In need of a Sherpa Graph crown in the range Mark Ib through Mark IIb

[Joe_A]

The thread title is the gist of the matter, but below I will tell the tale that goes with it.

I've been sending my watches for full service to RGM in Mt. Joy, Pa for a number of years now and each time, the watch comes back running like new. Like most watchmakers, but not all, RGM states that the vintage watch is not waterproof. Basically, if the crown turns properly, there is no attempt made to replace any gaskets or gasket material.

There are some watchmakers who do not think the job is complete unless they attempt to waterproof the watch as well and they will go through some pains to replace the gasket on the crown.

Such is the case for Precision Horology, Ashton Tracy, where I have had my Sherpa Graph Mark Ib "Gray and White" for service.

He's pretty much finished the reassembly and testing, but in an effort to replace the gasket in the crown, he tripped over a problem.

The gasket was very hard and rubbing on the side of the watch making it stiff to wind and set. He decided to replace the gasket only to find that the gasket was not directly replaceable. He melted the old hard rubber to remove it only to discover that the stem was embedded into the crown with the rubber.

Here is his explanation:

The crown was very stiff to wind due to the old gasket having gone hard, as old rubber tends to do. I greased the crown tube but it was still stiff. I planned on removing the winding stem to get a closer look at what we could do to address the issue. Upon heating the crown (to remove the loctite on the stem) the gasket pushed forward out of the crown by about 1mm. This is a stock photo I took from the internet.

At this point the stem then just turned inside the crown like it had released the hold. I dug out the old gasket to investigate further and found this:

A closer look at the head of the stem:



We can see that the head that contains the female threads was held in place by the embedded rubber. Once the rubber is gone, then the ratchet-like head just floats inside the crown with no means of attachment, In other words, the gasket is more than a gasket. It is the thing that holds the threaded part centered within the hollow inside crown.

Replacing the crown with a generic crown is a non-starter.

If I were to find an original crown where the rubber is not as hard as a rock, that would be a suitable solution.

Alternatively, Ashton is willing and able to further hollow-out the inside of the crown on a micro-lathe and then reduce the diameter of a generic crown to fit inside the original crown and Loctite it into position. A virtue of this approach is that a generic gasket will then be able to be installed and there will result, some degree of water-proofing or at least dust proofing better than any other 21st century solution.

Well then . . .

I'd rather just replace the crown with an original, if available.

Otherwise, I shall ask Ashton to do his bit of magic on the original crown.

Cheers,

Joe

 

[Joe_A]

Is this one correct?

ENICAR CROSSHATCH Uhr Crown-Winder-Button (NOS) Uhrenteil - SUPERKOMPRESSOR, | eBay

Entdecken Sie ENICAR CROSSHATCH Uhr Crown-Winder-Button (NOS) Uhrenteil - SUPERKOMPRESSOR, in der großen Auswahl bei eBay. Kostenlose Lieferung für viele Artikel!

www.ebay.de

 

[Stephanerunge]

Very interesting, as usual, Joe.

 

[Joe_A]

I ordered the first one in the link above. It ought to be cosmetically correct, but we are not sure about the thread size and pitch.

I ordered a second one that looks even more promising. Between the two, one is likely to do the job.

Enicar Compressor Crosshatched S/S "low" crown 6.2 mm - 3.1 mm high N.O.S | eBay

Find many great new & used options and get the best deals for Enicar Compressor Crosshatched S/S "low" crown 6.2 mm - 3.1 mm high N.O.S at the best online prices at eBay! Free shipping for many products!

www.ebay.com

I'll report back here how things work out.

It was a real surprise to find out that the rubber material for the gasket within the crown is also the material that holds the threaded "nut" n place. I'm told that it is not unusual to find that a crown has been attached with a bit of Loctite and that the crown needs to be heated a bit to loosen the Loctite.

Cheers,

Joe

 

[Joe_A]

Some good progress that should enable job completion soon.

Here are each of two candidate crowns:



As far as I am concerned, the difference is negligible and so Ashton is free to choose the one that requires the least effort to install.

