Mainspring winder with reversible ratchet

James Marten, our glorious leader, took to the bench with a mainspring which had been pulled out of its barrel causing a permanent set. “This is not acceptable” he said, peering over the top of his glasses sternly at the audience and then explained that a mainspring winder could prevent this evil and should be considered an essential bit of kit for any clockmaker’s workshop.

He than produced his mainspring winder, similar to the example illustrated above and a fusee barrel with mainspring inside. Once the cap had been popped off and the mainspring fully wound, James took a pair of short-nosed pliers to grip the end of the spring before removing the barrel – the shorter the nose of the pliers the greater the grip. The spring was kept from unfurling by hand and inspected for sharp edges before being released slowly – during the process being careful to position his body so that he was out of harms way. The spring had a slight set to it and James then demonstrated how it was possible to reduce this by careful systematic bending and corrected the shape so that it would develop inside the barrel with out scraping either end.02

We were then shown a new spring, which was released from its binding, wiped and checked. The first and most important thing was to make sure that the hooking was central and of the right shape. The hooking should, ideally have a flat edge to receive the barrel hook so that it can find its centre inside the barrel and most new mainsprings have oval hole, which prevent this and therefore should be carefully filed to shape -ensuring that no sharp edges are left – and bent so that they readily meet the hook. Once the spring was wound up and fitted to the barrel, the arbor was then fitted and gripping the square with a pair of parallel pliers, James checked to see if it engaged properly with the end of the spring – which it did. The spring was oiled lightly to the tops of the turns, using engine oil, definitely not lacquer (you had to be there) and the cap replaced. The square was then help in the vice and the barrel checked for endshake. James wound up the spring, pausing every now and then to check the endshake. When it was fully wound with equal endshake at every stage, it was allowed to unwind and judged ready for purpose.01

Concluding his demonstration, James explained how to measure a mainspring with a view to replacing it. Using a bench micrometer, he checked its thickness and a ruler to check the height, as well as the barrel’s inside diameter.

James managed to make, what can be quite a terrifying job for the inexperienced workman, look safe and easy – the mark of a true professional!

The first demonstration of the evening was given to us in considerable detail by Ron Rose, who firstly described the equipment required for piercing out intricate designs in brass and other materials, and went on to demonstrate the procedure with great effect.08

A thin metal table with a wedge cut out from it is firmly set up on the work bench to support the job, and a deep throated piercing saw with a round back blade is used. The blades Ron uses are German and can be purchased from Cousins. The choice of blade requires two to three teeth per thickness of work to prevent snagging, and the edge of the metal table can be cut against to reduce the speed of cut when making an intricate manoeuvre. The stroke needs to use the full length of the blade, so there will be constant wear over its whole length, but by using only part of the cutting area it increases wear in a small section and when another part of the blade is used it will grab and break, but lubricant should not be used.


Now for the demonstration. A pattern is glued and rolled onto the work using a mild adhesive. Ron advises to cut to the line as this reduces filing time. (Try it!!). The saw remains parallel with the arm and does not follow the line of the pattern, as the cutting action remains on the same spot. It is the work that is fed into the blade and on the line as was demonstrated with a circle partially cut out by Ron, and when examined against the light one could not see the point of owning a file. The circle was perfect and without jagged edges.


These skills are only mastered over long hours and many years of practise. Ron has been using a piercing saw from the age of fifteen, and has been most generous to share with us some of the lessons he has had to learn the hard way.

Ron received loud and very appreciative applause from the members and guests.

Converting a LINDOW wheel cutting engine to fully automatic indexing and feed

Alan’s talk showed us how to convert a ”LINDOW” wheel cutting engine to fully automatic indexing and feed.

pt265The Lindow is a sturdy machine imported from America by Malcolm Wild it uses conventional indexing and manual feed/return of the cutting tool. This method requires concentration and is open to error especially on unusual and high wheel counts.

