Sometimes we get questions about whether one should stabilize lume in hands of vintage watches, so I thought this eBay listing might be of interest. Apparently, a chunk of lume fell out of the minute hand in the process of taking the photos for the listing.

 

Yeah I've had it happen to during a service, too. It's a bummer. A good stablization (from the back) seems like a good idea to me whenever you put a vintage piece into service.

 

A closely related question . . .

I've been wondering whether there is a clear thin lacquer or varnish that one may safely coat the front of vintage hands with that would help prevent rust developing from condensation.

I realize, doing anything to the front of the hands will be far more controversial than stabilizing the lume from underneath.

If you feel my comment dilutes the intention of your OP question, consider it deleted.

 

I think you would be better off protecting your watch from moisture…

 

In the past I've stabilized hands when I see some obvious issue, like cracks in the lume. But lately I've been a bit more consistent with doing this even on hands that don't appear to have any cracks.

One thing I've noted is that hands that look fine to the naked eye, and that even may look good under a loupe, can show cracks when looked at under the microscope. For example these hands looks perfectly fine, even when viewed through a 10x loupe:



But when under the microscope and lit from behind, the crack was obvious:

 

I agree 100%. When you look at enough of these watches it becomes clear that the lume is quite delicate after 50+ years, even on watches that have been treated very kindly. Unless we stabilize the hands routinely, very little original lume will be left in the future.

 

I’ve heard from some old-timer watchmakers that years ago, they used wax to stabilize lume. Anyone heard of this?

 

No, but I would be curious exactly how they supposedly did this.

 

I would only consider stabilising the hands if there were cracked otherwise leave alone. If you have a search on the tinternet you will come across various articles on what type of binder to use depending on the material of the hands.

 

Of course, that goes without saying . . .

I have personally experienced going from an air conditioned and very cool environment out into a hot humid day out of doors, and suddenly, having had a watch fog up. Afterward, the hands apparently rusted very slightly - barely perceptibly. As a result, a bit of iron oxide stained the luminous material.

I don't see how prevention of such a thing can be accomplished after having experienced the phenomenon twice now with two different vintage watches over the space of some months.

One watch suffered the minor staining. The other watch had blued hands and suffered no ill effect.

 

Great topic for discussion. If a binder can be easily applied to back without risk to the hand itself or to existing lume,, seems like a no-brainer. Dial side binders for lume plots and hands would seem to be a riskier procedure?
Do these binders need to be applied just once or repeated every few years?

 

The binder is the same material that is mixed with lume powder to form the paste used for lume. It will last for a very long time.

Applying this binder to the front of hands or to dial lume can change the appearance of the lume,where applying it to the back does not.

 

Perhaps a service with new seals would do the trick? I have never had this happen to me but I don't live in an extremely topical climate, though we get our fair share of such days in the summer.

 

I do not mean to be high-jacking the thread. Such is always bad form. I think this issue ties into preserving the lume and I have a sincere interest in trying to prevent further damage to the lume material..

The two watches in question had each been recently serviced by a well know watchmaker. The damage on the second watch happened days after getting it back from service.

I was having a home built and the tradesmen inside had the AC cranked way up high on a warm humid day.

Seals will not always be enough.

If there is air in a watch, there also may be non-condensing humidity in the air inside. If the seals are good, this air may be trapped in the watch.

At some point, conditions may occur which will cause condensation to take place.

I am convinced that this phenomenon explains why, in some cases, we see watches with pristine dials and hands that have rusted.

If I hadn't witnessed it myself twice in a two-week period, I too would be skeptical. The two incidents happened in September of 2020.

One watch was a Gallet MC45 "Snow White with a pristine white dial and blued hands. I was shocked to see it completely fogged up and I was in no place where I could open the watch immediately to dry it out. As it turns out, no obvious harm was done.

The second watch is an Enicar Sherpa Graph with luminous tritium in the central seconds and minutes paddle hands. The hands had just been replaced with pristine NOS hands with perfectly uniform creamy lume. After the incident, a bit of iron oxide from each of the paddles lightly stained the hands.

Before and after, about a week apart:


The top photo was taken just after the watch was returned from service and is the best of three photos I have before the lume was damaged by condensation days later. The upper photo is a bit overexposed. The lower image more accurately reflects the color of the orange tips and creamy lume.

Cheers,

Joe

 

Do you have proof of a passed pressure test on both?

 

No, I do not, Archer. I assume this is something I should look into?

 

So did your watchmaker say anything at all about pressure testing the watches after service?

 

The watches I have had serviced are vintage watches from the 1960s and early 1970s and I have assumed that they are no longer water resistant. The answer is "no." I did not ask the watchmaker about pressure testing and it was not discussed.

I'm now guessing that the point you may be about to make is that, even when there are no guaranties offered by a watchmaker, the watch should at least be subjected to pressure and vacuum testing such as done with a Witschi Proofmaster?

https://www.cousinsuk.com/product/witschi-proofmaster-s-pressure-and-vacuum-tester.

I've not looked into this issue before today. Your questions prompted a little simple investigation on my part.

The video discusses various levels and methods of testing - and it was all new to me.

