Wednesday, 8 November 2017

A Pocket Watch for use on Nuclear Submarines.

I was a little sceptical about this but the story checks out. The watch is a standard size 16 Waltham 1908-1609 with 9 jewels, a Swiss lever escapement and a Breguet sprung cut compensated balance with double roller. It is adjusted for temperature and in three positions. The serial number dates it to 1942.


As confirmed by the catalogue number it was originally supplied to the Royal Navy during WWII with luminous hands and face, it was retained at the end of the war, unlike around two million pounds worth of surplus watches and clocks that were sold off.

Later, following the introduction of Nuclear submarines in 1960, it was given non-luminous hands and dial so that the relatively high radiation levels (by todays standards) would not confuse on-board radiation detection equipment. The case was then stamped "Non-Lum".
The American screw backed case is in base metal case and was made by the Star Watch Case Company, it is stamped with the military catalogue number, the Military property mark, the service allocated serial number and "Non-Lum" as described above.

Monday, 4 September 2017

The last version of the Bank watch by J.W. Benson.



The "Bank" Watch was in production a long time, by 1935 a new version was introduced that was almost certainly the last, it is rare and the one pictured is the only one that I have seen.


Although in general layout it is similar to the previous ones this version was much slimmer and had the dial secured with screws rather than pins but amazingly they stick with the slow train movement that most makers had replaced with the fast train 40 years earlier.


I don’t know if it was made in house or bought in but I suspect it was either the former or they used outworkers making to their specification.


One interesting point is that historically the “Bank” watch was cheaper than the Ludgate but this version of the “Bank” was more expensive as explained in this section of a contemporary Benson sales catalogue.

Sunday, 28 May 2017

Dating a Russell Fusee Hunter

11J Hunter signed Thos Russell & Son. Liverpool
There was something odd about this watch when I saw it listed for auction, the case was clearly hallmarked at Chester in 1914 but the movement looked older than that. It is also very unusual to find a "Consular" type case as late as 1914, in fact I don't recall seeing one that late.

When it arrived my suspicions were confirmed as the movement has a very "slow train" running at 15,400 Vibrations Per Hour which was obsolete by the early 1890s. Further research also showed that the trading name on the dial was in use from 1859 though 1894 and the address probably from after the late 1870s.




Case hallmarked in Chester 1914, maker's mark S.Y for Samuel Yeomans.

The case however clearly belonged to the movement they have the same serial number. So the movement had must have had a new case made for it in 1914, a telling point for the provenance of the movement was the makers mark on the case of S.Y, this is for Samuel Yeomans who was mention in my last post but one on a Harrison watch, where there is some background on this important figure in Coventry watchmaking.

The point is that Yeomans was in the business of manufacturing watches, he was not a case maker and it is very unlikely that someone would go to the company for a new case, and the company was unlikely to provide one, unless they had originally made the watch.

So whilst Russell was, I believe, still making watches when this movement was made he is also known to have been buying in watches from Coventry and this is one of them, almost certainly made by Yeomans from a Prescott ebauché (the ebauché makers mark "M.M" is stamped on the movement).

The 11 Jewel Fusee Movement c 1880


This all helps with dating, at first sight from the design etc. the movement is likely to be from c 1850 through to c 1900, the use of a 15,400 VPH slow train narrows this further to a latest date of c1890. The use of a Prescott ebauché probably confirms 1890 as the latest date as by this time Yeomans was also chairman of the Coventry Watch Movement Company who were making Fusee ebauché [3] for the Coventry trade and he was hardly likely to buy in a Prescott ebauché [1]




In 1877 Yeomans [2] was working with Newsome and their movements were marked  "N&Y" as was the Harrison from that date.

So the movement is between c1878 and c 1890 and in my view given the obsolescent very "slow train" most likely from c 1880.


[1] The CWMC did on occasion by in ebauché from The Lancashire Watch Co of Prescott but this is not one of them.
[2] Yeomans first registered is silver mark in 1874, probably for watches made with Newsome - the two together did not have a mark that I can find. It is therefore unlikely that the movement is earlier than 1877.
[3] The CWMC started off making Fusee ebauché  but quickly realised their error and re-tooled for going barrel movements.









Fusee Maintaining Power

One drawback of a Fusee is that power to the movement is lost whilst the watch is being wound, very often this was accepted on Verge Fusee watches but most Lever Fusee watches were equipped with "Maintaining Power" to overcome the problem.


The components fitted to the Fusee cone to provide "Maintaining Power"


To provide maintaining power the Fusee has some additional components, on the right of the picture above we see the underside of the Fusee cone which now does not have the teeth on its edge to engage with the centre wheel pinion.

