The accuracy of cuckoo clocks.

I am often contacted by people who are having the problem of a cuckoo clock either gaining or losing time. The subtext of the question is usually “what the f am I doing wrong – surely the bloody thing tells the time as well as entertains”.

Well the answer is yes. In fact, a recently serviced, or even a not so recently serviced cuckoo clock, can be accurate to within the same tolerances as say, a medium priced mechanical clock. A minute or three out per week but easily adjusted for when you wind the clock up daily. One day cuckoo clocks are more accurate than most 30 hour mechanical wall clocks for instance. There are a few reasons for this.

Firstly the time gearing is well seated with thick pinions. They have a longer functional lifespan so the clock therefore remains in the same frictional dynamic for a stretched out period. About 25 years on a 20th century clock with servicing when performance starts to degrade. Generally that’s anything from 3 pet hair exposed years to a clean pollen free and clean room level of environment.

Secondly, the pendulum is made out of wood. Wood doesn’t stretch over time as metal does. It’s treated wood so it stays in shape and simply hardens over decades. Also wood isn’t known for its expansion under heat and the pendulum is so short it would need to expand like a balloon for it to make any real difference. Lastly the centre of gravity is simpler because the wooden pendulum rod, providing its the length the movement was designed for, is light. The bit that carries the momentum and mass is the wooden leaf shaped (normally) pendulum bob.

The last reason cuckoo clocks can be quite accurate is because they are so simple to adjust in terms of running fast or slow (regulating a clock). You just slide the leaf up and down until you work out exactly where the sweet spot is.

This is the point where you can’t quite work out if the clock is running a minute fast or a minute slow over one day. You can put up with a minute a day adjusted for. Fiddling could achieve watch level accuracy. Sometimes.

Regulation on an 8 day clock takes longer. It’s the same method but with the time difference check weekly when you pull the weights up. You could do it daily but let the pendulum settle into it’s normal arc of swing before starting the timer.

Anyway when you pull the weights up most people knock the pendulum, stop the clock and have to reset the time anyway. It’s just what happens. I do it all the time on test jobs which can be annoying. Just take it easy, like I don’t enough, when you pull the chain. Don’t try and do a Tarzan on it like the grandkids / nephews.

Lastly, because this blog is about insight and helping people ill tell you the method you use to quickly and accurately regulate any pendulum based clock. It’s called “the rule of dividing halves”. Google it.

Just remember that to use the rule, you have to know that moving the leaf up the wooden shift speeds up the swing and therefore the speed of the clock. Just remember “up,faster” and because they are superlative in nature you will remember.

Obviously the opposite applies for moving the leaf down. To be fair, if you didn’t already realise that I genuinely congratulate you on finishing this article.

Cuckoo clock repairs. How can this even be interesting to anyone.

Next time I’ll explain how cosmology works in relation to quantum physics and prove, on the basis of probability, the inevitability of what you mortals call God. Nobel prize stuff. Tune in.

All engineers are multi disciplined scientists..

We work by standards and laws that sit universally in the bedrock of engineering. Clocks for me are by far the best obsession for the determined fiddler solving a puzzle where all your variables have to be defined by theory and observational diagnosis. Across multiple scientific disciplines that overlap. Not easy and sometimes, within the process the diagnosis is as simple as “ “that is most definitely an *NFG bin job – replace that”. On most other occasions its somewhat more complicated.

*NFG [acronym in common use by technical engineers for identifying boxes containing stored failed components. If you ever see a boxed item with NFG in biro on it, you can assume the goods are Not F……..ulsomely Good]

You have to visually apply formulas as known constants and understand they describe ratios not theories. You have to have working knowledge of the geometry principles for calculating linear and arc distances including torque metrics and direction. Its important to know chemistry because if you put the wrong reactive chemical on the worn surface you have to be bloody good at recreating a seamless and invisible covering. So Art in its Aritisan format . This might be enamel, brass alloy, oil pants, water based paints, laquers and the compatibility of all these things is often an issue that needs a process to overcome.

You cant lean it from books because there are so many combinations. You actually need a broad education or interest at a detailed level in the physical and theoretical sciences. Not sub quantum physics, it is incidental to clocks but not an essential part of the engineering education process.

Its all newton pi pythagoras and torque on clocks.

