At 15:34 -0500 23/4/09, Porritt, David wrote:
>I generally don't twist bass strings. If I install one and it
>sounds like it needs a twist I'll do it, that of course makes an
>extra step but if I had very many that need twisting, I'd
>contemplate a different string maker. I think well made bass
>strings shouldn't need twisting.
It's not as simple as that.
It is true that with certain special exceptions, which I won't go
into, a well made string will not buzz or sound bad if you don't
twist it, but, as I've explained at least twice before on this list
of very short memories, if you do not twist the string then you are
putting on twisted strings, and twisted in the wrong direction at
that.
There may be one or two over-enthusiastic stringmakers in the world
who pre-twist the steel core on the machine before winding, but it is
a rather pointless exercise in a market that generally speaking has
learned to twist covered strings on installation.
When the steel core is hitched to the pin end of the machine, clamped
in the chuck end and tensioned, it is, of course in equilibrium, not
twisted. The copper is then wound on to the steel, and this copper
is held under tension during its whole journey from the flattening at
one end to the flattening at the other. It is therefore exerting a
twisting force on the core wire.
The wire cannot twist while it is clamped in the chuck, but as soon
as the string is released from the machine, the copper will release
as much of its stress as it can by twisting the core wire. The
degree to which it will twist the core is dependent on the thickness
of the core and the amount of stress in the copper. There are
extreme cases (which I said I wouldn't go into!) where, even though
the stringmaker has applied the proper maximum tension to the copper
during winding, the thinness of the core combined with a heavy cover
exerting a strong twisting force leads to too great a release of
tension in the copper, accompanied by considerable twisting of the
core, and the result is that the string will actually buzz if it is
not twisted on installation. Several Blüthner models have such
strings, but they are rare.
There is a limit to the tension the stringmaker can give to the
copper, because, in the case of thin copper the copper will break and
in the case of thin cores and heavy covers, the eye or the chucked
end will break. The stringmaker learns from experience the maximum
proper pull for each combination.
On the other hand the stringer is not so limited. What is simply not
possible for the stringmaker can be added by the stringer not only to
_restore_ but to _increase_ the tension of the copper winding. What
_must_ be done is to _restore_ the stringmaker's tension by twisting
the string say half a turn to undo the twist it got when it left the
machine, and what is better is to increase the tension by twisting
yet more. No matter what blessed stringmaker made the strings, the
sound will improve by twisting them.
To answer the original question, if the winding goes like this //////
you twist clockwise and if it goes like this \\\\\\ you twist
anti-clockwise.
JD -- Stringmaker
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