RADIAL BELLFRAMES It has long been understood that rigidity of both bellframes and towers are essential if bells hung for change ringing are to handle in a proper and predictable manner. This requirement for rigidity becomes increasingly important as the size of the ring increases; largely due to the fact that the power to weight ratio of bellringer to bell diminishes with increased bell size. To minimise the effect of moving towers Whitechapel has always attempted to arrange bells in such a way that the distribution of loads swinging east-west and north-south reflect the relative strengths of a tower in those two directions. Even when bells are hung in the most advantageous configuration Whitechapel observed that those bells hung closest to the centre of the tower were less affected by tower movement than those hung in the corners. This observation led to the conclusion that in addition to any movement north-south and east-west there was also a twisting motion which exacerbated matters beyond those that could be predicted. In the mid-1930s, Whitechapel was requested to submit proposals for the new Liverpool Anglican Cathedral and to prepare schemes for what was to become the heaviest change ringing peal of bells in the world hung in the highest belfry in the world. Whitechapel was aware that even under the most advantageous conditions handling a bell weighing in excess of 4 tons and where the combined weight of all the moving parts approximated to 5 tons was to be a challenging task for even the most experienced of bellringers. If either the bellframe or tower were to move by any measurable amount the tenor would be rendered almost uncontrollable. Eventually, and after lengthy discussions with architects and engineers, Whitechapel proposed an arrangement wherein all bells swung through the centre axis of the tower, thereby siting each bell in the most desirable position. At the same time bells were to oriented so that the tenor would swing diagonally in line with the corner of the tower. From this simple but unique arrangement the radial bellframe was born.
At the time, Whitechapel imagined this to be a one-off design solution to suit
a unique project. Subsequently however, Whitechapel has been involved in four
other radial bellframe projects and summaries of all five projects are given
below.
All materials employed in the construction of the tower are relatively hard and comprise mainly steel and reinforced concrete. As hard materials usually encourage "clapper knock", Whitechapel proposed mechanically insulating the bellframe from the remainder of the building so that the thud of clapper against bell could not easily be transmitted down through the tower structure. The bellframe therefore rests upon an insulation diaphragm which separates the bellframe from the supporting structure. The bellframe and bells were manufactured in the late 1930s however the Second World War disrupted construction. It was not until 1951 that installation was complete. Washington National Cathedral, USA. (10 bells tenor 32-0-4)
The order was finally placed in 1962 for what was to become Whitechapel's second
radial bellframe and their first to be constructed in steel. As with the
Liverpool bellframe, the Washington bellframe is mechanically insulated from
the rest of the building.
The Expo Belfry, as it become known, made brief appearances not only at Ardingly but also at a number of other locations up and down the country including appearances at Wembley Stadium, Horseguards Parade and television studios at Teddington. Its last appearance was on the dockside at New York before finding its final home in Chicago. Unlike the first two radial bellframes, the Expo bells are equally spaced around a regular octagon whilst at the same time the centre of the bells, rather than the ropes, form a perfect circle. Miami, USA - Trinity Episcopal Cathedral. (8 bells tenor 17-3-20)
Although the tenor was to weigh just 18 cwt, Whitechapel had concerns about the rigidity of such a tall and slender structure. Whitechapel therefore again proposed a radial bellframe even though the additional space required by the bellframe placed it beyond the agreed footprint of the tower. Ingeniously, the architect devised a bulge in the tower at belfry level to accommodate the relatively large size of the bellframe. In all general aspects, the bellframe is similar to that at Washington Cathedral except that it is smaller and for eight bells. As with the Washington bellframe, the Miami bellframe and concrete support are mechanically insulated from the rest of the tower structure to minimise clapper knock. Basildon, Essex - St Martin of Tours. (8 bells tenor 11-2-24)
As with the Liverpool, Washington and Miami frames, the Basildon frame, which is also supported from a reinforced concrete ring, is mechanically insulated from the remainder of the building.
ResuméWhilst each of the five projects is unique, the radial arrangement has in each case provided an elegant design solution which not only minimises the effect of the horizontal forces generated by Change Ringing bells but also creates a perfect rope circle without the need to draw any of the ropes from plumb.Whitechapel has of course proposed radial bellframes for other Change ringing projects. In most cases these proposals have not been taken up partly for reasons of cost and partly due to the general lack of recognition of the benefits of radial bellframes. What started as a Whitechapel design solution for the world's largest ring of bells has remained a uniquely Whitechapel design feature. The Company has little doubt however that the idea will eventually be copied by others as the several benefits become more widely appreciated. (That last paragraph proved prescient. This article originally appeared in 'The Ringing World' early in 2004 and since then someone has indeed copied the idea.)