Instead there are teeth to engage with the two sprung loaded paws on the piece shown in the centre which fits beneath it.

The teeth on the edge of this piece engage with a paw on the movement to prevent it turning the wrong way. The paw is shown in the picture to the right bottom centre, it is swung away from the Fusee in the picture as its spring would push it over without the top plate in position.




The piece on the left has the teeth to engage with the centre wheel and a flat circular spring running in this picture from 3 o'clock around to 12.

The top of the spring has freedom to move about 2 teeth along the rim of the disk, a stud just visible (click on the image for a larger view) engages with the small hole at 12 o'clock on the centre piece, it will be under tension and will provide power to the train during the brief period power comes off with each turn of the key.

The assembly is kept together with a collar pinned to the arbour as shown in the final picture. The slot near the top of the disk is the business end of the maintaining spring. The rivet to the left is securing the other end of the spring.





Tuesday, 23 May 2017

One Watch - Four Names


Fusee Lever signed Harrisson & Son, Darlington. 1877.
The watch has a substantial size 18 Fusee movement in a silver case made in 1877. A nice, well made watch as well it might with 4 well known names associated with it.

 

Long Case Clock by W. Harrison of
Hexham c1825 and insert English
Watch Co Chronograph 1882 signed by
W.E. Harrison of Stockton-On-Tees.
The first and most obvious is that of Harrison (and Son) of Darlington on the dial and movement, the Harrison’s were a large clan of watchmakers from the north east of England, probably related to the John Harrison who won the longitude prise for his 18th century chronometers who originated in Northumberland.
Unfortunately without a great deal of research the actual relationships between the various branches of the family is likely to remain unclear, particularly as many of them were called John or William and several seemed to move around quite frequently.

As best as I can make out from Loomes[i], the Harrison who made our long case clock in the 1820’s and who was at the time based in Hexham (before that he worked in Newcastle upon Tyne and after in Morpeth, then Warkworth and then back to Newcastle) was probably the father or the uncle of the Harrison of Harrison & Son of Darlington.

The second and third names are a bit harder to find, but under the dial the movement is stamped “N & Y”, this is for Isaac J.T. Newsome and (Frederick) Samuel Yeomans, two important men in the Coventry watch trade in the late 19th century.

A Newsome finished CWCCo movement 1894.
Some years after the Fusee watch was made they were trading on their own accounts running two of the larger watch manufacturing operations in Coventry – although small by comparison by Rotherham – making high quality watches.
Unusually both signed at least some of their movements under the dial so they can be identified and they also had their own silver marks so many complete watches are also identifiable.

Early watches were from Prescott ebauché but both were early customers of the Coventry Watch Movement Company and for at least one it is easy to see why......


An unusual watch - made by the Lancashire Watch
Company but resold by Yeomans. 1896.
I have seen considerably more movements by Newsome which suggests that he had the larger business which may be attributable to Yeomans in 1889 being one of the founders and chairman of the Coventry Watch Movement Company. 

Later an S.T. Newsome[ii] was also involved with the CWMCo but it is unclear from my reading in what capacity although he was clearly senior as in 1903 he stood in for the then chairman at the AGM.
The forth big name is the case maker, John Hammon of Clerkenwell.

The Hammons were important makers with addresses in London from 1822 onwards (including a “Manufactory” in Sekforde St) and with what was probably another branch of the family in Coventry from 1869[iii].



[i] Watchmakers and clockmakers of the World, Brian Loomes, NAG Press, 2006.
[ii] Watches 1850 – 1980, M. Cutmore, David & Charles, 1989.
[iii] Watch Case Makers of England, Philip T. Priestly, NAWCC, 1994.

Sunday, 14 May 2017

Verge Fusees and Modern Mainsprings don’t mix.


A Verge Fusee signed by Thos Gilbert of Hythe, 1833.
As explained in some detail my posting “The Fusee Watch” a major problem to overcome in the design and manufacture of clocks and watches powered by a spring is the variation in timekeeping as the spring winds down and power decreases (a lack of Isochronism[1]), typically with high power it will run fast and then slow and perhaps running fast again when the spring is nearly exhausted as a lever movement develops a shallow but fast action.

It is a particular problem with escapements with high friction such as the Verge Escapement invented in the 13th Century and still being used in pocket watches well into the 19th century.
The problem was recognised and addressed by various means over the years, the first successful approach was the Fusee, described in detail my previous post, which provided variable gearing between the spring barrel and the train.
Various other measures contributed to improvements but one of the most significant developments in the late 19th and 20th centuries was the improvements in metallurgy (including a move from steel to alloy construction), design and manufacture of mainsprings which by giving them variable thickness along the length of the spring and other features, allowed them to provide a relatively steady “pull” from shortly after fully wound for at least 24 hours.

