[Bell Historians] Clapper failure information request
David Bryant
davidbryant at T7LhWwuxIwPxdu2pyCYPjcYQtF60oAkCtBprno3bjvpBb2iQ07z2fLWcMj2sLDCje7BmxDAB0ExgGl37pjj82g.yahoo.invalid
Thu Mar 9 23:47:03 GMT 2006
An interesting subject!
I would agree with comments about breakages being most likely on large
bells. The clappers in bells under a ton are relatively unlikely to break. I
suspect that if a graph showing percentage of broken clappers against bell
weight was produced it would show that the larger the bell the more likely
clappers are to break, although obviously the results would become skewed
for the very high weighs as there are so few bells in this category.
I've been ringing at York Minster for five and a half years or so, in which
time we've had three broken clappers. One was in the 6th (12 cwt), but this
was one of the original 1925 clappers so I think it had lasted pretty well!
One was in the 9th (25 cwt) - an SG clapper. The other was in the tenor (59
cwt). This was a machined EN16 clapper which had been in use for about 25
years. It was made by Whitechapel, and was massive with a heavy
counterweight. It was designed to be strong so as not to break, and as the
bells were at that time regularly rung up and down the counterweight enabled
the bell to be rung up right.
Following the breakage of the tenor clapper (it broke roughly in the middle
of the shaft) we had an SG clapper made, with the same profile minus the
counterweight. It was not successful, and didn't hit the bell hard enough.
We replaced it with another of EN16, again of the same profile and with a
counterweight (this being smaller than that on the old EN16 clapper). This
wasn't bad, but there was room for improvement.
Most recently (last Saturday, in fact) we installed a new EN16 clapper, made
to the same profile as the previous ones and with no counterweight. It also
has a new and lighter crown staple (we used the existing staple for the
earlier clappers). First impressions of the new clapper are that it sounds
good, and the bell handles markedly better - this is an area which nobody
has touched on yet, but it is significant. Heavily counterweighted clappers
definitely make bells more difficult to ring.
The next experiments planned are (a) to produce an EN16 clapper without a
counterweight, and a shaft of wrought iron profile (one of the existing
clappers will be machined to produce this) and (b) to experiment with a
wooden shaft, using the SG clapper which proved unsatisfactory. We are also
having a clapper for the 10th made up with a wooden shaft - this bell is
quieter than 9,11,12, and we have a broken clapper from it. Hopefully a
different clapper will make it louder.
I think that Bob Smith's article rather bypassed the use of steel in clapper
manufacture. EN16 is perfectly acceptable (and in our experience is better
than SG where very big bells are concerned), and provided the clappers are
machined rather than fabricated there is no problem. Yes, they are expensive
(our most recent EN16 clapper and new staple cost in the region of £1600),
but if we want the back bells of our heavier rings to sound good this is
inevitable. Clapper design for large bells seems to have been largely
ignored for several decades, and it is good to see that ringers in several
towers with big rings of bells are taking the initiative and experimenting.
David
p.s. Brett - did you make the clapper for Dublin yourself?
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