That said molecules and chemistry comes into it. You cant silver a dial without knowing about the piezoelectric effect. You cant understand carbon steel metal fatigue in springs and check for it unless you understand its arrangement and composition at an atomic level. Once you know that, its easy to spot the amplified effect of this on the physical condition of the steel.

This degradation at different parts of the spring due to its usage on rewinds. This varies. Some parts of a spring may have been wound more frequently that others. This is likely. Many clock owners wind their clocks erratically. This means the top of the springs gets wound and bent more often that the top of the spring. Its the laws of averages reaching a human habitual nexus. Unavoidable for 99|%.. To really evaluate an original spring in a good old clock you have to use a method that incorporates that tests for variable fade. Half the spring may be fine and acceptable for occasional use.

The molecular degradation also matters because a springs resistance power increases exponentially with deformation so the centre end of a spring is far more likely to be the point of failure but Ive seen them snap halfway through. At any rate a lot off energy gets released in a very particular way which I will come to.

Most springs do not fail because they have been overstretched. They fail because the molecular bonding that allows their elsaticy breaks atomic bond, by atomic bond over time. This breakage is more prevalent around seams of carbon that are mixed into it to provide a sort of spongy elasticity. Seams of weakness are seeded, connect as they randomly expand, form fractures and integrity fails with a bang and a clock bill.

Unfortunately it usually doesnt stop after the bang. Another thing can happen in that bang, which is an age in the time it takes different forces to build up and release together. Read on.

What then happens is in classic Newtonian format. The conservation of energy is applied. So why is this important or relavent?. Well its because Newton tells us most wisely that we have angular conservation of momentum. We also know from Newton that energy is conserved and tranferred by physical or electromagnetic radiation. On this we are talking physical energy. Kinetic (moving energy – the faster something hits you the more it hursts – more energy), and potential energy (the energy you have to use to get an object from still to moving). To work out how much energy is transferred by the spring break you take the amount of torque energy generated at a tangent to the centre i.e. onto a severly geared down second pinion (a small cog with thick teeth equivalent in circular distribution distance to those on the larger cog – huge torque join).

Ill just do the basic maths here of how much power is tranferred in one go. So you take torque normally generated had he spring been unfurled over time. So thats all the energy it would have taken to keep the pendulum swinging for say 2 days. The velocity issue here is to do with the fact that there will be some give in the gear train when the spring snaps to dampen the shock. But this is a questionable damping force because it allows he momentum of he mass of he whole cogg drum to come into play. So now as well as 2 days operational torque being delivered in a fraction of a second, you have a fraction of a second for the mass of the brass spring barrel in which to rotate very very quickl under huge accelleration force. The amount it moves may be small but the punch it packs when it tranfers its force is disproportionate to the assumptions one might make. In short this means his means Newton again. Force = mass x acceleration applied to the barrel mass in addition to the torgque force created in an instant.

Its outrageous proportional acceleration making the momentum impact force of the cogg teeth quite high all things considered despite its modest scale. The result is that the teeth get stripped from the main barrel like corn under a crop circle UFO. The teeth fold down. Attempting reformation is more like miraculous resurrection. You have to find a way to get a new one, either old spares or make one or talk to your god. We have it covered however.

If I’m just speaking gibberish to you I apologise. The result of all this explanation is that you now know that when a spring snaps there is about a 50/50 chance you may need a new barrel. Some are available spares, some are still made, most old ones have to he lathed out and wheel cut which is a fortune.

For me this is just a fact of life but for you, well, if you got this far you must have at least found it interesting. I really enjoy explaining things in an accessible way but I feel I may have pushed the envelope on this one and if I have bored you I apologise.

We are busy doing all this stuff and I just dont get the time to pass on my work examples or self help or comment posts. Im probably going to do more theoretical and background stuff rather than practical stuff from now on, but even in he article above is an awareness issue which in itself is a contribution to the knowledge base generally.

When I look a the considerable things we have achieved I am reminded that my skills are modest in comparison to the makers of some of the clocks I work on. Challenges are contemporary and have different meanings in different times.

