is also referred to as a convoluted thread.

History

Clinton Higbee invented and patented the blunt start thread in 1891.

Common uses

Fire service

The Higbee cut is commonly used on the threads of fire hose couplings. The cut's presence and the thread's starting point are often marked on couplings to facilitate proper assembly.

Thread gauges

Gauging used to inspect machine threads often includes a Higbee cut.

References

  1. ↑ ASME B1.7-2006, Screw Threads: Nomenclature, Definitions, and Letter Symbols, The American Society of Mechanical Engineers, 2006-11-17, ISBN 0791830152
  2. ↑ US 447775, Clinton A. Higbee, "Screw bolt and nut", issued 1891-03-10
  3. ↑ "The Higbee Thread". Fire Engineering Magazine. Vol. 1895 16, no. 13. 1895-03-30. Archived from the original on 2021-03-05. Retrieved 2021-03-04.
  4. ↑ Wildland Fire Hose Guide. United States Department of Agriculture: Forest Service. August 1995. p. 5.{{cite book}}: CS1 maint: publisher location (link)
  5. ↑ "Internal Threads". Quality Magazine. 2013-01-13. Archived from the original on 2020-11-30. Retrieved 2021-03-04.