For reference:



It seems that the early Mark Ia crown, sans Saturn, may be slightly smaller in diameter than the later crowns?

But, 0.1 mm is just shy of .004 or four thousandths of an inch.

The original crown is 6.12 mm diameter and about 3.1 mm in overall height.

Stay tuned for the conclusion of the story!

Cheers,

Joe

 

[HorologyBiology]

The main problem crown I have encountered issues with many times are the Ops crowns. I've even received NOS ones where they are crumbling and had to send them back. The same issue as above where it has hardened that bad it just crumbles away which of course makes the crown useless as the threaded stem comes away.

Regarding the waterproofing part it's also something I will not do on a vintage watch. Sure I will replace all the gaskets as standard but I'm not going to put a waterproof stamp on it so some guy then thinks its cool to dive 150m with their 60 year old watch... and then blame me

I agree with you and thinks it's best to replace it now you sourced one (probably cheaper as well)
I wouldn't worry too much about the tap size (thread) as a stem extender with different male and female sizes can be used very easily.

 

[Joe_A]

Aston mentioned that he too was unconcerned about the thread size and pitch. The two crowns are different one from the other in regard to tap and my instruction to him is to use the one that is most convenient as they are pretty close to identical in appearance..

I agree that it would be a foolish thing to do to go swimming with any vintage watch.

But . . .

It would be nice if the risk of condensation can be reduced.

The steel used for Sherpa Graph hands is not stainless and the hands can rust quite easily even with one instance of condensation within the watch.

It happened to me a week after a hand-swap so I have first hand experience.

cheers,

Joe

 

[HorologyBiology]

Condensation could also come from a hairline crystal issue.
I've just never personally had an issue with condensation on a watch. A new crystal and gaskets correctly fitted should be enough.
Shame you had that after literally a week! that's extreme.

 

[Joe_A]

Condensation could also come from a hairline crystal issue.
I've just never personally had an issue with condensation on a watch. A new crystal and gaskets correctly fitted should be enough.
Shame you had that after literally a week! that's extreme.

I was having a house rebuilt and it was a hot and humid day outside.

Inside, the contractors had the AC running cold enough to keep milk from going sour. I stepped inside for a bit and then, after I went back outside I happened to look at my watch and it was completely fogged up. It was then that I realized that just one such exposure is enough to start to rust the hands of a watch where common steel had been used inside.

This is what the watch looked like years ago when I bought it from Ancienne in Barcelona:



The hands must have been badly rusted at one time and painted white to hide the damage. Note that the dial was in great shape as were the subdial hands which may or may not have been replaced at one time. A little closer . . .



I used to think that it could take years for such rust to form. Little did I know just how easy it is to see rust on the hands of a watch while the dial and the rest of the watch remains clean.

The before and after photos after just one condensation incident:
Note that just a small bit of rust formed and while wet, bled into the luminous material.

This can also happen with a well-sealed watch as even a well-sealed watch can experience condensation, but the opportunity will be somewhat reduced.

 

[HorologyBiology]

Wow that's crazy, and of course sucks!

It obviously got in somewhere hence why I cannot except your last sentence Joe, if was it was true that a well sealed watch would experience moisture build up then it cannot be a well sealed watch.

New original Sherpa Graph crystals are very thick and sometimes a pain to fit because of how tight the fit is. That crystal bezel has to be removed first prior to fitting then refit for an extra snug fit. Probably just the lighting of the pic you posted but it looks like a lot of crystal fluffing between 9-3 where its come away a bit while fitting. Sometimes you have to adjust the crystal a little as they really are that tight. Again, probably just the lighting but I don't see it on your original pre service pic.

Think about it though, there would be endless up on endless people having the issue. I know you'll immediately disagree with a long post which is fine but let's agree to disagree

 

[Joe_A]

Wow that's crazy, and of course sucks!

It obviously got in somewhere hence why I cannot except your last sentence Joe, if was it was true that a well sealed watch would experience moisture build up then it cannot be a well sealed watch.

