Gold train wheels....mechanically advantageous or simply aesthetically pleasing?

[PJQL]

Hi all,

I recently had a discussion with someone about the mechanics of watch escapements, and the subject of gold/rose-gold train wheels came up. I have come across a number of Swiss movements, mainly wrist/trench watch sized with three gold train wheels, and the occasional pocket watch with just a gold centre wheel.
I currently have two inter-war wrist watches with three gold wheels, excluding the escape wheel (although I did once come across a full set!)

So the questions: 1...are gold train wheels a mixture of gold and various alloys, and if so, of what proportions would each comprise?
2...are gold wheel simply plated over their entirety, or just the upper surfaces?
3...do gold wheels have any mechanical advantage over brass or other metals?
4...are they simply an aesthetic addition...or a combination of the latter?

Thank you!

Piers

 

[Bernhard J.]

Hi Piers,

1. Gold wheels are always made of gold alloys, because pure gold would be too soft.
2. Gold wheels are not plated, but massive gold (alloy).
3. and 4. I would think that there is technically no difference aside corrosion resistance. But others may know better. They do look nice though.

Cheers, Bernhard

 

[PJQL]

Hi Piers,

1. Gold wheels are always made of gold alloys, because pure gold would be too soft.
2. Gold wheels are not plated, but massive gold (alloy).
3. and 4. I would think that there is technically no difference aside corrosion resistance. But others may know better. They do look nice though.

Cheers, Bernhard

Thank you Bernhard.

Yes...some other input would probably be helpful
I was under the impression that plating was more common. When you said 'massive', what did you mean?

Thanks, Piers

 

[truenewbie]

Hi Piers,
I'm not an expert and whether gold train has superiority over other metal has long been my question too.
I think Bernhard means the wheel is made in gold in its entirety, a practice commonly found in Swiss higher grade PWs. Whereas Americans' like Elgin or Howard usually only has the side displayed plated.

Best, Z.

 

[musicguy]

Elgin or Howard usually only has the side displayed plated.

I have never heard the one side before.


Rob

 

[truenewbie]

Further, strictly speaking, gold train is less susceptible for weathering which in some case can be acerbated and a direct result of wrongful application of lubricant to the meshing teeth.
Thus, personally, it makes more sense to make escap. wheel in gold, for example a lever which requires oiling. Even with the good intent, the advantage in its resistance to corrosion would also run afoul the strength. So what was the choice of balance for those eminent watchmakers back then, the appearance, functionality or even a skill showoff. It is always an interesting discussion.

 

[gmorse]

Hi Piers,

Most English train wheels were gilt brass, and purely in terms of the mechanics of it, I'd have though that brass being less than half as dense as gold would present less inertia, especially at the escapement end of the train and hence be a more desirable material. The whole train stops and starts on every beat.

Since properly designed tooth profiles should in theory engage with only rolling contact, the frictional properties of the metals used shouldn't be a concern, but as we know, the realities of practical implementations very often contradict the theory! In particular, pinion leaf counts have a significant effect on the degree of undesirable engaging friction, quite apart from the perfection or otherwise of tooth forms.

Regards,

Graham

 

[truenewbie]

Hi Graham,

Yes, in theory the tooth profile should be in shape that avoids any sliding friction. So the strength of gold should thus not be a big concern. Very interesting point to layperson like me. Could you elaborate on the inertia? And if PWs with gold escap. wheel in reality runs inferior to others.

Regards, Z

 

[John Matthews]

the realities of practical implementations very often contradict the theory!

So true!

Do you think that watches worked in a sterilised environment? If you were constructing a watch for 'normal' use, would you consider using a gold train?

Piers - a trench watch with a gold train - doesn't sound right to me given the efforts that were made to design cases to keep the dirt out. Can you provide more information on the watches and state whether the train has been verified as gold?

John

 

[gmorse]

Hi Z,

Could you elaborate on the inertia?

The key to this is that the train doesn't run continuously but starts and stops on each unlocking, impulse and locking. Whilst the effect is negligible at the second wheel, it must be at its maximum at the escape wheel, which is why these are made as light as possible in high grade watches. The size of most watch escapements means that the forces involved are tiny, and I really don't know whether any precise comparisons have ever been made between the two metals in these conditions, only that efforts to reduce inertia are continually being made, including lately the use of non-traditional materials.

