As a clock repairer, there are several compelling reasons to keep the original mainsprings if they are still in good condition.
Keeping the original mainsprings ensures that the clock remains as close to its original condition as possible. Collectors and enthusiasts often value clocks with original parts, as they maintain the authenticity and historical significance of the clock.
Older brass mainsprings are not replaceable
Many older mainsprings were made with higher-quality steel and manufacturing techniques and modern replacements may not be of the same quality. Original springs, if well-preserved, may outperform modern equivalents in terms of durability and performance.
Consider the original design of the movement and how it is powered. The original mainspring is designed specifically for the clock’s movement, ensuring the proper balance of power delivery and running time. Replacements, even when sized correctly, may not deliver power consistently due to slight variations in material and design.
Modern mainsprings can sometimes deliver too much power, especially in delicate or vintage movements, leading to accelerated wear or damage to gears and pivots. Original springs are often “seasoned,” meaning they’ve been conditioned by years of use and may be gentler on the movement. Even replacements that have the same dimensions as the original are overpowered. Recommended replacement springs might overload the movement and lead to wear issues sooner rather than later.
Laurie Penman, who authors a regular feature in Clocks Magazine, stresses the importance of considering replacement springs in the September 2024 issue, stating “it bears repeating that if you fit a spring that approximates to the original nineteenth century the movement will be overloaded”.1
Cleaning an open mainspring
If the original mainspring is functional, reusing it can save the cost of purchasing a replacement. In fact, finding an exact replacement for some older or rare clocks can be very challenging for the repairer.
That said, we certainly do not need to send more items to landfill sites. Reusing parts when possible reduces waste and the environmental impact of manufacturing new components.
Inspect the mainsprings during every servicing
Part of servicing a clock movement includes inspecting and cleaning the mainsprings. While open mainsprings are easier to inspect and work with, some repairers may be tempted to skip cleaning those encased in barrels. It’s important to learn how to open mainspring barrels for proper maintenance.
Mainspring barrel
Over time, the mainspring(s) can accumulate old oil, dirt, rust, and debris, which can impede its smooth operation. Removing the mainspring from the barrel or open springs from a movement allows for proper cleaning and lubrication, ensuring the clock runs efficiently.
Open mainsprings that have been serviced
Removing the spring also allows you to apply fresh mainspring oil evenly along the entire length of the spring. But that is not the only reason.
When Should You Replace the Mainsprings?
Removing the mainspring allows you to thoroughly inspect it for any signs of wear, fatigue, or damage that might require replacement. If the spring is in good condition but the hook end is cracked, it can be reused by cutting the spring and fashioning a new hook end. This will make the spring slightly shorter.
However, after a thorough cleaning, the movement will run more efficiently and require less power to run through its designed cycle, be it a day or a week, two weeks, and so, there may be little to no effect from a shortened mainspring. That said, the task of repairing a mainspring is best suited for an experienced clockmaker.
The most straightforward solution for the novice is simply to replace the spring.
Although they may appear set to some, this spring is perfectly usable
As a clock repairer, I rarely replace a mainspring. Even if a mainspring appears “set,” it often still has functionality. The important step is to return the spring to the movement and test it to ensure it meets the required standard by completing its designed cycle. If there is a significant loss, a running time of 2-3 days for an 8-day clock, and if there are no other obvious issues the mainspring must be replaced.
For some, ensuring a clock runs while preserving its original parts might take priority, even if the original mainspring cannot power the clock through its designed cycle. It is therefore essential to balance preservation with functionality.
Using a spring winder while working on a spring within a barrel
By carefully evaluating the mainspring’s condition and the specific needs of the movement, you can make an informed decision that respects both the clock’s history and its mechanical performance.
A clock spring barrel is a cylindrical component found in spring-driven clocks. Its primary function is to house the mainspring, which stores energy to power the clock.
The mainspring barrel works like this
Themainspringis a tightly coiled strip of metal that, when wound, stores potential energy. The barrel holds the mainspring in place and allows it to unwind in a controlled manner, releasing energy to drive the clock’s gears and ultimately the hands.
Mainspring barrel
The arbour, a shaft running through the center of the barrel, is connected to the winding mechanism by means of a gear. One end of the arbour accommodates a key, used to wind the spring. The other end of the arbour connects to the movement plate. When wound, the arbour twists the mainspring, storing energy. As the mainspring unwinds, it turns the barrel, which transmits power to the clock’s gear train. And that’s it!
A time-only clock made by Empire with a single barrel
A typical clock may have one, two, or even three barrels.
In a clock with a single barrel, the mainspring powers only a timekeeping train. Clocks with two barrels use one to power the time train and the other for the strike train. In clocks with three barrels, each barrel powers a separate function: one for the time train, one for the strike train, and one for the chime function.
Why remove the mainspring
Part of servicing a clock movement involves checking and cleaning the mainsprings.
Over time, the mainspring(s) can accumulate old oil, dirt, and debris, which can impede its smooth operation. Removing the mainspring from the barrel allows for proper cleaning and lubrication, ensuring the clock runs efficiently.
Removing the spring allows you to apply fresh mainspring oil evenly along the entire length of the spring. But that is not the only reason.
Mainsprings can weaken, crack, or break after years of use.
Removing the mainspring from the barrel allows you to thoroughly inspect it for any signs of wear, fatigue, or damage that might require replacement. If the spring is in good condition but the hook end is cracked, it can be reused by cutting the spring and fashioning a new hook end. However, this will make the spring slightly shorter. This task is best suited for an experienced clockmaker. That said, the most straightforward solution is to simply replace the spring.
If the mainspring is no longer functioning properly (e.g., losing power too quickly, damaged, or completely broken), it must be removed and replaced.
Broken mainspring
Regular maintenance, including removing the mainspring when necessary, helps prolong the life of the clock and ensures reliable running.
Remove the barrel from the clock movement:
Complete disassembly of the movement is necessary before working on the mainspring barrels. However, it’s worth noting that some German clocks are designed to allow the barrel to be removed without fully disassembling the entire movement, provided that only a broken mainspring needs to be replaced/repaired.
Ensure the mainspring is fully unwound before proceeding. If it is still wound, use a let-down tool to gradually release the tension.
The letdown key
The barrel consists of a cylindrical case and a cap. The cap is press-fitted in place and must be removed.
Hold the barrel in a gloved hand with the cap facing your palm (and the arbour between fingers), then give it a quick tap against a block of wood. The shoulder on the arbour inside the cap is enough to be able to supply even pressure to the centre of the cap and pop it off. This method ensures that there is no damage, and no scratches, plus it’s very simple to do.
Exercise caution to prevent bending or damaging the barrel. Although a screwdriver can be used to pry open the barrel, the risk of bending the cap or causing unsightly scratches is too great.
A mainspring winder
Attach the mainspring to a mainspring winder by securing the inner end of the mainspring to the winding arbor of the tool.
Mainspring barrel in Olie Baker spring winder, collar readied for the spring
Wind the mainspring slightly to loosen it from the barrel walls. Insert an appropriately sized mainspring collar and slowly unwind the mainspring into the collar and then gently remove it from the barrel.
Use thick leather gloves to handle the mainspring
Wind the spring again to remove it from the collar and then relax the spring for servicing.
The mainspring is inspected for damage, dirt, or rust. I use a Scotch-Brite scouring pad to clean the mainspring of dirt and debris. After cleaning, I wipe the spring with a soft cloth to remove any residue, and then lubricate it with Keystone mainspring oil.
After servicing, it is time to reinsert the mainspring into the barrel. Wind the mainspring tightly, place the collar back on, and secure the spring within it. Insert the collared spring into the barrel, ensuring the hook end catches on the notch inside. Finally, remove the collar and carefully unwind the spring into the barrel.
Using a mainspring winder such as one made by Olie Baker is the safest and easiest method for removing and re-installing the spring, as it ensures controlled release.
A mainspring can be removed manually, and there are plenty of YouTube videos available that demonstrate how to do it “properly.”
In Summary
It’s important to mention that there are specific barrel issues, such as broken catches or bulging barrels, which fall outside the scope of this article.
The mainspring barrel houses the mainspring and enables controlled energy release to drive the clock’s gears and hands. Proper maintenance of the mainspring, including its removal for cleaning and inspection, is essential to prolong the clock’s life. Regular servicing, including checking for wear and replacing damaged mainsprings, helps maintain the clock’s performance and longevity.
The example is a Fleet time and strike mantel clock from the 1930s. Fleet Time Company of Montreal, a company that was operating four short years, sourced movements from Germany prior to the Second World War. It was a very common mantel clock sold through department stores across Canada.
I like the step side design and the general simplicity of the clock.
Fleet Time case, refinished
The case was in need of refreshing but the movement looked to be in reasonably good condition and required a good cleaning and I was expecting some wear.
The movement was completely serviced with several new bushings installed. The mainsprings were removed, cleaned, and returned to their barrels.