Using a couple of recycled stepper motors, some inexpensive toothed belts and wheels, stepper motor drivers and some freely available software Alan was able to convert this machine into a fully automatic and highly accurate wheel cutting engine.10

Alan demonstrated cutting a 29 tooth 0.8 module wheel. Using the software supplied free by Rex Svenson Alan entered the number of teeth and the module, the software calculates wheel diameter and depth of cut the accuracy is shown in this example it showed to be 0.000064” this is so insignificant. The system is a bit on the slow side for commercial use, but this is far outweighed by the fact that you can leave the whole thing to finish the job.

Alan makes all his cutters using the method learnt at a BHI seminar given by Jim Armfield and this along with the REX SVENSON software shows how simply and economically wheels can be cut to a high accuracy.

December meeting

December meeting

PG Tips

We are very grateful to Christopher Hurrion for this month’s lecture. First given in 1992 at the Science Museum with collaboration with Charles Allix he presented the fruits of research into the life Paul Garnier since the publication of the Allix and Bonnert book. Time and experience can only enrich our knowledge.

Image courtesy of Antique Clocks, price and identification guide

Those of us who appreciate carriage clocks owe a great debt of gratitude to Paul Garnier, who has been recognized as the founder of the Paris carriage clock industry. Born Jean-Paul Garnier in Épinal, France in November 1801, he was obliged to start working at an early age because his father died when he was only ten.  Paul (his preferred name) moved to Paris at age nineteen to work for the clockmaker Lépine and attended the clockmaking school of Antide Janvier.  About five years later he established his own business in Paris, showing great creativity and cleverness through inventions such as his version of a constant-force frictionless remontoire escapement which he incorporated in a complicated mantel regulator shown in the 1827 Paris Exhibition.  Throughout his life Garnier had wide-ranging interests, but in my lecture I will concentrate on his work as a carriage clock maker and the various clever and creative things he did in that capacity.  He was the key instigator in popularizing carriage clocks, and he did this with efficient production of attractive case designs and movements (including specifically his patented chaff-cutter escapement) while building his reputation using various versions of his signature that often included descriptive and impressive titles to distinguish and add value to his work.


Christopher Hurrion, a solicitor, has been interested in carriage clocks since being given a broken one nearly forty years ago, which he cleaned and set going again, more by luck than through technical knowledge. He has been legal adviser to the Antiquarian Horological Society for many years and was Master Clockmaker and President of the BHI in 2003. He is still on the Court of the Clockmakers’ Company and is currently and has been for the last seven years Chairman of the Trustees of the Clockmakers’ Museum & Educational Trust, an independent charity which is responsible for the Clockmakers’ Museum in Guildhall in the City of London.

November meeeting

Following the AGM there will be a series of short presentations:

– Duncan Greig presents an inappropriate use of lead solder – how not to repair a tourbillon
– A short film describing the manufacture of high quality gut lines at the Bow Brand factory
-Grenville Johns, to discuss fitting and wiring a 3 phase motor to a lathe
-Morris Fagg, describes a four facet drill sharpening jig and the benefits of the extra facets
-James will present an addendum to his excellent mainspring talk


September 2013, Meeting


The overhaul and servicing of complicated travelling and carriage clocks. 


Our speaker this year needs no introduction to members of the South London branch BHI. But for those of you who are new to our membership my personal recollections of his quiet and unassuming achievements are as follows. Ron’s horological career started when a school careers officer placed two options in front of him over 50 years ago.


A complicated carriage clock, shown for illustrative purposes only. Original image and catalogue entry for this clock can be found on the Antiquorum web archive. 

