Nice description Rande. Interesting history on the thread and bolt
standards based on the Allied cooperation during the WWII. Then Someone had
to throw METRIC into the mess..... The Funny part is, how long it actually
has taken for the British industries to abandon, the British thread designs.
I used to work in a Triumph, Norton, Yamaha, and Bultaco motorcycle shop
where we had to have everything. That meant tools for whitworth and British
standard (because the Brit bikes still used some of it, SAE for the rest of
the Brit parts, and Metric for the Spanish and Japanese bikes. The hardest
part was finding taps and dies for the Whitworth and Brit Standard stuff.
And that was back in 1975!!! God I feel old....I was 15 and that was my
first real job. A mechanic. Six weeks later I was the service manager.
The two other mechanics were fired for stealing money and parts, and the
Previous service manager was arrested for resisting arrest when they came to
arrest him for getting drunk and Riding his Yamaha 650 through his garage
door at 40mph...it was closed at the time! over one weekend, I was the only
one left. So the owner made me the manager of the Service department. Grew
up in a hurry there dealing with IRATE customers who found out that there
missing parts had been stolen by the previous mechanic!
Life seems....somewhat tamer now.
Rich
> ----------
> From: Rande Bellman[SMTP:rande@thecia.net]
> Reply To: Rande Bellman
> Sent: Sunday, February 15, 1998 5:43 AM
> To: Tiger Network
> Subject: No, not more about threads, please...
>
> >From the January 1965 version of the Rootes Parts List, the crossmember
> to
> frame bolts are 1/2" -UNF by 3 1/4" and all four are the same.
>
> Also from the Parts List... "it became apparent during the war that there
> was a
> need for a common standard of screw threads in the United Kingdom, Canada,
> and
> the United States. The decision to adopt unified threads follows a series
> of
> discussions between the countries concerned, at which agreement was
> reached
> that the Unified Threads are of a mutually acceptable form, pitch, and
> diameter.
> ...There is a little difference between the form of the American National
> Thread
> and the Unified Thread as many of the A.N.F. and A.N.C. pitches have been
> retained
> in the Unified Series. The new threads are, therefore, largely
> interchangeable
> with S.A.E. standards. They are not, however, interchangeable with B.S.F.,
> and
> although B.S.W. have the same number of threads per inch as the Unified
> Course
> Series, interchanging is not recommended due to a difference in the thread
> form.
>
> ...It has been the objective of the industry to ensure that as far as
> possible, all
> nuts, bolts, and castings on which Unified Threads are used, are clearly
> identifiable by markings..."
>
> This is now Rande speaking/writing. The I.D. methods in the parts list are
> a round
> depression in the center of the bolt head, sometimes with a letter(for
> example,
> R) outside the depression, and a series of circles in a row - three (000)
> on two
> opposed flats of a bolt and in line from the head to the end of the bolt.
> Some of
> the nuts with less flat area have only a series of two circles.
>
> U.N.F. and U.N.C are abbreviations for Unified Fine Thread and Unified
> Course
> Thread respectively.
>
> Let me know if any of you want an illustration from the parts catalog for
> the
> thread issue. I can handle those requests via snail mail.
>
> Rande
>
> No, Whitworth hardware is not used.
>
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