Fleet time movement
In this movement, the mainsprings can be removed without disassembling the movement, handy for such things as replacing a broken mainspring assuming, of course that nothing else has been damaged.
During the testing phase, the mainsprings were partially wound. The intent was to see if the clock would run well. Once satisfied that the movement was running as it should I returned it to its case.
I wound the strike side fully and then wound the time side. Just as I was feeling resistance, CLUNK, the arbour turned freely. If it was a broken click or broken mainspring, either one could easily be replaced.
It has nothing to do with the force of winding a movement. Having a mainspring go bad with winding force from a key is rare, in my view.
But mainspring barrel teeth do not simply fall off.
Fleet time barrel
At times it is a mainspring but sometimes something far worse occurs.
It is not uncommon to find secondary damage to the movement, secondary or collateral damage due to the extreme shock that broke or bent the teeth and teeth cannot be straightened.
The main problem area beyond the barrel itself will be the second wheel and possibly the third wheel arbors, leaf pinions and pivots and/or damaged or missing teeth on the second and third wheels and bent or broken pinions.
Fleet second wheel, a bent leaf cannot be unbent
Is it fixable? Yes, but weighed against the value of the clock, it is just not worth it. It is much more cost effective to harvest parts from another movement.
Given the right equipment, it can be repaired. Once repaired a mainspring must be sourced and although the barrels may be identical, the mainsprings will likely be different.
The solution is locate a donor movement. In the meantime the clock has been put aside.
A mainspring’s purpose is to provide motive power for the wheels to move in a clock train. All mechanical clocks require a power source and the power source may be by weight or spring. Mechanical clocks that have mainsprings will have one, two, or three winding points which, once wound provide power for a clock’s designed cycle.
Each winding point or arbour is located on the dial face and requires a key (one key fits all arbours) to wind the clock. The mainspring is rated to provide power for a clock’s designed cycle, whether it be 1-day, 8-days, 15-days, and so on.
Sessions mainsprings cleaned and ready to be re-installed in the movement
Mechanical clocks are machines and over time machines wear out. When a clock will not wind up, it is time for a service. The service can be done if you have the skills and equipment otherwise you must depend on a professional clock repairer.
Should mainsprings be replaced during routine servicing?
Though not in the clock repair business I am aware that some repairers routinely replace mainsprings and, of course, the cost is passed on to the customer. Should they be replaced on a routinely or only when necessary?
As a general rule, I do not replace mainsprings when servicing a mechanical clock unless there is something fundamentally wrong with the spring(s). Obviously, there are situations where a mainspring must be replaced when it has failed in some catastrophic manner.
Broken mainspring which is not saveable
There may be occasions when there is too much surface rust or stress cracks on the mainsprings which will make them susceptible to failure and/or seizing and the prudent course of action is to replace them.
Ansonia time-only movement –Too rusted to save?
However, repairers reason that new mainspring(s) will extend the period between servicing and provide additional insurance for the repairer so that if the clock stops soon after servicing, issues other than the mainsprings are suspect.
Mainspring servicing
New quality mainsprings (American or German) also provide more power than the springs they replace and more power means they will continue to provide sufficient power for the clock through its rated cycle even if very worn.
Addressing wear by punching in a new bushing
The original mainsprings are often of better quality than a new spring. They may not have as much power as a new mainspring but many clocks, despite the fact that they are over 100 years old have springs that have more than sufficient power.
Once the movement is thoroughly cleaned, the pivots are polished and pivot wear is addressed there is less friction on the moving parts and therefore less power is required to drive the movement through it rated cycle.
Mainspring that is not salvageable
What if there are minor issues with the mainspring?
There are certain situations where a broken mainspring may be salvaged if the break is at the hook or loop end but not if it is broken in the middle. The mainspring can be shortened by two or three inches and after the repair, the spring will continue to provide sufficient power for the clock to run through its cycle.
What to do if your clock requires servicing by a professional
Should you bring your clock in to be professionally serviced ask plenty of questions. If it is recommended that the mainsprings be replaced, ask why, specifically. Once you receive a satisfactory explanation proceed with the repair.
New mainsprings, when the cost is upwards of $25 for each mainspring, will add substantially to the repair cost, something to be considered if the clock has little value. Of course, if it is to be repaired for sentimental reasons the cost is immaterial.
Mainsprings need not be replaced simply because they are old and “tired” and it does not require a lot of power to run a mechanical clock if serviced correctly.
This is Part I of a three (3) part series. In Part I I discuss disassembly and servicing the mainsprings. In Part II, the movement and in Part II restoring the brass case.
My wife found this 1910 Ansonia Crystal Regulator in the late summer 2018 while antique shopping. In the 1905 Ansonia Crystal Regulator catalogue it is listed as the Prism at a price of $29.00 which would have been a hefty sum at that time. (Flash is required to open the catalogue)
What a great choice! We were in a hurry and should have asked the proprietor to show us that it worked. We returned home and to our dismay, it was not running. As I said in an article published in Dec 2018:
A gentle push of the pendulum produces a few ticks and then it stops. I am not familiar with Brocot escapements and before I do anything I will research the movement before I disassemble it and give it a thorough cleaning.
Brocot visible escapement; in this photo, the brass is very tarnished
Just days old but I thought I would polish the brass
This is a truly beautiful clock with a visible escapement. What I have learned is this; don’t mess with a Brocot escapement. The stone pallets, which are made of garnet are very delicate and breaking one or both is a huge issue. The pallets are held together by melted shellac and cleaning them in an ultrasonic will loosen them as they are position sensitive.
It is now April (2019) and I have put this project off long enough. So let’s begin.
This not a particularly easy clock to work on. The pivots are smaller than a typical American time and strike movement which means closer tolerances. The strike side is rack and snail, that is, there are no helper springs and only one combination lever between the plates. Most strike parts are located outside the plates and the final assembly for the Brocot escapement also occurs outside the plates. There are two wheels with stop pins for the strike side. Setting them up can be a challenge.
Dissembling the case
To disassemble the case I wrapped two strips of painters tape on all four sides. Doing so prevents the glass from falling out. Beveled glass panels are difficult to replace and exercising care when working with the case will prevent accidents. Each glass panel can be as much as $75 by the time shipping is included and turnaround time can be as much as 2 months.
The first to come out is the gong assembly. One large nut secures the gong to the case and is accessible from underneath the base.
I chose to disassemble the entire case though it is possible to remove the movement without doing do. There are three screws at the 1-2, 10-11 and 6 o’clock positions though a long skinning screwdriver is required to get at them.
There are 4 large screws on the bottom and 4 on top. Unscrew the bottom 4 screws first. Once the base is off you will quickly realize the importance of the painter’s tape. To access the top screws there is one small screw underneath the top plate that must be released to access the 4 top corner screws. Patience is key if you work slowly the chance of error is reduced. Put the brass pieces and the glass panels in a safe place while working on the movement.
Mainsprings
The mainsprings are in barrels. The barrels are secured to the movement plates with 4 screws. The great wheel and the arbour are one piece. With a twist, the arbour can be removed from the mainspring.
There are three ways to service the mainsprings.
1) Find a temporary winding arbor and use it to unwind the mainspring on a spring winder.
2) Hold the barrel in one hand and pull the spring out with the other being careful not to kink or bend the spring. Once the spring is released from the barrel, unhook it and you are free to clean the spring. To put it back together, use a thick leather glove to hold the barrel, hook the hole end, and carefully rewind the spring back into the barrel.
3) Partially disassemble the great wheel and use the arbour without the gear in place. Special tools are required to separate the arbour from the wheel.
Olie Baker spring winder
Front of movement showing visible escapement
Back of movement showing rack and snail, hammer and rate adjuster
In Part II I discuss servicing the movement and in Part III, restoring the brass case.
The world of horology reveals an assortment of interesting expressions as well as the misuse of words and terms. For classic example; why do some refer to shelf clocks as Mantle clocks when a mantel is something you wear like a shawl or a cloak? Mantel, such as a shelf over a fireplace, is the correct term.
I want to focus on one very common expression. How many times have you the heard the expression, “it was running fine till I over-wound it”? I have heard it often enough on clock forum, Facebook sites and among acquaintances. It is an ubiquitous expression. Do not blame the last person winding the clock for they are not the cause of a so-called “over-wound” clock or one that stops mysteriously.
Over tightening
While it may be technically accurate that a mainspring can become damaged by repeated over-tightening that is, winding the spring until it is tight, and then continuing to tighten it more just to be on the safe side, there is another reason why this occurs.
Take a spring barrel like the one in the following photo.
Barrel and winding arbour
When the spring is wound it is coiled tightly around the winding arbour. The other end of the spring has a small hole which is hooked over a small stud, which is riveted into the interior wall of the barrel.
The hole allows the spring to be hooked to the inside of the barrel
The hole in the spring can become fatigued because of years of repeated “over-tightening”, and/or the stamped hook or riveted stud breaks free. “Over-winding” is not the reason.
