Saturday, 29 March 2014
The Swiss Lever escapement has a Breguet Sprung screwed balance with double roller, the hairspring appears to be elenvar to reduce temperature variation and the movement is adjusted for temperature. The serial number dates it to 1936.
The Colonial movement is particularly slim and in its case is only 0.4" / 1cm thick.
A perfect watch to wear with evening dress or military mess dress but equally suitable for day to day wear.
Tuesday, 25 March 2014
It was in a sorry state when it arrived and needed quite a bit of TLC to get it back into good condition including fitting a new mainspring, finding and fitting a replacement setting arbor (the time could not be set), a few adjustments, a lot of cleaning and the removal of a previous repair which is the subject of this post.
The movement has a true English Lever escapement with an over-sprung cut-compensating balance and 13 jewels. From the picture you can see the patented ring that sits between the case and the movement and which hold the dust cover.
After opening it up I found that some serious damage had occurred
Notice the large gear too the right is pinned to its "shaft" which is in fact the mainspring arbor, the winding key is applied to the other end of the small gear wheel which turns the larger gear which winds the spring, this is done so that the watch can be wound anti-clockwise as was normal for the Fusee watches still then in production (just).
To rescue the watch he then had a lot of work to do, probably to avoid a difficult conversation with his customer! And its because of this sort of potential problem that I do not do work on other peoples watches.
After grinding the broken end of the arbour flat but leaving just enough of the square shoulder to locate the gear on the arbor, he drilled into the end of the arbor - a tricky operations as the small hole is over half the diameter of the arbour, tapped it and then screwed the gear to the arbour as shown.
I was very tempted to leave this repair but the attachment was a little precarious and as I had a spare arbor from a scrapped "Ludgate" which would fit, not as common an occurrence as you might think, I replaced the arbour and gear wheel.
Saturday, 22 March 2014
The Waltham production records show that about three and a quarter million 1894 models were made of which about 83 thousand were "Riverside" grades but only 10,063 Riverside Maximus grades were made of all types - and that number will include rejects and movements planned to be made but not.
Of these only 2,801 were recorded as Open Faced 21Jewel movements the rest being Hunters or of different jewel count.
The general design is very close to the larger 1899 & 1908 models which followed and has moved away from the captive winding stem of the 1888 model. It has a Swiss Lever escapement with a Breguet sprung cut compensating balance.
This grade also has a double roller, micro adjuster and steel escape wheel as found in railroad grade watches of the period.
Apart from the escape wheel the train wheels are gold and the top plate jewels are screw set in gold mountings. There are diamond cap jewels on the escape wheel and the Balance.
This example has a rare dial signed by Bailey, Banks, Biddle Co. Philadelphia - a very prestigious jewellery maker and retailer.
The case is by the Illinois Watch Case Company of Elgin and is rolled gold.
More pictures can be found via this page of my web site.
Friday, 21 March 2014
A total of around seventy-five thousand 1899 & 1908 Royal grade movements were made but they are normally pendant set. The production records show that only five production runs totalling 4,000 movements included some open faced lever set variants, what the proportion was is not known, all are 1908 models dating from 1919 or later.
Apart from the lever setting the movement is the same as the 1908 pendant set version.
Tuesday, 18 March 2014
The 1899 and 1908 versions are essentially the same and so can be treated together.
These were one of the highest grades before getting to the Railroad grades and their "civilianised" variants. The damascened nickel movement has 17 Jewels, a Swiss lever escapement with a Breguet Sprung cut compensating balance with micro adjuster and is adjusted for temperature and three positions. The top jewels are screw set in gold mountings and it has a gold centre wheel.
The example shown, which has just been restored, has an unusual 3 piece plain dial and which probably originally had a retailers name applied, (see related posts on watch face construction and on blank dials).
Tuesday, 11 March 2014
|The upper reaches of the river Test |
Shipping: I will only be able to ship watches on Monday, Tuesday, Thursday and either Friday or Saturday, usually alternating week by week.
Order processing and queries: On non-shipping days I will usually be able to answer queries and process orders late in the evening, if not then they will be dealt with first thing the next day. Orders will be processed in the order that they are received.