Regards,

Graham

 

[Bernhard J.]

Whilst the effect is negligible at the second wheel, it must be at its maximum at the escape wheel, which is why these are made as light as possible in high grade watches.

Well, while I am sure that this is absolutely correct, one might wonder why the Glashütte lever escapement typically comprises an escape wheel and lever made of 0.333 Gold (solid). A. Lange and others presumably may be regarded as higher quality.

Density steel: 7,8 g/cm³, brass: 8,5 g/cm³, .333 gold (yellow): 11,5 g/cm³ . So still a quite significant difference, even if it is "only" .333 gold.

 

[gmorse]

Hi Bernhard,

The fact that they felt it necessary to use a relatively low grade alloy of gold with 66.6% of base metals in the mix, seems to suggest that the density of the metal was a consideration. Perhaps you can confirm whether the watches with gold levers and escapes had 'poised' lever designs?

Regards,

Graham

 

[Chris Radek]

Well, while I am sure that this is absolutely correct, one might wonder why the Glashütte lever escapement typically comprises an escape wheel and lever made of 0.333 Gold (solid).

Wonderful! Do you have photos of one? I don't think I've seen this.

Many design choices aren't purely utilitarian - the answer to "why" can simply be "because it's awesome! Just look at it!"

 

[Bernhard J.]

Hi Graham,

The Glashütte lever is indeed exactly poised, although one would not think so just looking at it.

The material is hammered gold, which is said to have the same hardness like steel. Further advantages are said to be that oil does not deteriate so fast like on steel. Finally the gold alloy is non-magnetic, in contrast to steel. But at least the second and third advantages are just as well achieved using brass.

Best regards, Bernhard

 

[Bernhard J.]

Wonderful! Do you have photos of one? I don't think I've seen this.

Hi Chris,

Here is a photo of one of my watches. It is not really spectacular and for explaining the details one would need to take apart the watch. The link provided additionally shows all details of a dismantled Glashütte lever escapement (only as a link for avoiding copyright issues). Believe it or not, the lever is indeed poised. The escape wheel looks just like any other escape wheel aside the gold color.

Redirect Notice

www.google.com

 

[Dr. Jon]

I have read that the Glasshutte escape wheels are aluminum bronze s are the levers. This is light, hard alloy.

 

[Incroyable]

Interestingly the current Charles Frodsham uses hardened pink gold going train wheels for their Double Impulse Chronometer wristwatch.

 

[John Matthews]

I have captured a 1915/16 Dennison cased Waltham wristwatch with a Riverside Maximus movement that has a gold train, but significantly the escape is described as 'steel'.

John

 

[Bernhard J.]

I have read that the Glasshutte escape wheels are aluminum bronze s are the levers. This is light, hard alloy.

This is a copper/aluminium alloy without gold.

Glashütter Ankerhemmung – Watch-Wiki

watch-wiki.org

The relevant sentence translated: "Anchor and escapement wheel were usually made of hammered gold (0.333).". There are exceptions thereof, but rather few.

Best regards, Bernhard

P.S.: The same statement here: Mikrolisk - The horological trade mark index

 

[PJQL]

So true!

Do you think that watches worked in a sterilised environment? If you were constructing a watch for 'normal' use, would you consider using a gold train?

Piers - a trench watch with a gold train - doesn't sound right to me given the efforts that were made to design cases to keep the dirt out. Can you provide more information on the watches and state whether the train has been verified as gold?

John

Hi John,
This is one of the watches I have. It's not an actual bona fide trench watch but a similar sized inter-war piece....probably Fontainmelon?
Regards,
Piers

 

[Bernhard J.]

Hi Piers,

How do you know that the wheels are of (solid) gold alloy, and not guilded brass? Not really easy to clearly distinguish both by amateur analytical means like the acid test. The simplest and most reliable method would be to determine the specific weight using the "gold-water-test". But needs to ensure absence of bubbles when immersing the component under examination, so use a tenside in the water. And a very precise scale, of course.