A dirty movement
American open mainspring clocks “appear” to be “over-wound” because of a buildup of old oil, rust and dirt in the mainspring coil which causes the coil to stick and the spring to seize.
Clocks which might appear to be “over-wound” and non-working can be persuaded to run again by letting down the mainspring completely with a let-down tool, liberally applying mainspring oil and rewinding. This procedure is by no means a substitute for a good cleaning and it does not address other issues that may be causing the clock to stop but it is one step in troubleshooting your clock movement.
It is only when the movement is disassembled and the mainspring is removed from the arbour that you can examine the condition of the mainspring and decide whether to keep it or replace it. Dirt and old oil can be easily cleaned up. Light rust on a mainspring can be removed with emery paper or steel wool; heavy rust and the mainspring should be replaced. Inspect the spring for cracks or breaks. In many situations the mainspring can be saved.
In some cases the click can let go because the rivet securing the click becomes fatigued. For example, Sessions clocks have weak clicks and rivets. Inspection and remediation of a bad click is a typical procedure when servicing a Sessions clock.
Open mainspring click riveted in place.
Do not expect a newly acquired clock to have been serviced recently or at all unless the seller can prove it. Moreover, servicing a mechanical clock on a regular basis is an important part of ownership.
“Over-winding” is one of those terms that one hears quite often and is a very common myth.
Most refer to the name “Horse Crown” when describing this clock and it is easy to see why. Many would also consider it a Vienna Regulator style of clock. I have been putting off servicing this movement for a while and a long time has passed since it was properly serviced. So, let’s get started. First, some background.
Mauthe “Horse Crown”
The clcok was complete save for a missing bottom centre finial. I installed a new one shorty after I bought the clock
Clocks such as these are often missing not only a finial or two but the crown and other parts so this clock is in good condition.
Replacement middle finial
Year it was made and a history of the company
From my research, the trademark on the front plate tells me that the movement was made between 1895 and 1914 though the exact year of manufacture is unknown. Mauthe trademarks are very distinctive and from the trademark design, one can place the clock within a specific period of time. Unfortunately, the production number on the movement is a mystery as there is no known database for Mauthe clocks.
Trademark, production number, length of the pendulum (34cm), BPM (116) & patent number
Mauthe clocks have had a long and illustrious German history. In 1844 Friedrich Mauthe and his wife Marie founded the company in Schwenningen to produce watch parts. They were very successful through the years and diversified in several areas but after 1946 following the production of wrist watches the company gradually fell into decline.
This clock reminds me of what Forest Gump once said, “life is like a box of chocolates, you never know what you are going to get”
Now let’s open it up
The clock hung on my living room wall for three years. When I bought it I knew that it would eventually require servicing but there were so many other projects on the go, it could wait. The clock ran for several months at a stretch and there were months that the clock did not run at all. So, now that other projects have been completed the time is right for a thorough servicing.
Mauthe wall clock with new bottom centre finial
Forest Gump once said, “life is like a box of chocolates, you never know what you are going to get”. When inspecting any antique clock movement for the first time I have learned to expect just about anything.
As I move through any project my intent is not necessarily to correct mistakes of the past since they are an important part of the clock’s history but to ensure that past repairs do not cause me grief in the future. If it is a crude but functional and sturdy repair, I will generally leave it alone. I have learned that past repairs are part of the history of the clock.
When I took the movement out of the case I discovered something quite interesting. The dial is not original. Yes, it is a Mauthe dial but not for this clock. Two brass strips are fastened to each side of the front plate to accommodate a replacement dial. The added holes drilled into the side braces tell me that it once has a slightly smaller dial.
I am sure that those of you who are collectors have experienced the dilemma of identity
I am sure that those of you who are collectors have experienced the dilemma of identity. When I bought my first Vienna Regulator I began to realize that many parts were replaced over the years and it made me wonder what is original and what is not. It as an unwinnable argument and I have learned to accept the notion that it may not matter to me or to a casual observer who would not think of questioning whether a clock and its parts are original.
Two extensions, soldered to the sides to accommodate a replacement movement
But, let’s move on. A repair was made to the strike hammer which appears to have broken off at one point. Again, a rough but solid repair.
Hammer repair, you can see a pool of oil on the pivot to the left
The clock was coated in oil which was dripping down the plates. However, in terms of its general condition, there is surprisingly little wear. Perhaps the liberal application of oil had a hand in preserving the movement but I suspect that it did not run much over its life.
Mainspring servicing using the Olie Baker spring winder
The mainsprings are enclosed in barrels. I opened up the spring barrels to service the mainsprings. The mainsprings are in good shape with no evidence of rust. They cleaned up nicely. Broken mainsprings in German clocks can be problematic. Severe damage can result in missing mainspring barrel teeth and broken lantern pinions when the mainsprings let go, a challenge for any clock-maker.
Top plate removed
Strike side levers, escapement
The movement was disassembled and the parts were cleaned in my L&R ultrasonic cleaner. The springs and barrels were cleaned separately. All parts were washed in warm water and dried. Finally, the pivots were inspected and polished. Although this movement has a count wheel between the plates with levers much like an American time and strike there are no annoying helper springs to frustrate the re-assembly process.
After lubricating the mainsprings with Keystone Mainspring Lubricant, I put the movement together without the levers to check end-shake, meshing and the condition of the pivot holes. Two lantern pinions had some flat-spot wear but not enough to warrant replacement. Two pivot holes are slightly enlarged on the third and fourth wheel strike side but not so bad that they need immediate attention. If I were in the business of repairing clocks for a living I would bush those two and repair the lantern pinions.
Parts are cleaned & positioned, ready for the front plate
To reassemble the movement I secured the bottom front plate nuts to the back plate and then positioned the pivots into their holes working upwards. Once the pivots are in place on the strike side I attach the third nut loosely and continue guiding the pivots and the two lever assemblies in place. Unlike American movement which have larger pivots, care must be taken not to force the relatively small pivots into their holes.
Much like an American time and strike movement, the cam lever must be in the deep part of the cam while at the same time the count hook is in the deep slot on the count wheel. I made a note of the position of the stop wheel beforehand and in so doing managed to correctly position it on my first attempt.
I generally run a movement for an hour or so without lubricant to determine if everything is functioning properly. No point in oiling the movement repeatedly if it has the be dis-assembled to correct an issue. Once I am satisfied that the movement is running as it should, I apply oil to the pivot holes.
Having the movement out gave me an opportunity to clean up the case, paint the gong mount and movement rail and give the entire case two coats of shellac (traditional 1 lb cut). The movement is now reinstalled in the case.
With respect to my comments concerning the pivot holes and lantern pinions, putting the movement on a shorter 2-year cycle will enable me to monitor wear.
I had just completed servicing this German Mauthe time and strike wall clock and everything seemed to be going well. It was keeping good time,striking on the half hour as it should and maintaining a consistent an 8-day cycle.
During my regular Saturday clock winding ritual, I decided to begin with this clock. I inserted the key into the strike side arbour, began to turn the arbour and “bang” went the mainspring. The winding key almost took my thumb off.
I think I am going to lose that nail
Ignoring the excruciating pain I just had to investigate the problem. I took the movement out of the case and took the dial off. Of course, I feared the worst. A sound like that is never good. The barrel seemed undamaged, the teeth were intact, no bent arbours and there did not appear to be any collateral breakage.
Aha!, there it is, a loose click spring. The click released when there was not enough tension on the click to hold it firmly to the ratchet wheel.
My fault entirely. When I dis-assembled the movement I bent the click springs out of the way and did not recheck the spring’s tension. When I re-assembled the movement the click on the strike side was evidently loose but it looked tight enough. I wondered why the strike side ratchet sounded “tinny” but I thought nothing of it. Now I know.
Clicks on Mauthe movement
I increased the tension of the click spring. To be on the safe side I checked and tightened the time side one as well. Both sides now have that reassuring click-click sound. As you can see in the above photo It is not the best click spring design.
A reminder to anyone working on clocks that potential (or stored) energy in the form of powerful mainsprings can be dangerous. All is well, lesson learned. But my poor thumb!
Some folks collect clocks without actually working on them. Collecting clocks and repairing them are two very different things. I know people who would gladly send their clocks out for servicing and don’t seem to mind the extra cost. I like to do my own work.
If you work on your own clocks or service clocks for others you know how important it is to ensure safety at all times. Servicing a clock movement requires that you disassemble it completely and safely. There are specific tools designed not only to make life easier as a clock repair person but will ensure your safety at the same time.
Before taking the pins or nuts from the movement plates there are important steps you must follow to ensure your safety working with movements. There is a minimal threat of injury working with weight driven clocks (unless a weight drops on your foot) so the following information pertains to spring driven clocks be they open mainsprings or springs contained in a barrel. The let-down tool is designed specifically for spring driven clocks.
Click, click spring and ratchet
The letdown key is engaged prior to releasing the click
Some clock movements from French, English and German clocks, for example, contain mainsprings within a barrel, safer than open mainsprings. If the spring lets go in a barrel there is still a risk of damage to the gear teeth and wheels however the break will be contained within the barrel itself. The letdown key is used to release the power of the mainspring into its barrel.