Now for the conservator we have a problem. The Fusee compensates for variable power from the mainspring but 20th and 21st century mainsprings are designed for “Going barrel” watches[2] to give reasonably constant power so when the mainspring is replaced the Fusee is over compensating.

The result is that Fusee watches will typically keep time with varying accuracy over time, most particularly those with Verge escapements.

The Verge Fusee:


This is the first proper timekeeping check (a few runs of 1 - 2 hours first got it to this state) on a jewelled Verge Fusee movement by Vale & Rotherham from 1828 with a new mainspring.
 
To mitigate the problem I will, when practical, shorten a much longer spring than would fit in the barrel, by removing the first third or so of the spring the rest will usually be more like an old spring but the best that can realistically be done is to set the regulation so that the watch keep acceptable time for 12 - 18 hours, in the example above setting it to start off running a little fast would see it keep time  within about 90 seconds throughout a working day. So don’t expect too much from a Verge Fusee watch.
 

The Fusee Lever:

On the left a Fusee from a lever movement, note that the grove for the chain
moves in at a steady rate. On the right is the Fusee from a Verge watches. the
grove at the edge of the fuse is moving in at about double the rate of the other
 and the difference between the gearing effect at full and low wind is greater
for Verge , particularly when it is remembered that the run time of the lever
would usually be somewhat longer.
The same problem applies to Fusee lever movements but because of other improvements, the low friction lever escapement and some improvements in mainsprings by the mid to late 19th century the Fusee was far less aggressive and a modern mainspring will therefor have significantly less impact on the lever watch than on the Fusee.


[1] Isochronism : The ability of an escapement to run at an even rate irrespective of the power supplied to it.
[2] In a going barrel movement the barrel containing the mainspring meshes directly to the centre wheel (or sometimes in English movements, notably by the Lancashire Watch Co, through a dummy Fusee – just an extra gear in the train - to give anticlockwise winding) rather than via a Fusee.

Sunday, 7 May 2017

The Fusee Watch.

A problem apparent when clocks were first built using springs rather than weight for power was the variable time keeping as the spring, which was of consistent thickness and temper throughout its working length, ran down. It was particularly severe with the high friction escapements then available.

The solution was the Fusee, a device that altered the gearing between the spring and the train as the spring wound down.
 
A Verge Fusee movement by Vale & Rotherham 1828

The mainspring is in a barrel and connected to the Fusee with a chain (originally a gut cord on clocks) which is wound onto a spiral grove, as the barrel rotates it pulls the chain off of the Fusee giving a continuously changing gear ration and hopefully maintaining a stead pressure on the centre wheel and train.
Top plate of an 1876 11 Jewel Fusee Lever showing the "Fusee Iron"

To prevent excessive pressure on the chain cause by over-winding Fusee stop work (not to be confused with Geneva or Maltese-Cross stop work) is used, this is a lever (The "Fusee Iron" hinged to the top plate which is lifted by the chain as it moves up the Fusee until the lever hits the cam shaped piece on the top of the Fusee (Fusee "Stop-Piece") which prevents further winding. It also prevents the chain overflowing the Fusee and allows some chain to be left on the barrel keeping the chain on a tangent too it reducing strain on the chain hook and keeping pressure consistent at full wind.

One other refinement, known to people Like Harrison when he designed his chronometer was mechanisms for Maintaining Power, a basic Fusee (or weight driven clock) has the disadvantage that when being wound the power delivered to the train is weakened or stopped – not good for timekeeping! – clocks and later Fusee watches have this addition but many Verge Fusee’s do not – perhaps it was assumed that the time would in any case be adjusted after winding so there was not point.
The inside of Fusse Lever movement by J.W. Benson, 1880 on an  ebauché by John
Wycherley of Prescot one of the English pioneers of the "manufacture of  inter-
changeable machine made movements" for which he took out a patent #880 of 1867.

The Fusee "Stop Piece" is clearly visible on the top of the Fusee.
The spring loaded paw at the bottom is part of the mechanism giving
"Maintaining Power" .
By the late 1670’s watches were being made with hairsprings that had a regulator (Tompion’s being favoured in England), a Fusee and a Verge escapement and from the mid 1700s with Cylinder escapements as an alternate. These (and others) all had a considerable degree of friction within the escapement (in addition to turning friction in the train) which required the Fusee.
The Verge Fusse Movement shown above in a later stage of assembly.
The graduated dial is part of the "Tampion" regulator, the centre
arbor drives a rack supporting the curb pins.

