Turret Clock Forum by Robin Hutchinson Over 70 delegates attended the BHI's Turret Clock Forum in September, with people travelling from Australia, Argentina and Italy, as well as all parts of the UK. The theme for this year's event, once again ably organised by Chris McKay MBHI, was the Automatic Regulation and Correction of Turret Clocks. Opening the proceedings, Richard Thomas, BHI Chairman, thanked everyone for coming and for making it an international event. Our first speaker was Chris McKay who gave a talk on ‘A Short History of Turret Clock Correction’. The basis for all correction systems is usually to correct the pendulum. The various historic methods used were described ranging from magnetic compensators, adding weights, electrical time correction and synchroniser methods. The conclusion formed was summed up by Chris’s quote that of all the systems used ‘there is nothing new under the sun’. Chris then introduced the following speakers. ‘Pendulum Correction by Intermittant Contact’ by Rob BHI Director and turret clock conservator Geoffrey Armitage Youngs, Tempus Consulting. MBHI with Paul Roberson MBHI, one of the team that looks after A novel approach to pendulum regulation was described by Big Ben. using a small solenoid operated plunger which functions when required acting at finger pressure on the pendulum rod. This requirements, the latest model has a leadscrew in the centre system is capable of both gently adding or removing energy of the bob controlled by a sensor which automatically adjusts from the rod to control regulation, and re-starting a pendulum. the regulation as required. The design features are: an accuracy of ±60s/year, capable of summer/winter time changes, no modification to the clock, ‘A Magnetic Pendulum Regulator’ by Richard White easily fitted, no human intervention and reliability. This system Inspired by an idea from 12 years ago, Richard’s talk in addition to controlling the pendulum, is capable of providing discussed a method of pendulum regulation using an electro- easily accessible historical data. magnet and separate permanent magnet attached to the pendulum rod. He also covered the layman’s theory of how it ‘A Mechanical Pendulum Regulator’ by Martin Butchers works. One of the essential factors needed was the derivation and Eric Beardow, Smith of Derby. of an accurate time signal. Quite a lot of development work Martin described the historic development of the types of was required before commercial manufacture was available, pendulum regulator used, which led to their current model PR the principle of operation being to alter the attraction force (a 300 being introduced. Eric then explained the technical side of gravity modifier) which influences ‘g’ in the pendulum the regulators and the design issues involved, the principle of equation. operation being to alter the centre of oscillation of the pendulum. As a result of later developments and customer ‘Wheel Cutting’ by Peter Watkinson. Peter described the faults and problems associated with turret clock gears and the various methods of repair available to ensure that the principles of conservation and reliability are maintained. Various welding techniques are currently available for repairs to worn surfaces. The methods of wheel and pinion cutting were explained and the difficulty in obtaining correct profile cutters and even how to make cutters. The principles of cutting the various tooth forms for spur, bevel and worm wheels, and lantern pinions, were shown and how to avoid the various difficulties in manufacture. ‘Italian Turret Clocks’ by Dr Marisa Addomine. Chris introduced Marisa describing how her involvement and background with turret clocks developed. In summary, Marisa's interest and knowledge could be described as being the Italian equivalent to that of Chris McKay. Marisa gave a talk describing a virtual grand tour of Italian turret clocks. Astronomical clocks which were regarded as a symbol of importance were described first, followed by other significant clocks. Marisa talked about each clock in great detail. A register of clocks is currently being compiled, but funding and research are hard work as clocks are regarded as the poor Forum delegates inspecting one of the BHI's turret clocks. relation in the category of Italian works of art. 516 November 2012 Horological Journal Chris McKay, Ian Haward and Smith of Derby's Eric Beardow. Tempus Consulting's Rob Youngs explains the pendulum correction device. ‘Servicing Waiting Train Clocks’, Keith Scobie-Youngs. Keith’s talk covered repairs to the Royal Liver Building Waiting 1974 and was not properly repaired. St Mary’s Church is Train Clock. One of the problems facing repairers with clocks currently undergoing a major restoration project, part of which of this type is getting original information to carry out is restoration of the clock to its 19th century condition with the sympathetic repairs and not let mechanisms such as these be re-instatement of hand winding. Completion is due in 2013. replaced by electric motors. If in doubt, Keith emphasised contacting the Electrical Horological Group of the AHS for ‘Winding Turret Clocks in York’ – a new solution by advice. With access to original drawings the principles of Edward Bacon and Andrew Carter. operation can be examined and faults determined. Faults were The contract for looking after and winding turret clocks in York found in various contacts and in the magnetisation of the iron was originally maintained by Geoffrey Newey. Upon his core on the release/latching mechanism. To keep the clock retirement, the issue of looking after these clocks was taken functioning during repair a temporary synchronous motor drive over in 2011 by a group of enthusiasts called the York Clock unit was fitted. Group. Their aims are fourfold: To maintain the tradition of having the public clocks in York ‘Back to Winding by Hand, St Mary’s Church, Oxford’ by displaying correct time. Rupert Griffin. To bring back to life existing idle clocks. Rupert described previous clocks associated with this church. To preserve the city’s timepieces and maintain the mechanical The first clock mentioned in records was in 1469, replaced in and historical integrity. 1524, then 1640. The current clock by Thomas Paris is dated To continue this tradition into the future. 1740. Successive modifications were carried out on this clock, This idea could be a model for other cities/towns/villages to culminating in auto winding being fitted in 1961; this failed in set up systems to maintain their public clocks. Diocesan Clock Advisors Forum by Derek Frampton. Derek presented an overview of the Diocesan Clock Advisors duties and functions. Currently there are 29 Diocesan Clock Advisors covering the 43 Dioceses in the Church of England. In 2010, an email forum was set up between advisors enabling common guidelines and concerns to be sorted out. During alterations to churches, co-operation amongst all advisors is essential to achieve the desired results, the turret clock being one of the treasures of the church and one of the most neglected items. Discussions on clocks continued at every break in proceedings, making this a most enjoyable day. Robin Hutchinson Richard White shows a small movement by Dent fitted with a magnetic corrector. Horological Journal November 2012 517.