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PROPOSAL FOR

London N7: Islington – Caledonian Clock Tower

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PREPARED BY

Martin Butchers

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DATE

6 October 2014

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Smith of Derby Ltd, 112 Alfreton Road, Derby DE21 4AU United Kingdom

Telephone 01332 345569 Email [email protected] www.smithofderby.com

Registered in England and Wales number 1395408. Registered office as above address.

Our Ref: H/4059/MB/JJG Mr Christopher Hariades London Borough of Islington [email protected]

Dear Christopher London N7: Islington, Caledonian Clock Tower Further to my recent site inspection, I have pleasure in providing my report and quotation for your consideration. We trust it meets with your expectations but please do not hesitate to contact me if you require clarification or further assistance. Yours sincerely

Martin Butchers Technical Sales Engineer Tel: 01332 345569 ext 235 Mob: 07808 760409 Email: [email protected]

mailto:[email protected]

mailto:[email protected]

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1. Observations and Recommendations The clock is a John Moore of Clerkenwell posted frame clock, known as a ‘bird cage’. It has three trains; being the going, strike and quarter. The escapement, which is the mechanism that provides the impulse to the pendulum and releases the power of the clock is a pin wheel type with anchor escapement. It was made in 1856 and was restored in 1909 by a well renowned London clockmaker and in more recent years, 1993, it was overhauled by Smith of Derby.

Interestingly, having spoken to my colleagues here in Derby (some of which have many years experience) I understand that this particular clock was the blueprint and submitted originally for the Westminster clock commonly known as Big Ben. There were four contenders for the Big Ben project; John Whitehurst, John Moore of Clerkenwell, Vuliamy and the company that was finally commissioned, Frederick Dent of The Strand in London. The Westminster clock was built in 1854 and this particular clock, which may have been destined for the Westminster tower, was actually installed in 1856 by John Moore of Clerkenwell. Over the years it has been a little overoiled and greased in the wrong places and whilst the going side is working correctly, the strike side was disabled when I visited. The clock would benefit from a complete strip down and thorough overhaul. We would do this on site using two men over a two week period. This would be the most cost effective solution as a full restoration back to original condition, involving removing the entire clock from the tower to our Derby workshops, would be a very costly exercise to carry out on a clock which is actually working. To overhaul the clock we would need to lower the weights to the ground and at that point it would be advisable to overhaul all the pulleys to all the trains and refit new lines. It is also imperative to service and overhaul the drive train. This is the lower crown wheel bevel sets within the clock framework that leads off through the con rods through the friction roller sets, to the upper bevel sets which are located at dial level and resembles a differential. These lead out via the four lead out rods to the motion works. The motion works sit behind the dials and are the separating ratios from 12 : 1. Most importantly, the dial works (being the hour tubes and minute spindles that go through the dials to which the hands attach on the outside) should be overhauled as they become affected by many years of weather and can seize up and an overhaul at a later date would require either roped access or scaffolding, which again would be a very costly exercise. It is therefore

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prudent to carry out this work when scaffolding is already in position. The photograph below is an example of a set of dial works:

I attach some photographs detailing the clock mechanism, including the rusty suspension springs which certainly need to be cleaned and lubricated to prevent further corrosion and subsequent fracture, which would drop the pendulum. The pinwheel escapement is heavily greased and this should be very clean with only a slight smear of Omega oil on the pins and pallets. A photograph is attached showing the wheels and pinions which are also heavily greased. This is catching grit and will cause considerable wear and damage to the teeth and eventually will stop the clock. The weight lines will be changed at the time the pulleys are re-instated and we will also strip and clean the drive train, which is the bevel gear sets which drive the lower ground wheels within the clock, leading up through the tower through the friction roller sets and into the upper bevel sets, ultimately leading out to the motion works. This would all form option 1. Option 2 is the complete overhaul of the pulleys, these would be removed from site and sent back to our Derby workshops along with various other parts for specialist cleaning and polishing. The pulleys would be completely stripped down and bridles and wheels shot blasted and new axles would be made with gun metal bushes to give longevity. They would then re-painted and returned to site, along with the other components. Option 3 is to overhaul the dial and motion works, which form part of the same piece of equipment. There are four sets and these sit behind the dials and also pass through the dials. The motion works behind the dials are the sets of the gears you will see in the photograph I have supplied. The dial works are the support tubes containing the hour shaft and minute spindle which protrudes all the way through and outside which the hands attach to. These would be overhauled when the dials are restored and this can only be done by access from outside. These would be withdrawn and sent to our Derby workshops along with the pulleys.

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Option 4 is to install night silencing equipment, known as Auto Pull Offs. These would be mounted in specially made frameworks which would sit outside of the building underneath the bell canopy and these would have timer controllers that would activate the actuators that would activate the hammers and keep them in that position. The clock would still strike as normal but the hammers would stay in the off position until the following morning, at a time agreed by the customer. A brochure describing this equipment is attached. Option 5 is to restore the strike hammers, as I noticed during my inspection that these have become quite corroded over the years and I propose we bring them back into our Derby workshop with other items to be shot blasted, repainted and to have the spigot bushes to be remade using gun metal. We would paint them with weatherproof anti corrosion paint. All the cables, wires etc would be replaced at the same time as the Auto Pull Offs are installed. Option 6 is to overhaul the clock dials (rather than a full restoration). Full restoration would require the glazing to be removed, which would be a major operation, and having seen the dials from ground level they appear to be in fair condition. However if scaffolding is to be erected it would make good sense to overhaul the outside of the dials at the same time. We would leave the glazing in place and abrade the castings, followed by the application of weatherproof primer, undercoat and top coat. We would re-gild the centre and outer rings using 23½ carat double thickness English gold leaf and the hands would be re-painted, ready for refitting after the dial works are refitted.

2. Summary quotation

Item Price Notes

Option 1 – strip and clean cage clock Option 2 – overhaul six pulleys Option 3 – overhaul dial/motion works Option 4 - supply and install night silencing equipment Option 5 – restore three strike hammers Option 6 – dials overhaul

XXXX XXXX XXXX XXXX XXXX XXXX

Prices are net + VAT. This quotation is given as per the terms of our Conditions of Contract, copy enclosed. All prices quoted are based on the information we have to date and are valid for a period of 90 days from the date of this letter. Please note that in the event of any further unexpected work being identified, this will form a separate quotation and the work will not be undertaken without approval.

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3. Why choose Smith of Derby Ltd Since 1856 Smith of Derby Ltd has served the horological community to our best ability. With over 4,500 sites under our care we maintain our leading position in the industry through our passion for ‘time’ and through the delivery of the highest customer service levels in the industry. Our work is guaranteed and through hundreds of testimonials we enjoy each year, our delighted customers are our most important asset. With over 60 fully qualified staff, we believe we are the world’s largest and most experienced tower clock service and restoration company. With clocks in over 50 countries and technology patents recognised each year, we are the safest hands to give your clock the care it deserves.

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Photographs

Upper Crown Wheels

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Motion Works

Pin Wheel

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Strike Hammer

Suspension Spring

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