[Elecraft] Metric Standards

[David Dunn]

Glad to see you clarified the terminology!     I specificaly said Imperial
and someone started talking about "English"

BA is actually Metric simply because in spite of it's name it was a thread
invented in the 1880's (approx) by Swiss clock makers.
 a easonably fine thread with steep sides in order to give better strength
in thin metal  .  Think about it - it makes sense.

Regreftfully they are very hard to get these days as I have found to my
chagrin in my key building hobby.

British threads per se were BSF,  British Standard fine and Whitworth a
course thread ideal for Cast iron or soft metals.   With minor differences
that has the same thread  pitch as UNC   except for half inch.  But due to a
shaping of the top of the apex they are not always reliably
intercahngeable.   There is more to it but not worth the details on this
forum.

  David VK3DBD/G3SCD.



On Sun, May 9, 2010 at 7:15 PM, Bob <K2TK at att.net> wrote:

> If it was an "English size" small screw would it  not be in the BA
> (British Association) standard thread form?
>
> But BA was metrically devised.
>
> 73,
> Bob
> K2TK
>
>
> >
> >    There is a difference between "English size" and "Metric size"
> >    standards.  In my experience, the K2 main knob uses a 5/32" hex
> >    key (a.k.a Allen wrench) with no problems.  Didn't have to trot
> >    out my Metric tools.
> >
> >
> >
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