Take the statue of Liberty. Made at the same time as many of the clocks we work on and repair. No boast-able moving parts. I would not have liked to be the engineering specifier on that one.

architect talking to structural engineer: “How thick does the copper have to be on the arm plate bearing in mind it might get hit by a tornado. Shutup. We also dont want the arm to fall into the Hudson due to overweight, and we want to save money on copper. Don’t forget to factor in the three laws of thermodynamics and futurise [made up management word] how this will effect the structural tension of a copper balloon welded round an iron hedgehog holding a Cornetto”.

Oh we repair a lot of cuckoo clocks as well. I just like them and do most of them. We have spares and manufacturer accreditation for the UK.

Recent Web Site Outage Fixed

Just a quick note to explain that the website has been down for a few days. After many interesting conversations with my web server provider about the benefits of clockwork computers they finally sorted out my issue after 10 days. Apologies if you had trouble getting on the website but its all sorted now!.

Massive email backlog.

Because I am literally the only free resource of project specific advice online I am unable to use email anymore. As an example 40% of my time is now unpaid advice via email.

I still enjoy helping people with basic questions and quotes but doing this via email is not economically viable.

From hereon I will only be available on the phone (07462 269 529).

This is not a decision I have taken lightly – it’s just common sense. Why are we emailing each other all the time when a phone call is far more pleasant, efficient and gives you the estimate / conversation you would have wanted in the first place.

ill be removing my email address from the website shortly and expect a %20 increase in customer service.

All the very best,

Justin

For the heroes of clockery who are at their wits end.

I get enough email from amatieur clockists asking for advice. Every clock is different and thats the challenge. I can only offer general advice and that annoys me. Its your fight and you have to persist. If you dont you fail (which is allowed) Its about something else. Its a passion and drive to defeat the gods by knowing their game. It comes with time and hard work. It takes dedication.

Email from Phil Harris – Black Country Living Museum

Ok so this is not actually a blog by Phil but he sent me an email asking why I had not published much recently and if I was OK. Firstly, how bloody nice!. You know if we were all the men that Phil is the world would be a much happier place. Luckily we do have people like Phil and you (hey, why would you be reading this otherwise – its not exactly a summer blockbuster). Incidentally, the reason I dont post as much as I used to is that I now have more responsibities as the business grows. I still love blogging and I will try to make more time for it. At the moment, every second I spend on the keyboard as opposed to the tools ends up costing people who rely on my money or time.

Anyway, back to the point of this post,

You know, people think Curators are some sort of security force or official at a Museum. This article will change your mind about that. Bear in mind that Phil looks after a limited classification of items. I dont think hes into everything, for instance weaving technologies / spinning jenny although to be absolutely honest I dont know and he may be the words foremost expert on 19th century weaving machinery – It really would not surprise me.

The reason Im publishing this is as a doff of the old cap to those brilliant individuals who keep our industrial, engineering heritage alive with their own efforts (as a vollunteer as you will find most curators are). This is important because there is no difference between Elon Musk and the early road builders like Macaddam. You have heard of Macaddam and you think probably think its a brand to do with tarmac (which probably is a brand), but Maccadam was not a brand (I dont think – dont sue me!). He invented a process for laying roads using smaller stones than paving stones. This homogenation of the particulates in road surfaces (all the same sized smallish stones) uncovered what is essentailly a fluid dynamics principle that locks particles within a varying tollerance into what is best considered as an alloy matrix. If you put a load of grapefruit sized stones with a load of walnut sized stones and then lay that down as a foundation of a road, it will cause rutting. You can even see this on modern roads where there are two distinct tracks on the road infront that follow the tracking of everyones wheels.

Macaddam must have spent some time working with different stone sized mixtures to work out the best mix to avoid ruttting. You know that because his tennet was, I believe, “if you can fit the stone in your mouth, its too big for the road”.

That implies measurement and testing. It also means this bloke understood fluid dynamics, even if those principles had not been named centuries later. I mean you have to love it. We were still in the stone age until the mid 18th Century….. or were we?. DId the architechts of Stone Henge lay thier surrounding roads and discover the same thing via repeatable experimentation (the scientific method – formalised by Galileo Galilee in 1650 or so). Who knows. There is always more to do in archaeology

Its all facinating and very intyeresting to find out what you could be if you just do something like work out how to make a better road, even if you dont really understand how its better.