The flat clamps (upper left in photo below) are for those open mainsprings which do not leave a lot of working room. Otherwise, the round clamps are good for most applications. Prior to working on a movement the mainsprings must be letdown or restrained in their clamps.
C-clamps used to contain the power of the mainspring
A flat C-clamp is wrapped around the mainspring as you can see in the next photo.
Mainspring contained in a C-clamp
Once the mainspring is safely contained you can work on it with a spring winder, like this spring-winder from Olie Baker .
Mainspring servicing using a Olie Baker spring winder
Here’s how it works. There are four pieces in the let-down set. There are 3 chucks in sizes #5-6, #7-8 and #10-12 plus the handle. Choose the size that fits the winding arbour of your movement. Then insert the let-down end with chuck into the winding arbour. Turn it until the mainspring is compressed. Fit a clamp around the mainspring. Once the clamp is secure around the mainspring release the click spring with a small screwdriver and push it out of the way. Once the click spring is out of the way move the click away from the ratchet while firmly holding the let-down key. The power of the spring will be transferred to the key. Allow the spring to gradually release its power by letting the key handle spin gently within your hand. There, the mainspring power has been restrained and you will be able to proceed with dis-assembly.
Your journey into the world of clock repair requires essential tools The let-down set should at the top of the list. Always minimize the risk of injury by restraining the power of the mainsprings. The letdown key is the safest method of letting down the mainsprings.
An antique clock stopping unexpectedly can be frustrating, especially if it has been running smoothly for years. However, a stopped clock doesn’t always signal a major problem. In many cases, the issue can be resolved with a little troubleshooting and basic maintenance. Whether it’s a cherished family heirloom or a recent addition to your collection, understanding the possible reasons behind its stoppage can help you decide on the best course of action to bring it back to life.
Perhaps you’ve recently acquired a mechanical clock—whether inherited, gifted, purchased at an antique store, bought online, or one you’ve had for a while—and, for no clear reason, it has stopped working.
Categories of Clocks
There are four general categories of clock movements; quartz, electro-mechanical, electric, and mechanical. This post focuses on mechanical clocks, whether antique or vintage and if your mechanical clock has stopped, I may be able to help you get it working again.
Running Time
It may surprise some that mechanical clocks require regular winding. Eight-day clocks need to be wound once a week, while 30-hour clocks require daily winding. 31-day clocks only need winding once a month, and 400-day clocks, also known as anniversary clocks, are wound once a year. Additionally, many German and a small number of American clocks run for 14 days before needing a wind.
Kundo Standard 400-day clock winds with a key once per year
Arthur Pequegnat Moncton, 14-day time-only clock
Winding a Clock Movement
What does winding a clock actually mean? It means providing enough power to a mechanism that will allow it to run for its designed cycle.
For example for clocks with mainsprings, winding a mainspring implies turning the key until the clock winds no further. Time and strike clocks will have two winding arbours, chiming clocks generally have 3 winding arbours.
Clocks with weights have one, two, or three winding points. Absent the odd exception, a time-only clock will have one winding point, a time-and-strike clock will have two, and a chiming clock will have three. If there are no winding holes on the clock face, it is a weight-driven clock and the weights must be pulled up by hand.
In the case of clocks with mainsprings that provide the motive power for the time, strike, and chimes, wind each arbour until resistance is met and you cannot wind any further.
One key will fit all the arbours except the regulator arbour (on clocks that have this feature) which requires a smaller key. Clocks that have a regulator arbour originally came with a double-ended key; the smaller key is for the regulator.
Clocks generally wind clockwise but it is also common to find winding arbours that must be wound counterclockwise.
Over-winding
The idea of overwinding a clock is a myth. If a clock stops after being fully wound, it typically indicates that dirt, old oil, or grime on the mainspring has caused it to seize. Even if the mainspring, once unseized, has enough power, it still needs cleaning, which requires disassembling the movement and checking for other potential issues.
A clock in good working condition should complete its full cycle, whether that’s 30 hours, 8 days, 14 days, 31 days, or any other duration.
Winding arbors on a Seth Thomas mantel clock (arrows). The arbour over the 6 requires a smaller key to regulate the clock
Why Has My Clock Stopped
First and foremost, all clocks require motive power. Winding a clock stores potential energy in the mainspring, which is gradually released over a designed period of time. This energy is regulated by the escapement, a mechanism that controls the release of the energy in small, consistent increments, ensuring the clock keeps accurate time. Weights resting on the bottom of the baseboard will stop a clock and a completely unwound spring-driven clock will not run.
Is the clock in beat? Put your clock on a level surface. Listen to the tick and the tock of your clock. Try to minimize the sounds in the room you are in so that you can listen closely to its rhythm. It is in beat when its ticks and tocks are even….tick…tock…tick…tock…, and is out of beat when they are uneven, either, tick….. tock or tock tick…… Put another way, there must be an equal amount of time between the ticks and the tocks. When a clock is out of beat, it will not run, or it will run for a short time and stop. A clock’s beat must be regular to work properly.
Is the clock level? There are two ways to put a clock in beat. The first is to tilt the clock sideways, one way or the other, and listen for the beat to even out. When the beat is even, prop the clock to stay tilted that way. If it is a wall clock move the bottom section from side to side till you hear a steady beat. Now it will run in beat but it will obviously not look good.
Adjusting the crutch Adjust the crutch to one side or the other until the beat is even. The crutch is the rod that extends down from the pallets which rock back and forth on the escape wheel. The pendulum rod passes through either a loop (called a crutch loop) or a forked foot at the end of the crutch as indicated in the photo below. Incidentally, that rod needs to be in the middle of the crutch loop and can’t be tight inside the loop nor too loose. The crutch is attached to the pendulum leader which is then attached to a post with a suspension spring. Other mantel clocks require similar adjustment to the crutch and instructions may be provided on a label or a pamphlet that came with the clock. A clock with a balance wheel or lever-type escapement rather than a pendulum will operate on a non-level surface.
American made time and strike
Have repairs been done recently? Unless you had a friend fix your clock most reputable clock-makers will offer a warranty, typically 6 months to a year. If your clock stops within that time frame, contact the clock-repairer who may offer a few suggestions in the form of adjustments, over the phone before taking it back to the shop. If it still does not work have that person take a look at the clock.
Do you have the correct pendulum? Other than the winding key, it seems to be the item that gets lost the most. If lost or misplaced, ensure you buy a pendulum that is correct for your clock. One too light may mean that it does not run at all, too heavy and the centre of gravity is lowered and the clock might run too slowly. Clock suppliers such asPerrin or Timesavers will have the correct pendulum for your clock.
Pendulum bob with an adjuster for a French time and strike
Something is broken? If there is no resistance when turning the winding key, the mainspring has broken or a click has let go. If the mainspring winds but releases in your hand, the most common cause is a broken or worn click spring. This is a repair that requires removing the movement from its case, taking it apart, and replacing the worn or damaged part. If you are skilled with that kind of repair, go ahead and fix it, if not, a specialist is required.
A loud BANG when you turn the key indicates the mainspring has broken or let go. It may not be as simple as replacing the mainspring. If the mainspring breaks it might have taken out other parts with it such as pinions and gear cogs. This is called collateral damage. An inspection and a full servicing of the movement is the only solution. Occasionally a broken mainspring is the only problem but the broken spring must come out of the barrel. Some movement designs allow the barrel to be removed without disassembling the mechanism. Whether the barrel is removable or not, a correct mainspring must be sourced to replace it and installed in the barrel which is a job for an expert.
The mainspring inside the barrel may also have become unhooked. This could occur if the clock was wound backward or if the hooked end of the mainspring is split or broken. To address this, the clock will need to be disassembled, the spring barrel opened, and the cause of the unhooking identified. In some cases, a replacement mainspring may be necessary.
For time and strike clocks with open mainsprings, the break may be on one mainspring or both. The clock must be completely disassembled, mainsprings replaced, the movement inspected for other issues, reassembled, and tested.
Sessions click, brass spring, and ratchet
Why does my weight-driven clock stop? Ensure that the weights are in their correct location. If it is a new acquisition of a grandfather clock the three weights have a specific location. Look underneath the weight shells for marks indicating their location “L”, left side, “C”, center and “R”, right side. If there are no markings, use a scale to determine the one that is the lightest weight and put that on the left side.
Ridgway grandfather clock
When bringing up the weights to the top of the clock be careful that they are not run past their stops. You should have a full view of the weights on a weight-driven clock once wound.
Antique Ogee clocks and other weight-driven shelf clocks often lack their original weights, as these have been lost or misplaced over time. Eight-day clocks typically have heavier 8 or 9 lb weights while 30-hour clocks have lighter 2 1/2 lb or 3 lb weights. Incorrect weights for these clocks will cause them to stop.
