[Bell Historians] Tucking up vs hanging out 'old style'
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itsabubble at ...
Sat Nov 5 21:03:39 GMT 2005
Rod Bickerton;
> Time for some maths.
> As a bell is tucked up its speed increases until the point is
reached when the counter balancing effect starts to dominate and it
slows again.
> Obviously the calculations must include stay wheel and stock mass and
> inertia.
As I said there is a BIG misconception among ringers about tucking
bells up. This theory Rod has mentioned works well for pendulums
swinging up to around 6 degrees. However when the amplitude increases
beyond 6 degrees up to a full circle, this theory doesnt hold true. As
I said in my previous posting the, effect of potential energy
transfer to kinetic energy (mgh = 1/2M[Vsquared]) plays a far bigger
part in the speed of the swinging bell.
The mass and inertia of the stay and wheel are relativley
insignificant considering they weigh about 15-20kg, at the same radius
from the gudgeon as the bell, which will typically weigh at least 10
times more. Im not saying that it wont affect the bell, because it
will, but it is relativley insignificant compared to the other masses
involved.
David Bryant;
>I can think of several twelves where the
>trebles are hung well out and are extremely fast.
Doesn't this just back up my theory? Hang big bells out too, and they
will also be easy to turn over fast!
Rod Bickerton;
> Life gets really complicated if an attempt is made to include the
clapper
> which is not moving at the speed of the bell.
Life actually gets easier! Because of hanging the bell out, means you
do not need as long crown staple to get the required throw, so instead
the clapper can be relativley longer and as a result can enable its
small pendulum swing time to be less than 0.9 of that of the bell.
This is far harder to achieve when you have tucked a bell up, meaning
that you are restricted to only using a short shafted clapper with a
relativley long crownstaple to get the desired throw, this gives a
clapper with a faster swing time than 90% of the bells' swing time
without a counterballance, and gives a bell that has a far better
chance of easily going up right with one person!! (I am referring to
bells of around 20cwt+) A good example of this is St Thomas' tenor in
Bristol (29cwt), goes up right easily with one person. Wooden
headstock, big wheel, no counter ballanced clapper, and relativley
hung out.
Ideally clappers have to swing slower than the bell, to have a bell to
go up right!
> Has this ever been analysed? is the information available?
Im sure the bell hangers such as WCBF and Taylors all did the
calculations on this at least 100 years ago.
As a result over the last 100 years, bells have been more and more
tucked up for several reasons, probably as a result of ringers requests.
Typically these would be
a) to fit more bells in towers on one level
b) to reduce the forces exerted on the tower by the bells.
c) to give the elementary ringer a 'easier' bell to ring.
When I say 'easier' I am meaning that the bell will 'go' at only one
'speed' after being tucked up and with a smaller wheel, the ringer has
to exhert a greater force in the rope to influence what the bell does
to gain the same element of control, as the ringer has less mechanical
leverage over it.
I am not suggesting that what the bell hangers do nowadays is wrong,
as they are only responding to the demands of the common ringer who
thinks they know best.
We should bear in mind that hanging bells out particuarly round the
back end (old style) adds another key element of character to the
ring. Something else we should be preserving when old rings are re-hung.
Philip M Pratt.
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