At 13:50, the fellow explains how one can stimulate condensation by warming the watch and dropping room temperature water on the crystal. At 15:00, he shows how even a properly sealed watch can be triggered to exhibit condensation, but it is not "heavy" and goes away quickly.

My question was offered up so that I, and anyone else who does not know any more than I do, can learn something from an experienced person such as yourself.

Thank you for taking up the issue and for helping.

 

Thanks - I guess it's a bit unusual for a watchmaker not to pressure test a watch after servicing, as that is a very standard practice. But I don't know what sort of agreement or relationship you have with your watchmaker, so maybe this is something that has been discussed and decided against previously.

In a previous post you mentioned that seals are not always enough, and the there is humidity in the air that is already inside the watch. Both of those are true, and for the seals not being enough, that is exactly why a pressure test is needed even after replacing the seals, to confirm that the watch has water resistance.

The air that is inside the watch has humidity as all air does, but watchmakers will typically control the humidity in their workspace to minimize the chances of very humid air being present when the watch is cased. Generally as the video you found shows, if there is condensation due to humidity in the air, the amount is small and it dissipates very quickly. It is not typical that humidity from the air inside the watch would be enough to cause the changes in the Enicar you have shown, so my guess there is that some other form of moisture had entered the watch at some point.

When it comes to making a vintage watch seal, the success of that will depend on a number of things:

1 - Was the watch ever intended to be water resistant? Many were not so in those instances there's not much to be done.

2 - What is the condition of the surfaces that the various O-rings and seals mate to? If they are damaged or pitted, then replacing the seals may not end up giving you any water resistance. So this means that areas like the case back and the case, where the O-ring goes, must not be pitted, like this:



And also, the case tube where the seal inside the crown rides, must not be worn, like this:



Or this:



Or this:



In all the cases shown here, they were replaced - this is the last one after replacement for comparison of what the tube should look like:



Most of the water damage I see in watches is from water entering through the crown, so the case tube and crown are probably even more critical than the case back and case groove. If you have a vintage watch, it is not likely going to get fully submerged in water, but it will often be worn while washing hands, and the chances of water exposure at the crown are higher than anywhere else in daily use.

3 - The last thing is the willingness of the watch owner to compromise originality for water resistance. As a watchmaker it doesn't matter to me if the owner chooses to replace the seals or not, but if they don't then the watch has to be kept 100% dry.

On the pressure testing, I watched the video - fair number of errors there but not unexpected with these kinds of videos. The comparison of water and air molecules was......

The dry pressure test is the safest in terms of not exposing the watch to water. His description of how the test works is generally okay, if a bit simplistic. The resolution of the machine is actually much higher than he indicates - it measures in hundredths of a micron, not microns.

If the test fails, he says there's no way to know the location, so you have to use a different type of tester - this isn't true at all. These machines have something called a "leak finder" program that will allow you to basically perform the same tests that a wet tester does. So here is a filed pressure test on a watch:



I can use the leak finder program - this pressurizes the case for an extended period of time, and during that time air will move inside the case and the pressure inside the case will be higher than 1 bar:



The machine will monitor the rate at which the air is entering the case, and will tell me if it's safe to perform a water test or not - in this case it was as you can see:



What I do next is place the case into a glass of water, and I can see where the leak is, and how bad it is:

First one is a large leak at the crown. Second is a slower leak at the HEV, and the third is a much slower leak at the crown. Note that when I do these tests in water, the case will not have the movement installed.

The last tests he mentions are the high pressure wet tests. Lot of misinformation there - first being that only manufacturers have this equipment - it is a required piece of equipment to have a full fledged Omega parts account, and I know the same was true for Rolex (when Rolex actually had parts accounts before they started closing then all) so there are plenty of watchmakers who have this equipment. The second is that it's so expensive - the dry testing machine with compressor was far more than the high pressure wet testing machine was.

The last is that the cases are only tested empty. They are tested with the watch fully assembled, so he's incorrect there that the test is only done with empty cases.

My personal procedure for this is as follows:

1 - Dry test with empty case - passes, then
2 - High pressure wet test with empty case - passes, then
3 - Dry test with fully assembled watch - passes, then
4 - High pressure wet test with fully assembled watch.

You can see photos of this in this thread here:

Pressure testing a "Watchco" SM300 | Omega Forums

Hope this all helps.

Cheers, Al

 

Al,

Thank you. Much appreciated.

When I ask questions or post observations, I'm pleased when a response presents a learning opportunity and this is certainly the case (+ crown and pushers too ) today. I assume that there are people in the community who know a lot more than I do about watches . . . and also that there are at least a few who know less than I do.

Though the Sherpa Graph above uses an EPSA case developed for dive watches, I've no idea whether anyone intended for this particular chronograph to be exposed to pressures in multiples of atmospheric pressure. It's a 1966 watch.

I assume that all of my vintage chronographs should stay away from water, but now that I have been focused on this issue, I will take up the matter with my watchmaker for the first time . . . even though I have been using the same firm for a number of years.

I'm tempted to warm the watch slightly under an incandescent light and then use the room temperature water drop test. Should I dare to do so?

What I did do to the two subject watches is to open them up face down in a warm, dry and clean environment under an incandescent warming lamp for an hour and then close them up in the hopes of doing some good.

Thanks again,

Joe