Is the weight cord or the brass cable binding in any way? The cord or cable should be just long enough to accommodate the weights. A cord or cable that is too long will bind while being wound and stop the clock.
Gustav Becker two-weight wall clock requires a winding crank
Some clocks like weight-driven Vienna Regulators can be adjusted by a transverse regulating screw assembly where the crutch inserts into a slot in the pendulum. Turning a screw in one direction or the other will correct the beat.
Final thoughts
In conclusion, if you encounter a unique issue not addressed here, it’s advisable to consult a professional clock repairer or someone with expertise in mechanical clock repairs. Working with mechanical clocks carries a certain level of risk, as the power stored in the mainsprings can cause injury if not handled carefully. On the other hand, weight-driven clocks generally present less risk.
Although this article may not cover every possible scenario, I hope it has provided you with a clearer understanding of your clock’s issue and how to approach its resolution.
There is no maker’s mark anywhere on the case or the movement
The clock is an unsigned 8-day carriage clock in a rectangular brass case. This attractive little clock has a white enameled dial with Roman numerals, blued steel hands and a spring driven time-only movement with platform lever escapement visible through the top beveled glass. The brass case has 4 beveled glass panels complete with a fold-down travel handle.
In taking the movement apart to clean it I can see “73” stamped on the bottom of the case, the case handle, the door edge and 2 or three places on the movement and the letter “B” on the back of the front plate but no maker’s mark. What do the numbers mean? I think it is an internal production stamp. Thousands of these generic carriage clocks were made and I may never know the maker. The only taper pins on this movement are those that attach the dial face to the movement. However, judging from what see and its general construction I would comfortably date this clock to the 1880s.
The movement plates are secured by screws rather than taper pins. Older carriage clocks would have taper pins securing the movement plates. This clock would have been produced for the English market since it has “S”and “F” stamped on the escapement (Slow and Fast). The key has “France” inscribed on it so if it is original, then the clock is French.
Unsigned French Carriage Clock
Time-only carriage clocks are relatively easy to work on although the platform escapement takes a extra care. I chose not to service the escapement at this time.
First, let the mainspring down to release the power. If you take a wound clock apart it can injure you. Some of the compression points between cogs can have a very high gearing so even a weakly wound clock has the capacity to trap or pinch your fingers as well as throwing out and damaging components. I use a let down key that can be purchased at any clock supply house.
Carriage clock platform escapement
Movement side view, re-assembled
Taking the movement out of the case involves releasing 4 machine screws in the base. I use several elastic bands to keep the glass in place while I lift the sides and door off the base. When holding the clock firmly observe the effect of loosening the screws. The pillars have become loose and the glass can now move a little in the frame. If you unscrew all the screws completely without understanding that the glass is loose, it is too easy for the glass panels to slide out and break. They are not easy to replace! I’ll describe my work on glass cleaning later.
There are two screws which hold the base to the movement. Unscrew those and proceed to take off the front face. The enameled face is secured by 4 taper pins. In my case they were difficult to get out so I decided to take the back plate off the movement to allow my pliers inside to release the pins. Removing the platform escapement requires releasing 4 very tiny screws. A precision slotted screwdriver is absolutely necessary. It is best to unscrew all 4 together and leave them in place once off the movement so you do not have to fiddle with them when reattaching the escapement later, unless, of course, you intend to service the escapement.
Back plate after a cleaning
I then separate the plates and inspect the wheels, pinions, pivots and pivot holes. I found a little bit of play in two pivot holes only observable with a loupe but not enough for bushing work. I polished the pivots, pegged the pivot holes and cleaned the wheels, plates and other pieces except the platform escapement in the ultrasonic cleaner.
Assembly of the movement is relatively simple as there are so few gears. Attaching the hour hand was interesting, however. Both the hour and minute hands are pressure fit, but the hour hand was a challenge because I had to use a screwdriver to push the hour shaft forward (gently) through the clock face while simultaneously attaching the hour hand. It was very tight. After a number of tries I managed to press it in securely.
It is actually quite small
Back to the glass. It is also important to put each panel back where it belongs. I discovered that there is a top and bottom orientation to each glass panel, they are cut so fine! There is enough resistance if you try to put the wrong end into the channels you will encounter difficulty. Each glass panel is taken out and cleaned with Windex and, of course, put back exactly how they came out.
Once everything is assembled the clock is oiled, wound and the time is set. Polishing the brass case is the final step. Brasso was used to clean up the brass and bring the clock back to its former glory.
We often cruise the HiBid sites. While they may be wholly Canadian I am sure there are similar sites in the US. HiBid are a hosting service for antique online auction companies and from time to time clocks come up on estate sales.
One day in early February 2017 we were on a Nova Scotia HiBid auction site and noticed a Jauch drop octagon with a PL42 movement. I made what I thought was a reasonably good bid. We had errands to run that day so I just left the bid, got home later and realized and surprised that I had won. It was a good purchase. After running for several weeks I opened the case up and discovered its hidden secret.
Time-only Jauch movement
The clock easily runs a full 8-day cycle but it gains about 5-7 minutes at the beginning of the cycle and loses the same at the end of the cycle. A dramatic difference! A properly functioning clock is designed to run at an acceptable rate of + or- 1 minute per week but this depends on adequate power to the escapement with very little fluctuation in that power.
Scored pivots and worn barrel arbor holes are real issues for this movement. The pivots are small, a light touch with a buff stick and a minimal polish along with pegging and round broaching the holes should be the first steps in reviving this clock. Bushing work is also quite possible. The barrels are another matter. If worn, they require bushing. The cap is too thin to bush without making a thin flange or leaving the bush a bit proud and peening both sides. The barrel is narrow and it is said that they really get the wobbles when worn.
This is an inexpensive German movement but finely made and well engineered. An overhaul should result in a good long run.
I took the movement apart and discovered two things. One, it needs at least 3, perhaps 4 bushings and secondly, there is a significant gap in the barrel cap as seen in the photo below.
Barrel cap showing a wide gap caused by wear around the arbour, weak point of this movement
Front plate is removed showing going train
The real issue for me is the barrel cap. I can attempt to bush the cap but the bushing would likely not hold unless it is peened. The gap is causing an unbalance in power transmitted through the gears as a result of the wear. The soft brass barrel cap is definitely a weakness of this movement. The result is the erratic running described above and a wobble in the pendulum. I contacted a gentleman in Arizona who would be prepared to correct the wear by installing two new bushings on the gear side and cap of the barrel. The cost is 1 1/2 times the value of the clock so I have decided against that option. It is just not worth it!
1 Day Later
I installed 3 bushings. The front side of the escape wheel arbour, the front side of the second wheel and the minute shaft. I re-assembled the movement, oiled it, adjusted the pallets, reinstalled the worn barrel and have put the movement back into its case. It is now running and in the next week or two I will see what effect new bushings will have on the running of the clock. My hope is a marginal improvement given the worn barrel.
A barrel repair will have to wait until I have the proper tools.
Regular reader and contributor JC suggested a few more clock terms I thought readers and fellow horologists might find interesting.
My source for this article is the Watch and Clock Encyclopedia by Donald de Clarke, published by Bonanza Books (1984) which is still available on Amazon.
Gridiron pendulum: A pendulum consisting of alternating steels and brass rods coupled together to compensate for downward expansion so that the centre of oscillation of the pendulum remains consistent with changes in temperature, invented by John Harrison in 1725.
Gridiron pendulum on a Junghans Crispi wall clock
Broaches: To broach is to open and enlarge a hole. A Broach is a steel cutting or smoothing tool with a tapered or parallel sided edge used to cut or “finish” holes in a clock plate. Used to enlarge and then finish (smooth) a newly installed bushing on a clock plate.
A set of Swiss made smoothing (or finishing) broaches
Motion Works: The train or wheels of a clock directly connected with the hour and minute hand.
Great wheel: The teeth that form part of the barrel of the going barrel. It is also the wheel to which the mainspring is attached.
The motion works of a clock; the largest wheel on this movement is the great wheel (Pequegnat Clock Co.)
Maintaining Power: A method to maintain the driving power while the weight is being lifted or mainspring with fusee is being wound. In effect keeping the mechanism going while winding.
Weight driven movement with maintaining power, (unmarked Vienna Regulator)
Huygens Endless Rope Drive: It is a method of providing maintaining power to drive the clock while the weight was being raised. The endless cord passes over pulley A which is attached to the great wheel and supports the driving weight B, it then passes over pulley C which has a ratchet to support small weight D. As cord E is pulled down to wind the clock ratchet C turns under it’s click to raise weight B which continues to drive the clock as it supplies torque to wheel A. This ingenious system is found in some 18th century long-case clocks.
Huygens endless rope
Locking Wheel (or Count Wheel): A count wheel is the wheel that determines the number of blows to be struck in striking mechanisms.
The left wheel with notches is the count wheel
Ratchet wheel: A toothed wheel into which a click engages permitting the wheel to revolve in one direction only.