Best regards, Bernhard

 

[eric the bully]

""In 1902, Gondolo & Labouriau commissioned a Patek Philippe pocket watch with exclusive technical specifications - in this case, a gold gear train - giving rise to the famous Chronometro Gondolo family of pocket watches""

The Gondolo gang

From Geneva to Rio and back, the revival of the Patek Philippe Gondolo watch has reawakened a sleeping Art Deco beauty.

www.thejewelleryeditor.com

Regards enrico

 

[PJQL]

Hi Piers,

How do you know that the wheels are of (solid) gold alloy, and not guilded brass? Not really easy to clearly distinguish both by amateur analytical means like the acid test. The simplest and most reliable method would be to determine the specific weight using the "gold-water-test". But needs to ensure absence of bubbles when immersing the component under examination, so use a tenside in the water. And a very precise scale, of course.

Best regards, Bernhard

That's the point of my post Bernard, I don't know . Hence my queries as to the possible/probable construction of the wheels.
You're right...they do look nice (imho)
But...are they plated..or a gold/alloy combo?
I guess there's no way to find out without removing them....

Piers

 

[miguel angel cladera]

Capturé un reloj de pulsera Waltham con caja Dennison de 1915/16 con un movimiento Riverside Maximus que tiene un tren de oro, pero significativamente el escape se describe como 'acero'.

John
[/COTIZAR]

 

[miguel angel cladera]

""En 1902, Gondolo & Laboriau encargó un reloj de bolsillo Patek Philippe con especificaciones técnicas exclusivas, en este caso, un tren de engranajes de oro, dando lugar a la famosa familia de relojes de bolsillo Chronometro Gondolo""

The Gondolo gang

From Geneva to Rio and back, the revival of the Patek Philippe Gondolo watch has reawakened a sleeping Art Deco beauty.

www.thejewelleryeditor.com

Saludos enrico
[/COTIZAR]
Creo que PP ya usó el tren de engranajes de oro en sus relojes antes del Gondolo.

 

[Dr. Jon]

"Gold" gear trains are common on US made high end watches including top of the line railroad watches. As I recall the these are gold filled, brass with a an applied layer of gold, heavier than plating but with brass inside.

They look lovely and most of these got a lot more use than the high end Swiss watches and have held up well.

I think these work because a very well made watch needs very little torque to run and gold is strong enough for these.

 

[Dr. Jon]

Here is an example in the 60 Hour Illinois Bunn Special

Illinois 23j, 16s, 60Hr, TYPE II, FACTORY CASED, Bunn Special ca: 1926, s/n 4718542 in a factory Bunn Special, Wadsworth “First Model”, 14K, Green Gol

This is a watch that has been on my bucket list for a long time. Not sure I'd ever see one much less own one. It is an Illinois 23j, 16s, 60Hr, TYPE II, FACTORY CASED, Bunn Special ca: 1926, s/n 4718542 in a factory Bunn Special, Wadsworth "First Model", 14K Green Gold Filled case. The fact...

mb.nawcc.org

The gold gears are mentioned in the fine print.

Note that the movement cost $50 bare and $65 cased. About 100years later they still look lovely.

 

[John Matthews]

So is the conclusion - not always clear of their composition, but they look pleasing to the eye, possibly a marketing advantage, became an anticipated addition to high end watches, they retain their good looks, no disadvantages other than cost.

John

 

[Dr. Jon]

I beleive gold may offer a second order benefit.


Gold surface remain smooth while brass and steel are subject to corrosion. The corrosion effects on teh tooth surfaces add friction because they change the profile.

The real top end gears are those made with Ingold fraise cutting.

 

[John Matthews]

What about dirty oil & a gold train?

John

 

[gmorse]

Hi John,

What about dirty oil & a gold train?

No gold elements of the train should have any oil on them, with the possible exception of the escape teeth; it should only be present on the steel pivots.

Regards,

Graham

 

[Dr. Jon]

Another thing about gold in a gear is that it will tend to absorb an abrasive particle. If it gets there it will imbed. This is why gold parts often wear out the harder prts than mesh with them.

In a gear tooth engagement surface, the particle will be pushed in, and out of the engagement.