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The bellframe is unique not only for being the first radial bellframe but also
the only bellframe constructed entirely in reinforced concrete. In order to
improve tower rigidity, the forces generated by the bells are brought down into
the tower structure via massive steel trusses which spring from the ringing
chamber floor and rise through the intermediate sound deadening chamber to give
support to the belfry floor and bellframe.
It was to be another 20 years before Whitechapel was to be commissioned to
construct a second radial bellframe. In a way, the Washington project was
similar to Liverpool in that the belfry was to be positioned high above the
ground which increased the risk of excessive tower movement. Douglas Hughes
from Whitechapel spent a week in Washington with architects and engineers
devising and detailing a range of bellframes for rings of ten bells with
tenors between 1˝ and 2 tons. Conventional and radial designs were considered
in both timber and steel before a radial arrangement in steel was finally accepted.
Just 3 years after completing the installation at Washington Cathedral, Whitechapel
was approached by representatives from the Sussex County Association of Change ringers
with a view to creating on a joint display of bell founding and bell ringing at 'Expo
Sussex 68' which was to be held at the 150 acre Ardingly showground. It just so
happened that Whitechapel had been working on designs for a lightweight steel tower
to house a ring of eight bells with a tenor of 4 cwt from 1965 when the company took
exhibition space at the Churches and Schools Equipment Exhibition at Earls Court. At
that time the proposal was for a conventional bellframe housed within a conventional
style of tower constructed entirely of steel. Engineers had managed to design a tower
wherein the steel skeleton of the tower weighed just five times the total deadweight
of the bells. In fact, the tower was never constructed however the bells were cast
and displayed at the exhibition. Although it was natural that this tower design
should be considered for Expo Sussex 68 Whitechapel's consulting engineers pointed
out that if a tower could be made so that the bells could be swung radially the
weight of tower steelwork could be reduced by approximately 50%. They further
pointed out that the radial arrangement would not only allow the bellframe to be
an integral part of the tower structure but that by careful design the tower could
be easily dismantled and transported from one location to another. The photo opposite
shows a model of this tower/bellframe.
When an anonymous donor came forward to offer the Cathedral a change ringing peal
together with a completely new tower to house the bells the Dean was anxious that
the sizes of both the bells and tower should match the size and status of the
Cathedral. For reasons of economy, the architect proposed a cast in situ
reinforced concrete tower with hoistable form work and walls just 9 inches thick.
It was in March 1957 that Gillett & Johnston ceased trading as bellfounders and
vacated their foundry site in West Croydon. Both John Taylor and Company and the
Whitechapel Bellfoundry purchased some of the redundant plant, machinery and stock.
Amongst the items brought back to Whitechapel was a ring of six from a redundant
church in Colchester which Gillett & Johnston had been storing since the 1930s.
Whitechapel continued to store these six bells until, in the late 1970s, ownership
of the ring passed to the Church of St Martin of Tours, Basildon. The then Rector,
Canon Lionel Webber, worked hard over many years to create a scheme for hanging
these bells and during this time Whitechapel submitted a number of proposals based
upon the Expo Belfry design. In due course, this idea was taken up by the Basildon
Development Corporation's architect, and engineers working for the Parish developed
the idea through to the tall, slender, lightweight glass clad structure that has
now been built. Initially, Whitechapel proposed incorporating the bellframe
requirements into the structure of the tower steelwork thus avoiding the expense
of an independent bellframe. Ultimately, the engineers and architect felt that
for practical as well as aesthetic reasons an independent bellframe structure
should be created. Whilst being broadly similar to the steel bellframes at
Washington and Miami, the structure differs in that the frameside pedestals
are fabricated from 3" diameter tubular steel. As with the Expo Belfry the
bells are placed equally around a regular octagon so that each bell swings
centrally and perpendicular to each face of the tower. Like the Expo Belfry,
engineers calculated that the radial arrangement of the bells allowed for a
relatively lightweight steel structure. Whitechapel was placed under pressure
to accept the maximum tower sway possible consistent with the bells being
comfortable to ring and additionally to minimise their size requirement for
the octagonal plan area of the belfry. In the event, a total deflection of
1.5 mm was agreed, and achieved, whilst the clearance between the flight of
the tenor clapper and the glass wall is just 15mm!