[Bell Historians] dual stays

Roderic Bickerton rodbick at GccwDo9CJjkezArTXoQrTtVlvCK1wPf-7_XUaXSMCKlqxhi3J_VesMPUCyG_RZgbxbKox8gf_wLU3Ne-Pw.yahoo.invalid
Wed Jul 8 11:32:55 BST 2009

I have seen Siamese twin stays. As each of the pair are of the thickness of
a single, they must be rather strong 
I would think they were done for 3 possible reasons.
1, Aesthetics, they look very neat and tidy.
2, If they are cut rather than bent, the double section involved would
overcome the inherent weakness from across grain loading.

3, I note one contributor commented they were lashed together at the outer
If they were rigidly fixed together they would form a triangle and be almost
totally rigid. Lashing would allow movement and give double the spring rate
of a single stay, but the same total deflection to yield, so in principle
could take 40 % more whack before braking than a single stay of equivalent
total cross section aria, applying the same peak gudgeon loading.

That sounds good but not cost effective as a single stay suitably tapered
would give a better result.
o/k the twin stays could also be tapered, but the ones I have seen are
simple square section.

In my total ignorance of this subject can I pose the question - are dual
stays merely a way round positioning one single shaped stay ? - there would
appear to be some logic to this as there would be no need to go to all the
bother of having a shaped stay made and the travel of the slider would be
the same on both strokes.
Howard Smith


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