Toothed ratchet wheel and click
Cam: Usually a disk so that upon revolving it transmits movement to or exerts pressure upon a connecting unit.
Arrow showing location of a cam, the fly is located in the upper right
Fly: Often called the governor or controller of a chime or strike train. It is the last piece in a train of wheels.
The language of the clock world always amazes me. There are a plethora of other clock terms that I will be happy to explore in future blogs.
In a precious article I wrote about my frustrations getting this clock to run reliably. No matter what adjustments I made it ran poorly.
“You’ve got to be very careful if you don’t know where you are going, because you might not get there”, Yogi Berra
This time and strike movement (Hermle?) has been out of its case and lying in drawer for the past year or so. When I met the seller in a parking lot some time ago as I handed him $20 for this Dugena mantel clock he climbed into his car he said, “I hope you don’t expect much for $20; it’s not perfect”. Well, it’s not perfect.
It was keeping poor time, losing an hour or so a day but I thought, what a great clock to practice on and practice I did.
Oiling the movement had no effect. Issues? A weak spiral spring, a worn jewel on the floating balance, a power issue associated with a weak mainspring or perhaps pivot wear. I disassembled the movement several times and serviced the mainsprings. I had an issue re-hooking the strike side mainspring and so, discouraged, I put it aside.
Dugena time and strike German made mantel clock
Dugena – is it a clock company?
Dugena was a German retail clock name only, a marketing name, not a maker of movements or cases. Dugena was a registered cooperative society, a “Genossenschaft”, that bought clocks from other makers to sell them under their own brand. A brand name for a retail chain more or less.
Dugena floating balance
The clock runs slow, this bent spiral spring does not help
Floating balance clocks are much more accurate and above all, they do not have have the disadvantage of the pendulum; these clocks work even when the case is at an oblique angle
A great invention – the floating balance
The floating balance movement in this clock could have been made by anyone; Urgos, Jauch or Hermle perhaps. Hermle is likely since it was one of the leading companies using the floating balance escapement. The floating balance was invented in the 1930s but it took till 1941 for the patent application to be registered. It took another 10 years after that for the patent to be granted slowed by the war years and the challenges of industry recovery following the Second World War.
The floating balance was a great invention. Floating balance clocks are generally more accurate and above all, they do not have have the main disadvantage of the pendulum; they will work even when the clock case is at an oblique angle.
Time and strike movement, maker unknown
Back to the the clock
Months passed. I took the movement out, looked at the strike side barrel a second time, popped the barrel cap off and using pliers gave the inner part of the mainspring a turn and it hooked onto the catch. Success at last. The mainspring barrels can be removed without dis-assembly of the movement, so, in it went. Despite my minor triumph with the strike-side mainspring, straightening the spiral spring and adjusting the balance wheel to its fastest set point, the clock ran only marginally better. The only consolation is that although it runs 5 minutes slower per day it runs a full eight day cycle.
Despite the minor disappointment it has been a productive learning experience but I am inclined to put it aside as I have other projects on the go. Every time I think about the issues I am having with this clock it always comes back to the balance wheel.
In this age of everything electronic, it may surprise some people that a newly acquired mechanical clock bought at the local garage sale, flea market or antique store needs to be wound on a regular basis. Winding a mechanical clock takes a level of care but a few simple guidelines should have you on your way.
Here’s how to wind an antique or vintage mechanical clock correctly. By following these tips and guidance, you’ll gain the skill and confidence needed to wind your clock properly and maintain its functionality.
Let’s begin by discussing some basic terms.
Winding Arbours or Winding Points and Their Function
On your clock’s dial (excluding cable-driven tall case clocks or any clock that has pull-up weights), you will notice one, two, or three holes, known as “winding arbours” or winding points.
A typical German mantel clock
For example, a clock with one winding hole is a time-only clock. Two winding holes typically indicate a time-and-strike clock. These clocks strike the hour on the hour and may also strike on the half-hour, either on a bell or gong.
Each arbour serves a specific purpose, and the number of winding arbours indicates the number of gear trains (or sets of gears) in the clock.
Clocks with three winding arbours chime on the quarter-hour, producing a musical tone. On such clocks, the center arbour winds the time train, the left arbour winds the strike train, and the right arbour winds the chime train.
On some clocks, there is a smaller hole on the clock face near or above the 12 o’clock position. It is also an arbour, but a smaller one used for regulating the speed of your clock. If you have a double-ended key, the small end fits that arbour. Some clocks will have the regulating arbour located under the centre cannon where the hands are attached.
The Difference Between the Terms Strike and Chime
A strike or a chime is simply the clock sounding the time. An antique or vintage “time and strike” clock indicates the hour by striking once for each hour or using a two-tone strike, such as a Normandy or “Bim-Bam” strike.
On the other hand, a chime is a musical tone, and a typical musical tone found on most clocks with three winding points is the Westminster chime. Some clocks provide more choices, such as the Schatz W3 bracket clock, which has 3 musical tones: St Michael’s, Whittington, and Westminster.
On older clocks, there may or may not be an additional strike on the half-hour. Older antique clocks from the mid-1800s, for example, typically do not strike on the half-hour to preserve the wind on the strike side.
Typically, striking clocks have two winding points, while chiming clocks have three.
Where Winding Points Are Located
On this spring-driven, Seth Thomas mantel clock (photo below), the left arbour, indicated by an arrow, winds the strike side, and the right arbour, the right arrow winds the time side. The smaller hole just below the centre cannon is for regulating the clock using a double-ended key.
Winding arbours on an antique Seth Thomas mantel clock
On the Ingraham clock (photo below), there is only one set (or train of gears) that indicates it is a time-only clock, hence the single arbour or winding point. The barely visible, smaller hole in the loop end of the “2” on the number 12 is for regulating the clock.
Winding arbour on an Ingraham Nordic banjo clock
If the striking sound is bothersome or disruptive to guests, you can simply wind the time side only—the clock will continue to run normally without engaging the strike mechanism.
However, to ensure even wear and proper maintenance, it is advisable to wind both sides of a striking clock.
The Running Time or Cycle of a Clock
Most clocks are designed to run for eight days. Some older clocks run 30 hours, and others run as long as 30 days on a wind. Still others, such as anniversary clocks, will run 400 days on a wind.
Double-ended Key
For eight-day clocks, winding once a week ensures the clock continues running smoothly. Establishing a routine, such as winding your clock(s) on the same day each week (a Saturday, for example), is a helpful habit. It’s also a good idea to make occasional adjustments to your clock, such as fine-tuning its speed to account for seasonal changes. You can find more details in an article I wrote about regulating your clock.
Clock Keys
It is common for a newly acquired clock to come without a key, but this is nothing to worry about. If it does have one, it is usually a replacement. Finding a clock with its original key is quite rare. The key that accompanies the clock is likely to fit, but if your clock has a speed adjustment arbour (marked F-S) on the dial, typically located near the top, it should have a double-ended key.
If your clock has a one-ended winding key and a speed adjustment arbour is present, the key is not original to the clock. Double-ended keys are necessary because the speed adjustment arbour is considerably smaller than the winding arbour.
Key Size and Type
All mechanical clocks require a winding key, like the one shown below. For those clocks that have winding cables, a winding crank is required. Winding cranks will be covered later in this article. The exceptions are alarm clocks and some carriage clocks, which have built-in winding keys. Keys come in various sizes, so it’s important to have the correct size for your clock’s arbour. The key should fit snugly without being too loose.
If your clock came without a key it can be purchased at any clock supply house, such as Perrinin Vancouver, Canada. Timesavers and Merritts are clock suppliers in the USA, where keys can be purchased.
Ingraham Huron winding key. Home-made but functional and over 120 years old
Over-winding a clock is a common myth. A clock which “appears” to be over-wound seizes because of a buildup of old oil and dirt in the mainspring coil
Winding Your Mechanical Clock
If the dial is covered by a glass door, open it to access the clock face. Insert the key into one of the winding arbors, and use your non-dominant hand to steady the case while winding. To protect the finish, it’s a good idea to wear a cotton glove on your non-dominant hand.
Next, turn the key clockwise. If it doesn’t turn clockwise, try turning it counterclockwise. Some clocks wind differently, so this is normal. Avoid forcing the key; apply minimal pressure and continue winding until you feel resistance. Once you encounter resistance, stop winding and do not force the key further.
Below is a clear example of a previous owner using excessive force to wind the movement in the wrong direction. The right spring barrel has become unhooked from the main wheel, which only happens when significant force is applied while winding in the opposite direction.
If you lose the key, simply purchase a replacement. Never use pliers or any other hand tools to wind a clock, as the arbours can be easily stripped.
Chinese clock movement
The “clicking” sound heard while winding the arbour is the click engaging the ratchet on the mainspring. The ratchet’s purpose is to secure the mainspring in place with each turn of the key.
An 8-day clock usually requires about 14 half turns of the key as the arbour does one complete turn per day.
Mainspring ratchet and click.