This is the sort of information curators have. People who go to Museums and dont ask curators (available) for information are wasting a huge opportunity. Its lilke buying a blook and then ripping out all the pages that dont have a picture on them.

Anyway, here is Phils emial (very lightly edited for publication but all his own words). There are a some gems in this email……..

Hi Justin, I hope you are keeping well.

I haven’t been in touch for a while, basically because I was a bit worried about you as you hadn’t been posting on your brilliant blog since last March. However today I found your most recent blogs plus your latest piece on Vienna Regulators, and it has prompted me to write to you because I have just been given one! A rather nice Concordia twin-weight Vienna Regulator from about 1883 in a large handsome walnut case. It had been dropped and the pendulum rod was broken. I haven’t stripped it down yet, so I found your latest blog post very helpful. Although I’ve restored several “Vienna-style” spring-driven clocks before, I’ve never had a proper weight-driven regulator and your advice is very sound. To me, it looks in engineering terms a bit like an over-sized and fast-running 400-day clock; the pivots are tiny, the weights aren’t heavy at all, and the pendulum is massive. Apparently the Concordia factory was set up in Germany by ex-Gustav Becker employees, and although the movement is unsigned it is almost identical to a GB. I will take a great deal of care whilst restoring it. Picture attached.

While I’m writing, I hope you don’t mind my sharing the two latest clocks I’ve overhauled for the Black Country Living Museum. The first was an old (1860-ish) Anglo-American clock that they found in semi-derelict and filthy condition under a bed in a disused room. To cut a long story short, this clock was so worn-out it should really have been scrapped, and it took me months to get it going. Someone previously had stripped out the entire strike train, which is why you’ll notice there’s only one winding hole… Almost every pivot hole needed bushing; every trundle in every lantern pinion needed replacing; every wheel tooth needed filing back to a sensible profile; the mainspring needed replacing; the click and rivet were replaced; the dial needed replacing and so did the pendulum bob. Having done all that and more, and cleaned up and French polished the case, it looks good in its new home, the public bar of the recently-opened Elephant & Castle pub. Photos attached.

The second one was a 12″ English Dial fusee timepiece with a short pendulum. The pendulum was missing completely, and it took me some time to source a replacement and get it running to time, but again it looks just the job in the pub’s Smoke Room. I’d never tackled a fusee movement before. This one had no maker’s name on it, but it was a good quality movement, the fusee cable was perfect and the mainspring was smooth, so I chickened out of removing the spring as I didn’t trust my spring winder to hold the power. The other repair demands a confession, which I’ll happily admit to you. The escape wheel had one tooth about half the length of the others. The clock runs for a whole week and keeps perfect time throughout, so I’m happy and so are the Museum! Photo attached.

With my very best wishes,
Phil

[Justin – These are NOT easy clocks – specially the Regulator / Tall Clock. Maximum respect. Even the fusee is a right….]

Ive been busy. Apogies to those who follow this blog. Vienna regulators.

Ok so Ive been rather busy for ages and Ive not pubished to this blog for some time. I enjoy writing it and I know it helps people who want to get into clock mechanics. Education within my community has always been a fundemental from the beginning and I have neglected you. I apologise.

So I feel obliged to pubilish something useful to somebody. That somebody is the person who owns what is known as a regulator, Vienna or otherwise.

These clocks are the devil incarnate. They operate on a very low power consumption and will refuse to work if you speak to them innapropriately (we all talk to our clocks….dont we?. Ok forget I said that).

The longcase clock was developed for accuracy. To cut a long story short the pendulum as a regulatory device spawned the long case clock, however, the prinicple of a long pendulum delivering increasing levels of accuracy comesurate with its length, then began to exetend to other types of clock. Furthermore, with the increase in engineering precision it was possible to not only have a long pendulum providing accurate beat consistency, but it did not really matter what type of clock had that long pendulum. It could be a wall clock for instance. Or a tower clock with the vertical space available.

Because clocks were the top tech of their time, at least that available to the public buyer, there was an almost unstopable market force towards convenience, price and refinement. That is where Vienna regulators come from. Those simple design propositions driven by knowledge and experience. With the development of the regulator you no longer had to have the granfather clock which was essentially a large wooden butler standing in your hallway hicupping every second. You could have a wall mounted piece of techno beauty on your study wall, quietly advising you of the EXACT time.