I am a little suspicious that these were not actually for salesmen but I should have been more suspicious of the American watch with such a case I bought in UK where these cases are very rare and never seen on English watches - at least I don't recall seeing one - not least because English watch case construction does not generally lend itself to the form.
Here are the front and back of the case in question side by side.
If you look at the enlarged version of the picture, by clicking on the image, you can see more clearly see that the front bezel on the right has a very worn pattern on it whereas the one on the left does not. What has almost certainly happened is that someone had a watch with a damaged screw-on back and they found an almost matching front bezel that fitted the back and we suddenly have a more valuable display case.
The main body of the watch has a different pattern on it so it is even possible that the case was constructed from three different cases!
I must try and study the pictures more carefully but it's difficult when you are looking at several hundred in a sitting.
Friday, 7 March 2014
|Geneva Stop Gear. |
Click on an image for a larger version.
|The 12 Rotherham 19J Keyless, 1902.|
Thursday, 6 March 2014
|Waltham 1899-Vanguard 23J|
click on the images for a larger view
Firstly what is isochronism in a watch? In brief it is the ability of a watch to run at the same rate as the mainspring unwinds and that is critical for the accurate running of a watch and is a required "adjustment" in a railroad grade watch. So what has this to do with how long a watch runs?
Most pocket watches are designed to run for 30 hours (some are designed to run for 8 days but I am ignoring those for this discussion), to achieve this the mainspring will have to be of sufficient strength to operate the escapement and to have sufficient length and space in the spring barrel for 30 hours operation.
There is then a major problems to overcome, a mainspring of consistent thickness will provide more power when fully wound than when it is almost run down and although careful design of the escapement can make it less susceptible to varying power input it is unlikely to be completely immune so will run fast when fully wound, slower when partially wound and then faster and less reliably when almost wound down due to a weak (short) balance action.
Historically there have been a number of design features built into a watch to overcome these problems including:
An English Fusee movement
showing the chain drive from the
Fusee (right) with its spiral path for
the chain, to the mainspring
The Fusee chain drive which gave a continuously variable gearing and had a high gear at full wind reducing linearly to a low gear as it ran down. This meant that the torque delivered to the gear train was more consistent. It also reduced the minimum and maximum power delivered by the spring in the same way as...
The Geneva stop gear used by the English and Swiss in the late 19th and early 20th centuries but like the Fusee not adopted by the American industry. This limited the winding of the spring from a pre-tensioned state to four complete turns of the mainspring arbore (not the winding gear). This meant that the mainspring was never at maximum or minimum tension and delivered power in a more linier fashion over a narrower range. But it also limited the run time of a watch, particularly one not in tip-top condition.
Introduction of more jewelling to reduce friction requiring less mainspring power (see below) and more accurate fitting of the components to reduce friction and other inefficiencies.
In later years, as metallurgy and manufacturing processes improved, mainsprings were made of varying thickness through their length to provide more consistent power as they wound down, this technology was not however effective around the turn of the century when the Waltham 1899 & 1908 models were designed.
Highly jewelled variants of a movement can run for long periods because of the low friction enabled by so many jewels and in particular the jewelled spring barrel, this means that a weaker spring than the lower jewelled variant is often used (apart from other reasons the movement may otherwise run too hard and break the impulse jewel). A weaker spring is thinner so can be longer and still fit into the usually optimum outer 33% of the diameter of the barrel before winding. So it runs for longer but time keeping will be affected as it runs down.
Tuesday, 4 March 2014
This is one of a series of posts illustrating the main grades of Waltham size 16 watches, primarily the 1899 & 1908 models. Note that specifications did change over time, the description below being typical.
Over six hundred and seventy thousand 7 jewel Travelers were produced in total, with more being made as special order or with other branding. Almost eight thousand 11 & 15 jewel versions were also made, see also the entry for the Marquis model. The movement normally has 7 Jewels, a Swiss lever escapement with a Breguet sprung cut compensating balance. It is unadjusted and has a single roller.