The IET is carrying out some important updates between 17-30 April and all of our websites will be view only. For more information, read this Announcement

This discussion is locked.
You cannot post a reply to this discussion. If you have a question start a new discussion

UNC and UNF fasteners in Britain

Somebody will know the answer to this…


Almost all British machinery manufactured before 1950 used Whitworth, BSF, or BA fasteners. Manufacturers moved towards using metric fasteners in the 1970s and these have been the most commonly available and used family since 1980, although the proposal to use metric fasteners dates back 1965. Whitworth and BSF officially became obsolete in 1948 following an agreement between the UK, US, and Canada to standardise on the American UNC and UNF fasteners for future use. UNC and UNF fasteners were used in British machinery manufactured in the 1950s, 60s, and 70s where they gradually replaced Whitworth and BSF before themselves being replaced by metric fasteners.


1. Were UNC and UNF fasteners used across most industries in the UK or were they largely confined to specific industries such as automotive and machine tools? Were they regularly used in railways or shipbuilding?

2. Were the numbered sizes smaller than ¼ inch commonly used or did industry stick with BA fasteners until they moved to using metric fasteners?

3. Were UNC and UNF fasteners commonly used in construction? What are the most common family of fasteners used to hold together 1960s tower blocks and university buildings?

4. Was it easy to buy UNC and UNF fasteners from hardware and DIY shops in the 1960s and 70s or did they move directly from selling Whitworth and BA fasteners to metric fasteners?
Parents

  • Denis McMahon:

    My first experience of Isometric fasteners in industry was in 1973 when I worked for a while for a subsidiary of Philips.




    There are differences between the head sizes for ISO / ANSI metric fasteners and DIN metric fasteners. There are also JIS metric fasteners with small heads.

    ISO / ANSI metric

    M10 16mm

    M12 18mm

    M14 21mm

    DIN metric

    M10 17mm

    M12 19mm

    M14 22mm


    DIN metric head sizes are more common although I have encountered ISO / ANSI metric on cars built since the late 1990s. The DIN metric sizes includes M7 with an 11mm head, so beloved by the French that no French car is complete without one, but nobody outside of France uses them. A 7/16 inch AF spanner also fits them.

    JIS metric

    M8 12mm

    M10 14mm

    M12 17mm

    M14 19mm

    M16 22mm


    A 14mm head is also found on some M10 fasteners with a fine thread.


     



     

Reply

  • Denis McMahon:

    My first experience of Isometric fasteners in industry was in 1973 when I worked for a while for a subsidiary of Philips.




    There are differences between the head sizes for ISO / ANSI metric fasteners and DIN metric fasteners. There are also JIS metric fasteners with small heads.

    ISO / ANSI metric

    M10 16mm

    M12 18mm

    M14 21mm

    DIN metric

    M10 17mm

    M12 19mm

    M14 22mm


    DIN metric head sizes are more common although I have encountered ISO / ANSI metric on cars built since the late 1990s. The DIN metric sizes includes M7 with an 11mm head, so beloved by the French that no French car is complete without one, but nobody outside of France uses them. A 7/16 inch AF spanner also fits them.

    JIS metric

    M8 12mm

    M10 14mm

    M12 17mm

    M14 19mm

    M16 22mm


    A 14mm head is also found on some M10 fasteners with a fine thread.


     



     

Children
No Data