What a lot of Vienna Regulator owners these days dont appreaciate is why these clock were practical, accurate, and advanced. They were the Tesla Phone of their time. Ill qualify that. A Tesla phone works from a sattelite. Not through wires in the ground. This means it is a step change in the engineering of communication. It doesnt suffer from terrestrial problems of physical “connection” or the frailty of borders or law. It sends your words to the sky and returns them to your desired destination without the majority of connection predjudice (wars, power outages, idiots, profit) and is worthy becuase it is indescrimate. It provides the same simple connection architechture that seems to define successful modern communications.

In the same way the regulator took the basic priniciples of the pendulums newtonian regularity in oscillation to the wall, not the floor. You have to remember that at the time these were produced the only reliable accurate time could be obtained by clumsy floor standing devices or a church. Or a very expensive pocket watch.

To take this accuracy out of the chapel or hallway some adjustments to the ratio of things were required. Firstly, you cant hang 25kg of weights onto the wall withou the whole clock ripping itself from its fixings and becoming modern art on the floor. To achieve the same, or better accuracy, from a wall clock would mean a long pendulum interfaced to a movement that required far less power (think KG) to work. So the regulator was born.

These devices are accurate. They are also particularly low power consumption per tick and tock. Compare the shaving foam cannister sized weights on a regulator with the massive 12kg plus weights on a long case clock. There is a massive degree of difference. So to make what is effectively a wall mounted grandfather clock, something had to be changed. This was the refinement of the mechanics to provide a low friction and energy consumption device.

As a clock repairer this presents problems. With a Gradfather clock you have a huge amount of grunt available to drive the gearing. This means that the cogs dont have to mesh exactly, the friction generated within the mechanism is almost incidental and of no great importance because there is so much power. With a regulator this is turned on its head. The machines are designed to almost conserve power. They operate as accurately as a long case clock but at 20% of the power on roughly the same dial size (all things considered).

Fundementally Vienna regulators use loads of refinement and vectors and spectors/indian shamam spirits and angles to achieve the same thing as a long case. The cost is complexity and low wear tollerances.

I probably get one call a week from someone asking me (as a last resort because they have attempted a home fix),”why does it only run for 3 hours, all it did was change the cables”. The answer is that the clock is so accurately balanced between perpetual motion with a tiny power input, and a clock that consumes more potentail and kinetic energy than the drive (weights) provide.

You may well have taken your regulator apart. You found a relatively low quantity of gears and simplistic engineering design overall. You probably didnt notice just how thin or small the connecting components connection points are. You wont have noticed that the pallets are two bits of carbon steel with screw down variable settings so that you can adjust very precisely how much pallet connects with how much escape wheel tooth. You probably thought it was just another variant of standard clock gearing and functional modules (power, gearing, regulation).

It is hard to overstate the importance of these physical ratios in a regulator. It really is beyond mathematics. With a regulator everything is pushed to the edge of its performance within the power available from two relatively small weights that run the clock for EIGHT sodding days.

Repairing these clocks or servicing them is an absolute nightmare. Its near impossible to quote for these jobs because, potentailly, it could involve re-refining all the gear train components as well as setting the pallets to the right level above the escapement to within thousands of an inch. All of which has to be done by test. There are no manuals. There is no other knowledge on the engineering settings of your clock other than that contained in your service partners brain.

So, if you want your 4ft regulator fixed there are a few things worth considering.

Fistly, if youve already tried yourself because your reckon you know what you are doing and you worked in engineering, but are now retired, you probably quadrupled your repair bill. Your service partner will have no indication of “what was” because youve changed settings, and effecively erased the original settings, by buggering around with it. This means the repair will be based on a first pass of replacing wear, and a much longer phase of working out how all the forces in the gearing deliver a result.

Secondly, do not let anyone touch your precious clock who does not have considerable experience in working with these machines. When I started I lost a shed load of money spending rediculous hours working out what worked and where the likely weaknesses in an machine were. What will probably happen if you give one of these clock to anyone that is less than “advanced”, is that you will not seee your clock for at least a year at which point you will eventually have the “errr.. we cant do it” discussion.

I love all clocks but there is special place in my heart for these time keepers. It is a black bit. Yes you read it right, I dont like these machines simply because its just so easy to underplay the potentail costs and problems.