New original Sherpa Graph crystals are very thick and sometimes a pain to fit because of how tight the fit is. That crystal bezel has to be removed first prior to fitting then refit for an extra snug fit. Probably just the lighting of the pic you posted but it looks like a lot of crystal fluffing between 9-3 where its come away a bit while fitting. Sometimes you have to adjust the crystal a little as they really are that tight. Again, probably just the lighting but I don't see it on your original pre service pic.

Think about it though, there would be endless up on endless people having the issue. I know you'll immediately disagree with a long post which is fine but let's agree to disagree

It's a fact that a well-sealed watch may experience condensation.

How is this possible?

Because, unless the watch is sealed with purposefully selected inert gases within, there is air in the watch and unless one can authoritatively assert that the air is dry, it is always going to have a dew point or point in temperature range or excursion where condensation can occur.

Having said that, sure, when the watch is well sealed, no additional moisture-laden air will get into the watch. One can't have it both ways though. If the watch is well-sealed, then no new moisture can get in, but also, no air which contains some moisture can get out either.

I've had this discussion with a number of respected watchmakers and where there is agreement is that, a well-sealed watch that was assembled in a very dry environment is less likely to experience condensation when compared with a watch that is not well sealed.

I'm guessing that most vintage watches are assembled or reassembled in something other than a humidity controlled clean room environment.

Kudos to the watchmaker who knows that dry air is the only good air when it comes to assembling a sealed system.

In any case, a week after the incident I described above, the conditions were identical and this time I was wearing a Gallet watch with blued hands. This watch too fogged up and it was then that I vowed to be much more careful about going from a very hot and humid environment to a very cool and dry environment and vice versa if I could possibly avoid doing so. No damage was done to the second watch.

I now feel certain that, when we see a watch with a very good case and near pristine dial, but with hands that contain rust, the watch was most likely subjected to condensation at some point in time and possibly multiple times.

The water droplets likely lay on the hands for a time before absorption into the air.

 

[HorologyBiology]

Just make sure the next time you do home improvements get those watches out of there!

 

[Joe_A]

Just make sure the next time you do home improvements get those watches out of there!

Amen to that.

 

[HorologyBiology]

Amen to that.

Although you have given me an idea now for an experiment video for the channel So I owe you one

 

[Joe_A]

As we know, most watchmakers of the last century assembled watches where the case may have come from source A and the dial may have come from from source B and the hands may have come from source C and the movement from source D . . . or some variation on the theme.

I think the hands that Enicar used rusted pretty easily. This is not meant to be a knock on Enicar.

Do watchmakers use stainless or rust-resistant materials today. I don't know, but I'd bet Seiko takes such into consideration.

Avoid Water Damage: When Your Watch Gets Wet or Fogs Up | DIY Watch Club

You get water in your waterproof watch and it fogs up. What to do? Learn how to diagnose water leakage and fix watches with water damage in this detailed guide

diywatch.club

Edit: From the above article:

• The watch crystal fogs up
  This scenario could happen when you exit a mall and a temperature change happens drastically, much like eyeglasses fogging up when exiting a cold room into a hot room, or simply when you wear your watch, as your body heats up the watch. The fog is condensation formed on the underside of the crystal. This indicates that there is moisture trapped inside the watch, probably during assembly, and does not necessarily point to a leakage.

 

[HorologyBiology]

Didn't I say something about agreeing to disagree

 

[Joe_A]

The saga continues . . .

Crown was fitted to my "JC" Mark Ib Gray & White and as the watch was reassembled, it was discovered that the hand-pipe on the red central seconds hand had a hairline crack and this is why the central hand was not reliably resetting to zero.

I do some amateur machining and I have a min-lathe among other machine tools and I have turned down some pretty small cylinders, but nothing nearly microscopic as a hand pipe. I can appreciate the process without having to do it myself.

Turns out that Ashton has the tools and experience to make a new hand-pipe and set it onto the central seconds, so hopefully, I will see the watch returned in the next couple weeks.

Meanwhile, the Mark III with the condensation damaged hands has returned. Better photos in another thread at some point.