Allow the key to gently return to its click. On the rare occasion that the click slips or breaks, resist the urge to release it quickly. Instead, let the key slowly unwind in your hand to prevent potential damage to the teeth, gears, and even your hand. Letting the key go free suddenly can cause collateral damage to other parts of the movement.
The myth of overwinding a clock is common, but a clock that “seems” overwound actually seizes due to a buildup of old oil and dirt in the mainspring coil, which causes the coil to lock or stick. Regular servicing of a mechanical clock is an essential part of ownership and helps prevent future mainspring issues.
Clocks with Weights
Not all clocks use springs — for example, grandfather clocks and one-day ogee clocks are weight-driven. On these clocks, the weights must be raised to the top to begin the weekly time cycle. This can be done either by inserting a crank key into the winding arbor on the clock face or by manually pulling the chains to lift the weights.
For clocks with winding chains, gently pull down on the shorter side of the chain until the weight reaches the underside of the wooden seatboard, stopping at the weight stop bar. Repeat this process for the remaining two chains if it’s a chiming clock. Allow the chains to do the work — do not assist by lifting the weights at the same time. Pushing up on the weights could cause the chain to slip over the winding gear teeth or become unhooked. To protect the brass finish on the weight shells, wear cotton gloves while steadying the weights as they are pulled up.
For tall case clocks with cable drives, use a crank key to wind them by inserting the key into each winding hole on the clock face. Turn the key slowly until the weights are raised to the top.
All three weights on a chiming grandfather clock descend more or less together through the week.
On older tall case clocks with weights hidden behind an access door, open the door to observe the weights as they rise when you wind the clock. As the weights near the top, slow down and stop when you feel resistance.
Thirty-hour time and strike or one-day clocks are typically wound with a winding crank inserted in the dial face winding points once per day. Wind the weights to the top of the case at approximately the same time each day.
Final thoughts
In conclusion, take pride in your mechanical clock and the craftsmanship it represents. Wind it regularly, care for it properly, and have it serviced when necessary. Even if you prefer not to keep it running, cherish it as a remarkable piece of horological heritage.
For visual learners who prefer to see the process in action, I’ve created a helpful video demonstration showing exactly how to wind a clock. You can watch it here:
This is Part II of a multi part series on the Sessions Westminster A chiming mantel clock.
Side view of Sessions Westminster A
Inside the plates they are a conventional Sessions clock. Outside the plates is an entirely different story
Sessions Westminster A clocks are true chiming clocks that play the Westminster chime sequences on the quarter hours and strike the hour count on the hour. The unique design combines the chiming and striking functions in one train powered by a single main spring. Between the movement plates these movements are very similar to other Sessions non-chime (strike only) movements. The going (time) train is controlled by a basic recoil escapement with the strip pallets or verge located between the plates. Inside the plates they are a conventional Sessions clock.
Outside the plates is an entirely different story. At the front of the movement one will notice that this is a rack and snail strike train but it has TWO racks and TWO snails. A look at the back of the movement reveals a small cam in the middle of the plate and a large “player drum” or pin drum. The two racks working together with the little cam and the player drum, which can shift outward to play chimes or inward to strike the hour, is what makes it all work. The chime sequence is self‐synchronizing and with so few working parts, once setup correctly this can be a relatively trouble free movement. (Source R. Croswell’sTaming the Sessions Two Train Clock)
This clock requires servicing for two reasons;
It runs for several minutes or an hour or so and then stops
The striking and chiming is very erratic. It might strike 4 o’clock one hour and 9 o’clock the next and the hammers “hang up” during the quarter hour chime.
There are a number of “exterior” parts that must be removed before separating the plates
Dis-assembly of the Westminster A is conventional however there are a number of “exterior” parts that must be removed before separating the plates. The regulator gearing, verge, drum assembly, hammers and racks as well as other parts are removed one after another. The additional parts add considerable complication to the movement and can lead to issues when servicing. I will describe two particular issues I have encountered in the process of working with this movement. I believe these issues, which I will describe later, are likely what frustrate most clock repair persons when working on the Westminster A.
Rear plate showing regulator, verge and chime drum. Clamp on mainspring
I chose to leave the mainsprings in while taking the movement apart though I contained the power using C-clamps. On this clock the mainsprings can be removed without dis-assembly. This allows the repair person to easily service the mainsprings or the clicks (which are notoriously bad on Sessions clocks generally).
Unfastening the drum and hammer assembly went without issue since there are only two bolts securing it to the plate.
The 2 racks, a unique feature, work together to produce the strike. They are located one on top of the other and are secured to a post.
Two racks stacked on top of each other. The post on the right accommodates two springs
Taking them off requires releasing a pressure washer on the top of the post. They came out easily. However, one rack is missing a return spring which might partly explain the erratic striking of the clock. Such a simple thing that may make a big difference. I may have to buy or fashion a spring.
Rack with spring
Rack without spring. The spring clips into the hole on the rack arm
Specialized tools are needed to remove some parts. Those I don’t have
Two issues.
One, I could not remove the hub supporting the gathering pallet pins seen here. It’s unfortunate because there is more lateral movement of the arbour that I am comfortable with which tells me that a bushing is required. I did not want to risk damaging the arbour and I don’t have specialized tools to do the job. I may have to live with it. However, it may not be so bad once the other bushing work is completed.
Gathering pallet pins
Two, I could not remove the centre cam despite pulling and gently prying.
Centre shaft cam
Again, I did not want to risk damaging the arbour. Specialized tools, such as a puller in this case, are required to remove it. That, I don’t have.
This clock has a unfortunate reputation for soft pivots
I will have to work around these two issues. Pressure fitted parts on any movement are very frustrating when said parts cannot be removed without special tools and this one is a challenge indeed. Re–assembly might be a little frustrating particularly with the centre arbour still attached to the rear plate which may effectively be “in the way” of positioning other wheels in place.
I inspected the pivots on the wheels and they all look good (no tapering) with expected wear for a clock of this period. I was worried because this clock has a reputation for soft pivots and perhaps because this is a later model, Sessions might have been introduced harder steel for the pivots. There is plenty of bushing work that needs to be done, however.
On to cleaning, bushing work, re-assembly and testing in Part III.
This is an antique German Junghans time and strike spring driven clock made in the style of a Vienna Regulator. It came to me as a box of parts. To some a box of clock parts and pieces is discouraging but to me it is a challenge.
Part II of a three part series on my newly acquired Junghans Crispi wall clock.
This is Part II of a three part series on my newly acquired Junghans Crispi wall clock. In Part I described the circumstances by which I came across this clock and it’s incredible story as a survivor of the Halifax Explosion of Dec 6, 1917.
This is a German count-wheel strike typically found in the lower lines of Mauthe, HAC and similar clocks. It is an open plate “bread and butter” movement, not of the highest of quality but well built and reliable. The count wheel is located to the rear between the plates and the mainsprings are enclosed in open barrels. There are no helper springs to worry about and all of the wheels are located in the centre and the upper side of the movement.
As you can see in the next two photos the movement was very dirty and I accepted the risk of running it for a day to see what issues might arise. I gave the pivots holes plenty of oil to mitigate any additional wear. What I found was a sticky hammer assembly that would malfunction intermittently which I attributed to dirt and grime buildup, otherwise the movement ran very well after not having run for 100 years. Imagine all that kinetic energy stored in the springs since 1917.
The movement is relatively easy to re-assemble but I had to install the lower centre wheel, the spring barrels and the centre cannon together with the top plate and then slide the gears in between the plates. Fortunately this process is not as difficult as it sounds but very different than laying the top plate right over the gears as you would in an American movement.
Very dirty movement
Mainspring barrel with years of dirt showing
I gave the pivots holes plenty of oil in the testing phase to mitigate any additional wear
Plates cleaned up well
All the wheels between the plates
I found everything within acceptable limits and decided that bushing work was not required
The accumulated grime of 100+ years came off following the ultrasonic cleaning. In fact I have never seen the ultrasonic solution so dirty. The plates cleaned up very well and I gave them an additional polishing with Brasso. After the parts came out of the ultrasonic I tested the movement for any evidence of excessive play and found everything within acceptable limits and decided that bushing work was not required. The pivot holes were pegged and the pivots were polished.
Springs were inspected, cleaned and oiled
There were no cracks or unusual issues with the mainsprings though I found it curious that they were very clean with no rust. There was also very little lubricant remaining. The springs are somewhat tired as you might expect but I think there is enough power remaining for a full cycle so I decided not to replace them at this point. I applied Keystone mainspring oil to the springs once I returned them to their barrels.
With the movement back together, it is time to adjust the strike side. The strike wheels must be set up correctly with respect to each other ensuring that the third (hammer lifting star wheel) and fourth wheels (the strike cam) align with he count wheel. The warning pin on the last wheel (which actually protrudes from the plate) has to be high enough for sufficient rotation. In order to count the strikes properly this relationship must be right. Unfortunately, I can never get this correct the first time.