Thats the negative view of a stressed out clock repairer. My view is that they are beautiful fantastic machines that will keep better time than your Rolex. I know that for a fact. BUT you have to respect the design and principles of these incredible machines before owning one or you will not budget for maintenance at the correct level and end up with a clock you can not bear to lose but cannot afford to fix. Like a hanging corpse.

I may need to go back and redo that “making your business attractive to potential clients” course.

1930’s Long case – Deco. Pendulum Adjustment.

This is a quick one to thank my peers in the craft. Its how to adjust the pendum settings on a domed top, arabic with brass bezel, long case clock. If you are reading this you already know what Im talking about. That said this is for my more advanced readers as well so Ill publish with that in mind.

The pendulum leader has a turning wheel on it. This is there to allow for horizontal alignment of the beat/balance settting process. This hower has a larger guage balance setter in the form of a pallet arbour clutch.

If you get a situation where the wheel doesnt achieve the desired horzontal offset you can remove the pendulum and while holding the suspension spring, force the whole leader left of right beyond its point of natural resistance. I had one of these as a job, and I did this without removing the face or taking the whole shelf and movement out. This is why Im pulishing it; it took half the time and money discovering this “blind”, so I know it can be done by others.

Also these clocks are absolute nightmares to repair generally. The chime control system is under-specified, for the size and of forces the the massive wheights they have can take. Basically, in my opinion the things are a large mantle clock movements in a long cases…….

With massive torque and revolutions per operation. The top level flys clutch sytem fails, then top pinions on it spiin too fast and its rattling or so badly bush worn it take the whole gear train torque transfer down by about 50%. If this was a car (an analogy I ofter use), it would be an Alfa Romeo. Absolutely beautiful, exquisite lightly specified components, and a lot of power in comparison to other long case, and generally much older, clocks. Im not sure if the people who get to own these clocks, often inherited, understand that have been handed a financial bomb with a lit fuse.

Still, intersting clocks when they are completely mechanically restored as they normally have epic chimes.

What cuckoo clock is right for you?

People often approach me to buy cuckoo clocks and are quite surprised when I say I dont sell them, only repair them.

Thats not really a choice for me because despite my efforts to slow the earth and create a 30 hour day (where is Superman when you need him) I really dont have time to sell and fix. Selling clocks is….mostly administration. Its boring. I have no idea what the profit margins are and if I were to sell a cuckoo clock Im the sort of person who would start a cuckoo clock building company. I know exactly the sort of clocks I would make and they would be put together in a way that addresses the problems Ive seen with cuckoo clocks over the years. And heres the thing. Ive just realised I probably know more about cuckoo clock repairs than anyone else in the UK. You might think that the people who sold the clocks you can buy would be the same people that you would go to in order to service the clock every few years but people who sell cuckoo clocks generally dont have a clue on how to service them. Its a peculiar sector or the market because most clocks are bought on holiday and cant be taken back to the original source of purchase independent reapairers like myself take on this role.

Loestcher actually rung me and asked me to become their UK service Centre after seeming some of my blog posts about Antique cuckoo clock restorations. The older clocks are more complicated and we do those. Wooden cage movement clocks dating back to the mid Victorian period often make up a lot of what we do in any given month. I think the best one we have done so far is here…

Anyway this article isnt about bragging or emphasising a specialism, its about what I would think about if I was asked to recomment a cuckoo clock bought new from retail / online

Ive seen, I think, evey type of cuckoo clock made since 1850. Through that I have learned the evolution of this strange branch of Horology. Cuckoo clocks were the first clocks made more for looks than time keeping. You dont need a bird popping out every hour or half hour advising you of the time. You have a watch or a phone.

So cuckoo clocks are about fun. Its really is as simple as that. They are delightful for grandchildren to visit . Interestingly the two most connected things between cuckoo clocks (and their repair) is children, due to the fact that they get exited about the cuckoo coming out and will actually wait, on the hour, to see the bird come out and cuckoo. If the cuckoo doesn’t come out exactly on the hour a lot of children get impatient and try and encourage it by pulling the weigths shaped like pine cones (not exactly discouraging).

