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
  • Former Community Member
    0 Former Community Member
    Andy,

    Can you say what make and model of milling machine this is?

    Someone may have access to a parts catalogue which may indicate the screws used.

    I have found this a lot with older machines when I used to have to repair them, the manuals can be useful to identify threads, even when a hundred miles away from them!!!

    I used to do so much I ended up with a full set of BSW & BSF taps.

    It was rare in my experience to find BA threads on anything other than electrical or automotive equipment.

    Machinery tended to be BSW/F on the mechanical bits.

    Your other option is to drill it out and "Helicoil"* it.

    That way you would know it is 3/16" BSF.

    Unless it is a liquid tight thread this may well be the easiest option, and there are ways around sorting it out if it's a liquid tight thread.


    You can by a kit with 10 1.5xD inserts for around 40 Euro direct from the manufacturer including tax & delivery to the UK.

    *Other manufacturers of wire thread inserts are available.
Reply
  • Former Community Member
    0 Former Community Member
    Andy,

    Can you say what make and model of milling machine this is?

    Someone may have access to a parts catalogue which may indicate the screws used.

    I have found this a lot with older machines when I used to have to repair them, the manuals can be useful to identify threads, even when a hundred miles away from them!!!

    I used to do so much I ended up with a full set of BSW & BSF taps.

    It was rare in my experience to find BA threads on anything other than electrical or automotive equipment.

    Machinery tended to be BSW/F on the mechanical bits.

    Your other option is to drill it out and "Helicoil"* it.

    That way you would know it is 3/16" BSF.

    Unless it is a liquid tight thread this may well be the easiest option, and there are ways around sorting it out if it's a liquid tight thread.


    You can by a kit with 10 1.5xD inserts for around 40 Euro direct from the manufacturer including tax & delivery to the UK.

    *Other manufacturers of wire thread inserts are available.
Children
No Data