This is a surmise but my watches with "gold" gears run very well a old age.

 

[viclip]

Another thing about gold in a gear is that it will tend to absorb an abrasive particle. If it gets there it will imbed. This is why gold parts often wear out the harder prts than mesh with them.

In a gear tooth engagement surface, the particle will be pushed in, and out of the engagement.

This is a surmise but my watches with "gold" gears run very well a old age.

Yes this is well known among motorheads. Bushings in which iron or steel engine parts are run, are made specially softer than the within rotating components such as camshafts & crankshafts. The idea is that the iron or steel wear particles sink into the bushing surfaces vs. forming an abrasive slurry which further abrades the cam or crank.

It would be nice if they used a gold alloy in automobile engines but alas the engineers have opted for baser metals ...

 

[gmorse]

Hi Jon,

Another thing about gold in a gear is that it will tend to absorb an abrasive particle.

So will brass, but it appears not to absorb it completely, as illustrated by this English cylinder which runs with a brass escape wheel.



Regards,

Graham

 

[John Matthews]

What about dirty oil & a gold train?

I accept that watches that have gold trains have superior performance. To my mind that is in no small measure due to the fact that all of the components and the construction of the watches were they are used, are superior. Gold trains are only found on top of the range watches.

The advice is not to run a watch unless its service condition is known. This is because of the damage that will occur if dirty oil is allowed to erode pivots and their seating, which if it occurs will adversely impact the performance and wear of the train because of misalignment of the gears and pinions. My thoughts would be that under these circumstances the wear of a gold train would probably be greater than a conventional one. This is the reason for questioning the use of a gold train in a trench watch.

It is probably the case that watches with gold trains are subject to better care and service than the majority of watches, but how would they fair under 'dirty conditions'? - my instinct is that would be subject to greater wear.

John

 

[Dr. Jon]

I suspect that a dirty dusty, environment chews up pivots too fast for much if any wear to occur on gear teeth, regardless of their composition.

I have seem many worn pivots and do not recall ever seeing worn gear teeth.

 

[Bernhard J.]

If a conventional gold alloy .333 is hammered, the mechanical properties are significantly changed, it becomes a lot harder.

 

[PJQL]

I accept that watches that have gold trains have superior performance. To my mind that is in no small measure due to the fact that all of the components and the construction of the watches were they are used, are superior. Gold trains are only found on top of the range watches.

The advice is not to run a watch unless its service condition is known. This is because of the damage that will occur if dirty oil is allowed to erode pivots and their seating, which if it occurs will adversely impact the performance and wear of the train because of misalignment of the gears and pinions. My thoughts would be that under these circumstances the wear of a gold train would probably be greater than a conventional one. This is the reason for questioning the use of a gold train in a trench watch.

It is probably the case that watches with gold trains are subject to better care and service than the majority of watches, but how would they fair under 'dirty conditions'? - my instinct is that would be subject to greater wear.

John

John,

I understand the points that you make about high quality watches. But, the movement I posted here is actually a pre WW1 wrist watch Fontainemelon movement. It's not a higher grade piece, and I wonder why the gear train was ever produced in this manner. It surely must be purely for aesthetics, and the mechanical advantages, if any, are simply an added bonus.
Bearing in mind all the input here, it is interesting to ponder the reasons why gold/alloy trains or plated trains were even bothered with on lower spec' movements unless only for "the look".

Regards, Piers

 

[gmorse]

Hi Piers,

Bearing in mind all the input here, it is interesting to ponder the reasons why gold/alloy trains or plated trains were even bothered with on lower spec' movements unless only for "the look".

Historically, English watches, (and those from most other countries, apart from the very early steel German pieces), used brass wheels and plates which were gilt. Mercury gilding produced quite a thick layer of gold which remains robust even after 300 years or so, resisting wear and corrosion to a remarkable extent. I believe that the wheels in many watches described as having 'gold trains' are in fact plated and not solid, although there are clearly distinguished exceptions to this.

Regards,

Graham

 

[Frank Brower]

Thank you Bernhard.

Yes...some other input would probably be helpful
I was under the impression that plating was more common. When you said 'massive', what did you mean?