In Ron’s own words “thank heavens I was right-handed and chose horology” and at the tender age of 15 he took an apprenticeship with Thwaites and Reed; “the alternative would have been a typewriter engineer”. My first recollection of Ron was visiting the workshops above Strike One Islington in 1978. Already established as one of the top restoration businesses in London I appreciated the fine work displayed in the workshops. Learning of his recent publication of a book on English Dial Clocks I made it a priority in my Christmas list that year. I next saw Ron with his family exhibiting at the Clocks for Everyman exhibition 1980. Ron had to move his business from Islington and many of us have visited his shop on the junction of the Five Ways at 731 Sidcup Road, where he looked after the trade and public alike. Ron has always taken an active interest in the BHI helping his fellow horologist with work and advice when needed; he has trained three apprentices that I know of. In the 1990s he encouraged members of the South London branch to construct a skeleton clock at Upton Hall. This led on to setting up a workshop in 1998 for those individuals who wished to take part in the millennium project constructing their own skeleton clock. There were both professional and amateur alike working side-by-side revelling in the support that Ron gave them. The late Beresford Hutchinson was one of those members. For this Ron was awarded the BHI Barrett Silver Medal in recognition of his services to encourage the furtherance of horology. Ron’s own clock, his second, a month duration striking skeleton clock, is testament to his high standard. Ron has taken part in the Art in Action demonstrations, is a member of the Worshipful Company of Clockmakers and was part of the examining board of the BHI. I have nothing but a high regard for his skills and ability to overhaul some of the rarest carriage clocks that collectors and dealers have placed in his hands. Over the years I have observed the high quality and reliability of his work with complicated traveling and carriage clocks.

Ron is the driving force behind the South London branch and without his perseverance the current workshop would not have come to fruition. Ron still continues to impart the knowledge; skills and camaraderie he has done for many years with this lecture which will include minute repeating work, Grand Sonnerie repeating work, lunar work, perpetual calendar work, a short video presentation and the work of James Ferguson Cole.

D. Greig

From the SLBBHI Workshop


We thought it may be interesting to show some of what as been going on in the SLBBHI workshop during the evening classes.

Let me first set the scene. The class is made up of a mixed bag of ‘students’ with a range of abilities including those with many years of prior horological experience, through to myself with almost none. So far, each student brings in their own projects to work on. Each gets individual attention from Ron and, on welcomed occasions, James, with advice on how to proceed, problem solving, associated history, and subtle encouragement for further study. The evenings are frequently punctuated by talks or demonstrations given to the whole class by Ron. Everyone takes an interest in the other students’ projects. In this way the learning opportunities are frequent and cover many aspects. I am looking forward to the next class before I have left the current.

Onward! To describe a project, chosen just because it is mine, and my first ever dabble in the practical aspects of clocks:

The subject is a weight-driven winged lantern clock by Thomas Dyde, Londini, probably dating from around 1660’s. It has been in my family for about 50 years. It has not been cleaned or given much care since it was first restored after being purchased as a box of blackened parts from a shop while on family holiday in Yorkshire. For most of those years it has been running and I have childhood memories: of it’s tick; of watching the pendulum swing in and out of the windows in the wings; and of raising the weight and the pleasing sensation feeling the click while pulling the rope. In recent years it had become tired and would need to take a nap after a few minutes of running. So, it has been temporarily entrusted to me to enliven.

At the start, I had no intention of writing about it so I don’t have any pictures of the initial condition. On first opening the sides it became clear what the probable cause of it’s unreliable performance was: cobwebs and the remains of a diverse range of arthropods. The attention of a 2″ paint brush completed the problem solving but I took the opportunity to dismantle, clean the components with lighter fluid, remove surface rust from the iron components with a fiber-glass pencil, reassemble, and oil. Here are some pictures of the result, with some comments on things I learned, with Ron’s help, along the way.

Lantern Clock

So you can see what I’m talking about, here is the clock, cleaned, and in the sun.







The first point of interest along my journey that I want to share was the minute-hand wheel. The hand sits over the square end. In it’s current state, the hand is held on by a washer and a pin through the steel shaft which the wheel rotated on. However, Ron notes that originally the hand would have been held with a clip that sits in the groove in the square end. The first clue to some changes the clock has seen over the years. The wheel also shows signs that the strike pin has moved and that a tooth has been replaced due to a stress crack that started at the original location of the strike pin. (click pictures for full-size)


Another example of a replacement tooth, and the first I noticed, was not dovetailed as the minute-had repair has been, but instead has a round mortice profile. This is on the wheel that takes the weight (I’m not up to speed on terminology yet, despite being told).