In the 1770s a few watches were being made with low friction lever escapements but it was not until the early 1800s with escapements invented and developed by the likes of Massey, Mudge and Savage that they started to become important. The “classic” English Table Rolled Lever escapement appeared c 1823 and then its close relation the Swiss Lever.

These escapements were much better than the Verge etc. in keeping time as the spring ran down but Isochronism [i] was still not achieved without the use of a Fusee and so the Fusee Lever watch was still made in large quantities in England.
During the 19th century various improvements were made which gradually made the Fusee redundant and watches did away with them to be known as “going barrel” watches. Probably the most important change was improved mainsprings that by the 20 century were of alloy, of variable thickness, shape and temper throughout its length to the point that the power produced was essential constant for at least 24 hours.

Other improvements included, reduced friction in the train by improved materials, more accurate manufacture, Jewelling, sometimes on American watches including of the mainspring arbor and for a brief period in the late 19th and early 20th centuries Geneva stop work
The Fusee was not quite dead however, J.W. Benson were still offering a Fusse half-chronometer (The "Rated Watch" and a Fusee Chronometer in the mid to late 1930s.
Benson Catalogue Advert mid to late 1930s.
 

[i] Isochronism: The ability of an escapement to run at an even rate irrespective of the power supplied to it.



Thursday, 4 May 2017

The Lancashire Watch Co / Samuel "Trip Action" movement.

A common LWC full plate movement was known as "The Dummy" referring to a Dummy Fusee wheel / pinion that converted the movement to wind anti-clockwise in the manner of an English Fusee watch. This is the movement commonly found in the popular Graves "English Express Lever".

These movements also have a "Safety Pinion" to protect the workings in the event of a mainspring breaking or suddenly winding down, perhaps due to the click failing.

There is an uncommon variant of this design which I have only seen in watches branded by Harriet Samuel of Manchester. It has a patented device which combines the functionality of both the dummy Fusee and the Safety Pinion. They call it their Patented "Trip Action", it is not clear to me who held the patent, Platt [1] records this variant, also in movements for Samuel, and states that the "Trip" action in the watch is not quite the same as in the patent but similar too it but he does not name the patent holder.


The large dummy Fusee is replaced with a smaller pinion mounted on a swinging arm that is held in place by being pressed against a toothed rack. In normal use this connects the main-spring barrel to the centre wheel pinion. If the spring fails with any force the back-lash causes the pinion to fly away from the centre wheel protecting the train. It can later be reset by pushing it back into position.





[1] Lancashire Watch Company, History and Watches, John G. Platt, Inbeat Publications, 2016 p 281.

Thursday, 27 April 2017

A Bluffers Guide to Watch "Bushing"

Three typical Watch bushes.
Where a steel pivot runs in a brass hole in the movement there will eventually be some enlargement of the hole, often turning it into an oval due to unequal pressure on it.

Occasionally there will be some wear to the pivot as well in which case the pivot will need to be smoothed and reduced in size which will result in it being loose in the hole.

Problems are most common on the fast moving and quite small 4th (Seconds) wheel and on the bottom pivot of the centre wheel which although it moves slowly it has a lot of pressure on it and can't be effectively oiled without taking the movement apart - so it seldom gets done.

To remedy this situation a brass Bush or "Bouchon" is set into the movement.


Part of my collection of Bushes, the two large ones bottom left are for
clocks, those for watches in the top box have an external diameter from
0.8mm to 3mm with a range of hole sizes and depths. These are New
Old Stock, the top set is still available but at £270 the set (120 pieces)
First the original hole has to be opened up to accommodate the size of bush required using progressively larger reamers in the Staking or Jewelling set, this will keep the centre of the hole in the right place.

The bush has to be a friction fit but not so tight that excessive force is required to push it in or the bush could be damaged or the movement distorted.

The reamer on the centre hole of a scrapped bottom plate. The metal is soft and the
tool very sharp so it is just turned by hand with no significant leverage required.
If necessary, which it usually is on the bottom plate, the bush has to be ground down to the same thickness as the plate, on the top plate the shaped end of the bush is left as it looks similar to normal pivot holes and helps with oiling. The bush is then pressed in using the staking set.

My staking set with leaver operation, a different anvil than this would
probably be used when pressing home a bush.

The result will be as efficient as the original.

A re-bushed centre wheel pivot hole that I did recently.