Thanks, Piers

I've seen the word "massive" used in reference to a solid or alloyed precious metal to differentiate from plated. A massive is a homogenous mass.

I haven't run across this usage often, and not recently, though.

Frank

 

[Dr. Jon]

From the American watches with "gold" gear trains it is evident the the cost of tehse was not high enough for makers with some extras on hand not too use them when making a lower grade. It may be that Fontainemelon had a chance to buy these as surplus or that took them because they would have to wait too long to get the cheaper ones.

 

[Incroyable]

I've seen the word "massive" used in reference to a solid or alloyed precious metal to differentiate from plated. A massive is a homogenous mass.

I haven't run across this usage often, and not recently, though.

Frank

This seems to be a mistranslation from the French term "or massif" which means solid gold.

 

[Incroyable]

I've run across watches with solid gold plates as well.

For example this very unique platinum and solid gold plate half hunter:

Rare Platinum Half Hunter with Gold Movement | Pieces of Time Ltd

A very rare early 20th Century 18 carat gold English freesprung lever movement in a platinum half hunter case. Spotted gold half plate keyless movement both plates hallmarked London 1912. Going barrel. Plain cock with large diamond endstone, compensation balance with freesprung blue steel...

www.antique-watch.com

 

[Bernhard J.]

This seems to be a mistranslation from the French term "or massif" which means solid gold.

And German, sorry for any confusion created. "Massives Gold" means the same as in French.

I thought to avoid "solid" due to the fact that many US watch cases are described as being plated with solid gold.

 

[Frank Brower]

And German, sorry for any confusion created. "Massives Gold" means the same as in French.

I thought to avoid "solid" due to the fact that many US watch cases are described as being plated with solid gold.

"Massive" in English comes from the French, with origins in Latin, and I'd guess the German word shares that origin. Its several meanings include "very large", or in the sense it's used here, a solid material, not plated or coated (though possibly alloyed).

 

[Bernhard J.]

Additionally, if in German a wheel were described as a "gold wheel", this would be considered as a misrepresentation if the wheel is just gold plated "only".

By the way, a few years ago the EU planed a directive according to which (solid) 8K and 9K gold alloy would not longer be allowed to be called "gold", but "gold containing" only. I however do not know by heart whether this directive came into effect or not. But in Switzerland it is since quite a time by law not allowed to call 8K gold alloy "gold", but only "golf containing material" or "imitate". Thus, in Switzerland it would be a misrepresentation to say that the Glashütte escapement (escape wheel and lever) is made of gold (it is solid hammered 8K alloy). It would have to say that it is made of gold containing material (or even worst, gold imitate).

 

[PJQL]

Thanks to everyone for your input on this subject...much appreciated and much learnt.

Regards and a Merry Christmas to one and all.

Piers

 

[novicetimekeeper]

The material is hammered gold, which is said to have the same hardness like steel

Pretty sure Gold does not work harden, so this is the copper and other metals in the alloy that causes the work hardening. Not sure it will equate to steel. Copper is 3, brass is 4, and steel is 6.5 on the Mohs scale.

 

[Bernhard J.]

The hardening properties of alloys cannot necessarily be derived from those of the pure components. At least this (hardness of steel) was claimed by the Glashütte makers. Which may or may not be somewhat optimistic

Here is a translated description: "But what are the characteristics of the Glashütte anchor escapement? There is the material. The escape wheel and anchor are made of a hammered gold alloy, which, due to its treatment, has about the strength of steel and above all (this was an important argument) does not oxidize and on which the oil stays "fresh" for a long time. ... "

And here some data (although not for the gold alloy in question here):

Mild steel has a Vickers Hardness about 175 (maximum).

 

[gmorse]

Hi Nick,

Pretty sure Gold does not work harden, so this is the copper and other metals in the alloy that causes the work hardening. Not sure it will equate to steel.

That's right, pure gold, being extremely ductile, doesn't work-harden, but copper and silver certainly do and they're the most usual alloying elements. I find that 9 carat gold will become quite springy and tough after hammering, very useful when making watch hands.

Since steels can vary widely in their hardness, partly depending on their heat treatment, the Glashütte claim is difficult to refute.

Regards,

Graham