The Whitechapel Bell Foundry Reveals Its Secrets

In an unprecedented move, the Whitechapel Bell Foundry is opening its doors to members of the public throughout the London 2012 Olympic Games.

The Whitechapel Bell Foundry is Britain’s oldest manufacturer of bells – it was established as early as 1420 and has occupied its current premises on the corner of Whitechapel Road and Plumbers Row since 1670. The foundry is probably best known for its association with Big Ben, the bell in the Palace Of Westminster’s Queen Elizabeth Tower. Big Ben was forged here in 1858, and to this day is the largest bell to be manufactured on the premises.

The most recent bell to be commissioned by the foundry is even larger however – the Olympic Bell, which is the largest bell in Europe at over 11 feet wide and weighing 23 tons. It is also the bell with the lowest tone in the world – it’s main note (or in campanology terms its ‘hum tone’), is a B on the chromatic scale. The foundry’s current furnaces are not able to produce enough molten metal to make a bell of this size so it was actually manufactured at a factory in the Netherlands which normally produces ship’s propellers.

Olympics watchers might be interested to note that while Bradley Wiggins pulled a rope beneath the Olympic Bell at the beginning of the London 2012 opening ceremony this was a purely symbolic gesture – someone behind the scenes pushed a button to activate it. He may be a superhuman athlete but even Bradley Wiggins isn’t capable of setting the Olympic Bell’s monumental half-ton clapper in motion by hand!

The ‘profiles’ used to shape bells – from left to right: Big Ben, the Bow Bells, the Olympic Bell.

Current tours of the Whitechapel Bell Foundry are rather special, because all the staff are dedicating their time to visitors as they take a break from working during the Olympics. Areas of the foundry which are normally off limits are open to the public, and there are opportunities to talk to staff involved in every stage of the manufacturing process. The tour starts with the women in the office, who show visitors pictures of the founders and materials associated with them, as well as a rather special cabinet which contains documentation and drawings relating to Big Ben, including the original invoice for £572.

Then it’s time to visit the foundry itself, starting with a video that explains how bells are made (they’re manufactured from bronze, with this particular combination of copper and tin commonly being referred to as ‘bell metal’). You then get to see the bricks and loam that make up the moulds which are used to define the outer and inner surfaces of the bell, some finished moulds and the furnaces that smelt the metal.

In the next area of the foundry you’ll discover some of the techniques, both ancient and modern, which are used to make the clappers that strike the bells. Although wrought iron is favoured for clappers because of its elastic qualities this substance is now in very short supply – commercial smelting of wrought iron ended decades ago, except at the Ironbridge Gorge Museum where it is made in very small quantities for demonstration purposes. Needless to say that the Whitechapel Bell Foundry receives most of the museum’s output, and melts down old clappers when it can. Brand new clappers are now made from a specialised type of cast iron which does not have the brittle qualities associated with the metal, and steel is also used infrequently.

The internal surface of a church bell being milled during the tuning process

On your visit you will also discover that the Whitechapel Bell Foundry does not confine its activities to the manufacture of church bells. One of their master craftsmen is on hand to show you the beautifully polished and decorated handbells that he produces (one recent set of bells, emblazoned with the royal coat of arms, was presented as a gift to the Canadian Government by the Queen) and they also make rather more mundane items such as door chimes, small bells for carriage clocks and even the minute ringers that go into traditional fob watches.

The last area inside the forge that you will see is, I think, the most fascinating. Here you will meet their musical maestro, who has the most complex task in the foundry – that of ‘tuning’ the bells. Church bells are over-sized when they are manufactured so that their internal surfaces can be milled down in smaller and smaller increments until they sound the perfect tone and harmonics when they are struck. While the initial tuning process might involve the removal of hundreds of pounds of material, final adjustments often involve the milling of grooves millimetres wide and a millimetre or two deep into bells that might be six feet across and measure in the tens of tons. It gets even more complicated when the foundry is manufacturing a set of bells, because as well as being in tune internally each bell has to be in tune with its neighbours. To aid him in his task, as well as his well-trained ears the foundry’s master tuner uses spectrum analysers and fiendishly complicated mathematical tables to determine what adjustments are required to make a perfectly tuned set of bells.

A reference bell, demonstrating the milling required to achieve a particular sound profile

The final area that visitors will see is the yard – here you will witness a church bell being rung (even a modestly sized bell is deafeningly loud from a few feet away so keep your fingers at the ready – or better still bring some earplugs!) and you’ll also be able to enjoy a tune being played on the Whitechapel Bell Foundry’s carillon. The carillon is the heaviest musical instrument in the world – the foundry’s example is a relatively small one, consisting of twelve bells arranged in semitones that allow it to reproduce almost any piece of music. It is controlled from a keyboard inside one of the offices and can either be played directly or through one of the push-button presets that have been programmed to play several familiar tunes. Carillons are popular in Europe and often have upwards of 40 bells – the largest, however, is in South Korea and has 78 in total.

The Whitechapel Bell Foundry’s twelve bell ‘carillon’

The Whitechapel Bell Foundry will be open every day up to and including 12 August, and you can visit between the hours of 10am and 5pm. Visits cost £10 per person for adults and last an hour or so, depending on how many questions you have for the staff!