Because the clocks are mounted quite high on the wall to allow the chain to drop through 24 hours use, the children pull the chains.. This results in the clock either being wound up so that it jams because the chains are pulled to hard (stretches or breaks the chains), or the clock coming off the wall and smashing to bits (and I get sent a puzzle of bits). About 1 in 8 clocks are sent to us after a child has played “Tarzan” on the chains. What amazed me at first was that no child got injured but then it dawned on me that so see the cuckoo, if your only 2 to 4 feet high, means standing back so you can see the cuckoo door. It also means you are not directly in the path of the falling clock. Its got to the point where if a customer tells me the “clock just fell off the wall” I will ask if the grandchildren have visited recently.

Sorry I am going off at a tangent. I will now tell you about cuckoo clock types and why you should buy each dependent on budget and circumstance.

By far, the best cuckoo clock you can buy is a two weight (275g per weight) small cuckoo clock for up to £500. If you buy a 3 weight clock then it means its got a music box. If you put a music box in a craft clock built by a few people in a Bavarian shed then you can be pretty sure they have either guessed at the power requirement to drive two machines (the movement and the music box). You cant do the torque calculations that will lead you to the theoretical power required to keep the clock going and the music box every half hour. The gearing is not precise enough and the mechanics that lift a bar allowing the cuckoo to go off and then start the movement are pointless to calculate. There is too much variance in the hand building process. So what happens is that somebody designs a clock around standard components and their own styling and they build it. On day one it works find but then if they have cut costs by specifying a music box with a platic worm gear (for instance), while it all works on paper, after a few years it doesnt work. Repairing clocks with music boxes is twice the price of repairing one without.

If you want something a bit more exotic then there is a huge choice of various machines and makers. In terms of clock hierarchy there are three main brands. Loetscher, Huber Herr, and Schnieder. There are others of course but in terms of industry prescience I would say these are the top three. These companies produce some truely impressive machines with dancers, wood cutters, water wheels and moving animals. The only problem is that each of these features are driven bu the weights and Ive noticed some clock manufacturers balance the quantity of power to drive them, plus the power to keep the clock going, quite closely. This means that any reduction in efficientcy via fouling or dust build up stops the clock much more easily than the same amount of fouling on a much more cheaper and equally as fun cheaper two weight.

Servicing every seven to ten years on one of these big 3 weights is…heavy. £400 or so and many larger and more complex clocks have components that are out of production in a few years if he model doesnt sell well. This means paying more, much more, for a fix. Also as you can imagine, all this extra functionality comes at the additional cost – wear. Movement manufacturers, as a general rule, do not produce a movement specific to a power rating (the weight of your pine cone weights), so an arbor and plate thickness is designed to hold “an average” weight”.

Anything running more than 1kg weights will simply wear out more quickly. If the manufacturer cant provide spares then you have to effectively “re-purchase” half the mechanics once the clock is worn, generally after far less time than that of a 275g 2 weight cuckoo only based machine.

Up to 420g will give an average lifetime of 20 to 30 years whereas an unserviced big 1500g 3 weight clock is a third of that. My clock is about 140 years old, double fusee driven 8 day machine and I can tell you for a fact that if I did not love it more than anything else I own apart from my vintage watch (oh and my kids), I would not entertain it. Its too expensive to wear down. I dont run it – I just gloat over it.

The size of your clock is all about the size of our clock. Bigger clock, bigger cost. Such is life.

Hand forged / fired Glass Pocket Watch Glass job

The subject line says it all really, in that we had an expensive pocket watch in with broken glass. The glass was particularly thin and nothing “off the shelf” was ever going to fit. So we made our own.

We did this by cutting the glass blank with a ceramic lathe to exact diameter and then, having made a jigg, used a glass furnace to recreate the original convex curve. The end job is indistinguishable from the original although it is stronger, perfectly polished and a peffect fit.

The cost for this, including a very thorough service was under £1000 on a chiming gold pocket watch valued at around £7000. We are brilliant value for money and have equipment which others simply dont have. I genuinely believe that this job would have had to go to Switzerland for serveral times the cost and I doubt the job we made of it was not just incredibly cheap but also the best possible results in terms of quality finish, materials and strength.

I dont usually do bragging articles but the reason I am doing so on this occassion is that if you a have smashed special fit glass we can do it and we are one of very few organisations that do.

Brilliant job of which we are very proud.