This wheel also shows signs of alterations. The click stop has been upgraded from a latch spring that would have engaged the wheel spokes (and there is considerable wear on these as evidence) and given a ‘stop’ every quarter of a turn of the wheel, to a more fine latch on a new wheel mounted alongside.


More on the subject of stress fractures in cast  brass, here is a repair to a crack…


In detail, a stress-relieving stop hole drilled at the end, and a supporting plate riveted in place. It seems that the crack may have been aggravated by a replacement bush:



Someone in the past, who perhaps wanted to avoid riveting a replacement bush in a material prone to cracks, has opted for a more raw blacksmith technique to close up an oversize hole. (By the way, Thomas Dyde had a blacksmith apprenticeship  and was not known to be a member of the Worshipful Company of Clockmakers so in some way this seems appropriate here but probably not generally recommended for fine clock restoration!) The metal around the pivot hole has been ‘moved’ to close up the hole by using a round punch around one section of the perimeter. The punch has been applied to both sides of the hole.


There are more photos available on Google+

August meeting

MARION SMITH –  Researching 18th and 19th Century Lewes Clockmakers.

Pre-talk blurb:

Marion was born, and still lives in Lewes Sussex. She was first introduced to Lewes clockmakers when she visited the longcase clock exhibition convened by the late Michael Sautter, at the premises of Bill Bruce. The longterm storage of a longcase clock by John Holman of Lewes, belonging to her nephew, served as a perpetual reminder that there was some research to be done!

A Richard Comber clock dial showing his unusually refined style - from

A Richard Comber clock dial showing his refined style – from


Marion is a retired psychologist, with a post graduate qualification in social science research methods. Local history research is somewhat different. But there was enough common ground to give her the impetus to launch into the local archives, assisted by access to the books and extensive knowledge provided by Bill Bruce.

The talk will follow the course of her research into 5 significant Lewes clockmakers; considering starting points, sources, recording information, overcoming confusion and maintaining the accuracy of research findings.

The Tale of an Aluminium Tube Or don’t throw it away you might need it

When I was sixteen my father and I bought a Drummond “B” lathe from the swap shop in Croydon. I am now sixty seven and still using the lathe after it came to me upon my father’s death some years ago. Over the years the lathe has had a bed regrind and various modifications including, electronic three phase speed control, a new lead screw and an extended cross slide.

In amongst all the bits and pieces was an aluminium tube about an inch long with markings around it. (See fig 1) Over the years I have considered throwing it in the scrap box as I could never find what it was for.


Recently I attended a course at the BHI to learn how to make fly cutters for wheel and pinion cutting. At the course we learnt to make a form cutter and then how to use this to make the fly cutter. This involved using the form tool on the secondary slide set at an angle to cut the blank.

The secondary slide for the Drummond is normally in the cupboard as I do not use it very often. As it was stiff in operation I stripped it and cleaned the thread adjusted out the back lash and considered what set up was required for cutting the blank. During the strip down a plate fell off with a notch on it, I examined it and reconsidered the o ring on the winding shaft. (See fig2)


Suddenly the light came on and I realised what the tube was for, found it in the draw, sliding it over the shaft and the o ring. My father had made and fitted an imperial vernier for the lead screw.

Having decided that the pitch of the lead screw was ten to the inch how was I going to measure the feed in millimetres?

I turned up a length of brass to fit the shaft. A tenth of an inch is 2.54mm so using my electronic dividing machine I scribed lines at 7.0866141730 this being 0.05 of a mm. The odd 0.4mm was painted black, so one turn bar the black bit is 2.5mm. (See Fig 3)


Rotate the curser round to lose the black bit and I can use the imperial; lead screw to measure mm.  With this device I can measure the feed down to 0.05 of a millimetre. (See Fig 4)