Although more expensive, sometimes a jewel will be used instead of a bush resulting in a higher jewel count than advertised:

This Waltham Traveler has been turned into a 15 jewel watch although I suspect
that was because someone wanted to do it rather than to correct a problem.
On occasion you may find the reverse with a broken jewel replaced with a bush, on the centre wheel this is very unlikely to cause any performance issues - European makers did not like putting jewels on the centre wheel in any case as they add little - except for appearance and marketing - and are susceptible to damage.

Bushes used to replace jewels at the 4th wheel and below will not be as efficient as a jewel and will be more prone to wear in the very long term.

A high grade Keystone Howard Series 5 with the top centre jewel replaced
with a bush. The original jewel was machine set and it was probably thought
that enlarging the hole to replace with a friction fit jewel would have left
the bridge dangerously weak. The brass bush however retains its structural
integrity. There is no noticeable increase in friction and the problem was finding
a mainspring that would not overdrive the movement rather than needing more power.
 

J.W. Benson's Alpha-Numeric Serial Numbers.

J.W. Benson "Bank" watch, 11J, 1922
The case has the same numeric serial number as the movement so the date is pretty certain.
Some Benson "Bank" movements and its derivatives after c 1901 have a serial number prefixed with a letter.  About 12% of the 59 Benson "Bank" watches I have seen have this numbering system but the percentage would be somewhat higher if only watches after 1900 were considered.

Serial number L4381 on the top plate of the 1922 movement shown above.

Some have speculated that this is a date code but I have been unable to find a good correlation.

Things get more confusing if you take off the dial because the serial number prefix on the face plate is always different to that on the top plate.

Serial Number C4381 on the face plate of the 1922 movement shown above.
If the Letter was a date code it would imply that the face plate was made 9 years before the top plate or before the watch was finished which appears unlikely.

Unusually for Benson those movements with an Alphabetic prefix to the serial number often have the same serial number on the case as on the movement but without the prefix which makes the dating certain (unless the watches were re-cased by the maker).

The silver case, hallmarked for J.W. Benson 1922 serial No 4381.

So together with the lack of correlation between the letter and dates it appears the letter represented something else.

But I have no idea what.

The watch from the front.




Wednesday, 26 April 2017

J.W. Benson, 19J, 1904.


J.W. Benson 1904.

This is a very rare, perhaps unique, watch and it perplexes me.


The inside of the Benson 19J movement showing the Geneva stop work
on top of the barrel and the English Lever escapement.

It is a high grade London made size 18 movement with 19 jewels, a Breguet hairspring, gold balance screws and Geneva stop work. And I suspect it is a Half Chronometer (adjusted) movement.
 
But it is branded the "Bank" watch.
 

A Benson "Bank?" from 1904 but with 19 Jewels, a Breguet sprung
cut compensating balance with gold screws and Geneva stop work.

It has the same frame and design as the normal "Bank" watch of the period but I have records for 59 other "Bank" watches in various sizes, in silver and gold and in Hunter and open faced configurations (and I have seen pictures of an awful lot more). None have Geneva stop work and all have 9 or 11 jewels with an over-sprung rather than Breguet sprung balance - which is in accordance with the literature and my Benson catalogue from the 1930s.


A typical Benson "Bank" with 11 jewels from 1920. This is a later version with 4
plate screws rather than the earlier 3 and a slightly different layout of the train.

From the Benson adverts I have seen it was their normal practice to give names to most of their watches, but only the "Bank", "Ludgate" and "Field" had the name inscribed on the movement, others such as their high end "presentation grades" - the "Heirloom", the "Superlative" etc. are simply marked "Best London Make" or similar and with the Benson name, address etc.

The Benson "Superlative" from c 1903, probably an upgraded "Field" and still
in my Catalogue from c1936 then costing 70 Gns as a Gold Hunter or Half
Hunter in it's standard size and £100 as a large (2.5") Hunter.

I can’t understand why Benson would have branded a very high grade watch with the name of what at the time was their entry level London made watch.
 

A "Bank" type watch but with 15J for Sir John Bennett 1893, almost
certainly by P & A Guye.

My best guess is that this was an expensive mistake by the engraving department at  P & A Guye who made a lot of watches for Benson, including almost certainly the "Bank", but who also made variants of the same movement in various grade for Benson and the trade.
 
The earlier version of the "Bank" watch made into the early 20th Century.
Those from the early 1890s had 9 jewels, later increased to 11. The two
plate designs were probably made in parallel for 10 - 12 years. This design
appears to have been unique to the Benson branded "Bank", those sold into
the trade, and some sold by Benson, having the plate design of the later "Bank".