The servicing of the movement is not without headaches, however.
The servicing of the movement is not without headaches, however. I bent a pivot on the warning wheel which I managed to successfully straighten out. The hammer arbor paddle was barely touching the star wheel and while trying to adjust it, I accidentally snapped it off along with the retaining spring. Although the clock will go though the strike sequence the gong will obviously not sound. I don’t have the tools to put in a new paddle so I will have to get that attended to somehow. I managed to correctly adjust the strike side but the clock mysteriously stops after about an hour or so. Something is definitely amiss and more investigation is required.
I have had more success with the case restoration that you will read about in Part III. In the meantime I have to constantly remind myself that this movement has not been running in 100 years!
Black Forest Clock Company of Toronto, clock in as found condition
Shelf clocks such as the one pictured have always been hard to find though I did stumble upon this one very recently (April 2016) at an antique store in Great Village, Nova Scotia. Why, because of their cheap construction and inexpensive movements, not many of these clocks have survived over the years.
This one might have had a special meaning to someone at one time because it is a memento of the King George VI coronation of 1937 which nicely dates the clock. He became King George VI of England in December 1936 following the death of his father George V and the abdication of his brother. He had been a heavy smoker and in 1951 had his left lung removed then died suddenly in the winter of 1952. Elizabeth became queen later that year.
Black Forest shelf clock after case restoration
Another view of refinished case
This Blackforest shelf clock is only slightly larger than the first Blackforest clock I picked up last summer (2015) and like the other, is time-only.
Company plate on rear of clock
The time-only movement is very simple in design. The pendulum rod, bob and pallets are one piece.
One piece pendulum assembly
To adjust the beat rate you either rotate the bob left for slower rate or right to make the clock run faster or slower. Outside the back plate sits the mainspring which is housed in an open barrel and there are 5 gear wheels plus the escape wheel between two solid plates. This is an identical movement as found in my other Blackforest shelf clock but unlike this clock it was in very poor condition. The movement is German and could have been made by a number of companies at the time; Keinzle, Mauthe, Hermle or Junghans. There are no stamps or markings on this so-called “plate” movement to give any indication of the maker. Typically many Canadian companies such as the Blackforest Clock Company of Toronto (the Forestville Clock Company after the war) imported German movements before the Second World War and installed them in Canadian made cases.
Plate clock movement
Commemorative Edition – 1937 Coronation of King George VI
To refinish the case I cleaned it thoroughly using Murphy’s Soap, applied three coats of dark walnut stain taking care to wipe the stain with a cotton cloth 5-10 minutes after each application. My intent was to fill in the scratches and abrasions rather than radically alter the colour. I then rubbed the cabinet with 0000 steel wool between coats and applied two top coats of clear polyurethane satin finish. I cleaned the numerals but decided against repainting rather preserving the original patina, though I applied Brasso to bring back the finish on the key wind bushing. In the end the case is a little darker but likely closer to its original finish.
Original winding key
I haven’t quite figured this out yet but I think the winding key has a “bottle opener” design to allow the pendulum to be locked during travel. Ideas?
This clock would make a great addition to a any bedroom. It is small enough for a dresser or even a side table, quiet enough (for a mechanical clock) and is still attractive in design after all these years. Heck, you can even wind the clock in the 6 o’clock position.
It is time to buy the tools I need for clock repair. I already have a number of basic tools to get me started; pliers, letdown chucks, screwdrivers, etc.
However, my first significant tool is an Ollie Baker Mainspring Winder which arrived from the USA today. It is pictured below. The Ollie Baker comes with an assortment of collars for every size of mainspring.
Olie Baker spring winder
The spring winder will enable me to inspect, clean, and re-install barreled or open springs on all the clocks I will be servicing. My first impression is that it is a robust and well-machined tool that will give years of service. Indeed, one of the most important tools for clock repair enthusiasts is the spring-winder.
I also ordered bushing kit #5488 from Perrinstoday which will enable me to have the bushings I need in order to use the Bergeon Bushing Machinethat I will purchase later on this year.
The Bergeon Bushing tool is “Swiss made” and exudes quality. In every clock, due to considerable wear, the plates have to be bushed from time to time. This tool allows the bushing of plates of various sizes. The kit includes driving punches, centering bit, stakes, and reamers. I can bush by hand which some folks do by using appropriate reamers and files but I know that a bushing machine is a must-have. The first photo shows a clock movement that I had professionally bushed. It required 5 bushings in all in addition to cleaning and oiling and it runs very well.
With these tools, I can progress more seriously into this most interesting hobby.
Restoring and repairing antique clocks is a rewarding and sometimes challenging journey, and my latest project has been no exception. I recently acquired a time-and-strike mantel clock from the Enfield Clock Company, a British manufacturer known for its utilitarian designs, especially post-war.
Smiths Enfield time and strike mantel clock
In this article, I will share my experiences as I continue to restore this time-and-strike mantel clock, detailing the steps I’ve taken so far, the challenges I’ve faced, and what I’ve learned along the way.
The Enfield Clock Co. & Association with Smiths
The Enfield Clock Company’s history is as intriguing as the clocks they produced. Established in 1929, Enfield became known for its mass-produced timepieces, manufactured using modern assembly line techniques inspired by American factory systems.
By the early 1930s, Enfield was manufacturing clock movements that were sold wholesale, eventually leading to the formation of the Smiths Enfield brand after the company was sold to Smiths Industries in 1933. The clocks, particularly those produced in the 1950s, reflected the utilitarian, post-war aesthetic of the time.
Initial Observations
When I first examined the clock, I could tell that it had been worked on by someone with a tinkerer’s touch, rather than a skilled clockmaker. Although its striking mechanism sounded great and the clock was visually appealing, I knew it required a thorough service to restore its functionality.
This clock occasionally stopped for no apparent reason and was difficult to keep in beat, prompting me to learn more about clock repair. The movement was relatively simple, with two trains, so I set out to clean and service it. As I worked through the process, I encountered some challenges, including an unhooked mainspring and worn pivot holes, but I made progress nonetheless. Though I had to delay some repairs due to my limited experience, I gained valuable insights into the inner workings of this timepiece and look forward to continuing the restoration.
Two pivot holes on the back plate were a little worn but not enough to cause any issues at this time. However, since I know very little about bushing work at this point I think it wise to put off repairs until I know how to do the work. A bushing machine is on the horizon but limited funds do not permit me to tackle those more in-depth repairs just yet. Anyway, back to the movement.
Movement showing hammer, and pendulum leader and bob
While reassembling the strike side the mainspring unhooked. I am not sure why. I was prepared to disassemble the movement to reattach the mainspring but a little wiggling corrected the problem. Once the parts were cleaned in an ultrasonic cleaner and the parts were dried, the movement was assembled and oiled. There are two adjusting two screws on either side of the verge that determine the correct height between the pallets and the escape wheel. Through trial and error, I was able to get a good pendulum swing and a steady beat.
Tricky clip
I decided not to re-attach the 2 clips just yet since it would not take much to break them. Only after the clock has been running reliably and striking correctly will I reattach the clips.
Two ratchets
Not a good design in my view and I wonder if these clocks were ever meant to be worked on after they left the factory.
In the next article, I will share my experiences as I continue to restore this time-and-strike mantel clock, detailing additional steps I’ve taken so, the challenges I’ve faced with this project, and what I’ve learned along the way.
I am continuing work on my Dugena mantel clock with a Hermle movement. Everything seemed to go well after re-assembly but the strike barrel.
A serious problem or simple fix? The latter, thankfully. Something was definitely amiss since the winding arbor was not engaging on the mainspring. The spring was either broken or had not engaged the winding arbor sleeve.
Mainspring barrel
I had no choice but to open up the barrel but it was not much fun getting the cap off. Some suggestions I received on a clock forum site were to bang the arbor with a steel hammer or a rubber hammer and it would pop neatly into my hand. This did not work. Finally someone suggested that if it was really stubborn to find a piece of hardwood, hold the barrel in a gloved hand and bang it with some amount of force on the hardwood. It worked!
Once I got the thing apart I inspected the spring and arbour for possible damage. I initially thought the spring catch (see photo with black arrow) was broken but a member of NAWCC (National Association of Watch and Clock Collectors) assured me that this was quite normal. I re-positioned the catch onto the spring, tested it and snapped the cap back on.
Strike mainspring barrel on the left
The barrel can be easily slid back into the clock without taking the movement apart. Using the clock key I gave it a few turns, tested the action of the strike side and everything seemed to be working.
Arbor sleeve spring catch
Now for bench testing. I put a make-shift hour hand for the clock to see if it marked the hours properly. Testing for a week or so will reveal any issues and allows for finer adjustments before I install the movement back into its case. Everything looks good at this point.
Mainspring with barrel cap off
The original problem was that the clock was running too fast and no amount of adjusting would slow it down. I am hoping now that after a good cleaning it will run as it should.
Antique and Vintage Mechanical Clocks 
You must be logged in to post a comment.