Kitz Forum
Chat => Tech Chat => Topic started by: sheddyian on May 30, 2014, 10:04:33 PM
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I was reading about screw threads in Wikipedia, on account of a little project I had in mind. Skimming down the page from Metric screw threads, I found the entry for the British Association screw thread.
http://en.wikipedia.org/wiki/Screw#British_Association_screw_thread (http://en.wikipedia.org/wiki/Screw#British_Association_screw_thread)
Where this little gem was to be found :
British Association (BA) screw threads, named after the British Association for Advancement of Science, were devised in 1884 and standardised in 1903. Screws were described as "2BA", "4BA" etc., the odd numbers being rarely used, except in equipment made prior to the 1970s for telephone exchanges in the UK. This equipment made extensive use of odd-numbered BA screws, in order—it may be suspected—to reduce theft.
If that's true, that's delightful :D
Ian
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Well I never knew that!
Perhaps I should keep a watchful eye open for eBay advertisements of boxes of odd-numbered BA nuts and screws!
:lol:
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What a wonderful story!
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As one of God's Poor Orphans - that has the ring of truth. ;D
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If I remember correctly 3BA screws were used on socket /switch box's before they went metric.
As for imperial nuts, bolts, screws I have thousands of them still, from whit-worth, BSF, AF, 2BA,3BA,4BA,6BA,8BA and some smallest ones used in watches etc. and some very large 1" Dia ones. ;)
If I take something to bits I save the nuts and bolts :D
I have also a good range of taps and dies in my workshop .
One of the things we did on my apprenticeship in 1964 was to cut screw threads on a lathe . :D
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I once came across a nut with a 4BA thread and a 5BA head. I was told by a REME Colonel, that this was an Army size to reduce the risk of excessive force causing damage.
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I once came across a nut with a 4BA thread and a 5BA head. I was told by a REME Colonel, that this was an Army size to reduce the risk of excessive force causing damage.
I do think I have some :).
My late father bought army surplus to make things and he always saved the nuts and bolts, that's why I have so many .
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If I take something to bits I save the nuts and bolts :D
But of course - that's what sheds/garages are for. ;)
They're only sorted into 'large', 'medium' and 'small', but I have an extensive (SWMBO says far too many) assortment of nuts, bolts, screws etc recovered from dead appliances.
It's one of those classes of so-called 'junk' that does often 'come in handy one day'. :)