Omega Seamaster GMT PRO 50th Anniversary (2534.50.00)

This is a story long in the making. The object in question is the Omega Seamaster GMT Pro, 50th Anniversary edition. Here is the screenshot from the Omega official site.

Offical Omega Site

Seamaster brand has a long and exalted history. First Seamaster was made in 1948. It looked nothing like they do now, but it was somwehat waterproof – you could conceivably swim with it. It did not have a divers bezel, it looked more like a dress watch. Here it is:

First Seamaster, 1948 (c) Truefacet

By 1957, the seamaster that looked like a divers watch was made and the rest is, as they say, history. I am personally, interested in the original wavy dial Seamasters. They became popular when James Bond started wearing them in 1995. They came in blue and black, quartz and automatic. The pertinent model was the 2531.80.00. Here it is:

Seamaster 2531.80.00

Notice the notched bezel ring, the HeV at the 50 minute position, the wavy dial and the crown guards. The design proved to be controversial. Some people liked it, some hated it, preferring instead the more austere look of the Submariner.

There were many versions and special editions from 1995 until now. The size increased from 41 to 43mm, the co-axial movement was introduced, the quartz was phased out. The chronograph version was introduced. The GMT version appeared. The Blue version is considered more desirable, which can easily be seen by the sales of different dials – the blue wavy dial costing about twice as much as the black. There is also a white version, a version with yellow accents, etc.

The followers of this blog know that I have played around with the blue GMT and the chronograph versions. They are true franken watches, with the chronograph only keeping the non-original case and bracelet. I have not been too interested in the black Seamasters with sword hands, but I came across an auction for the genuine dial, crystal (three of them), hands and bezels (three genuine and one fake), for a reasonable price and I haggled a bit for them and won the seller over by my charming demeanour. In a few weeks the package came.

The 2535.50.00 genuine parts

I drawered the parts and thought I would work on them at some point in time. I knew I had a correct case for the parts, I have more than enough movements to use (Guangzhou 6460 GMT was the one I originally chose), but there were a few issues with the case – the one that I had, had a non screw-down crown. That is incorrect for this watch. It also had a HeV, which this watch does not have. Also, the crown guards are supposed to look over the crown for the GMT version, which this case had. In due time (a year or two, I think), I replaced the crown for the Clarck’s “genuine” crown (i.e. they sell it as original, but I suspect it is not a genuine part). This is a fairly involved process – the crown on the Seamasters is pressure fit. I’ll show the process later on. I assembled the watch.

The GMT hand gave me lots of grief – I would need to stake it, which I did, but not successfully. I actually did not get the GMT hand with the package. The GMT and the seconds hands are restricted items – Omega does not like selling them. So I initially used a replica hand, which is not at all the correct one.

I trawled around watchmaker supplies sites and found some hands on a U.S. parts site. I ordered three correct hands. But Omega is brilliant in the sense that their genuine hands come with slightly lower diameter, which needs to be staked. I have a budget staking set, but it does not work well enough. I destroyed two of the three hands I ordered (and they are expensive). No matter, I decided to wear the watch as is. I did not really like it and it just occupied my watch box until the delivery of the correct hand. I replaced the hand and tested for water resistance, which worked well enough. I did not like the case back, because it was neither correct for the model, nor correct for the series (it had the words “Planet Ocean” on it). I might survive it, but I disliked it.

I wore the watch to a conference held at the seaside, but when I arrived to my hotel room, I set the the time and wound it, the crown tube came away from the case. I drawered the watch again and decided I would deal with it soon.

A few months later, I resealed the crown with marine epoxy, but then the movement was playing up. When I disassembled the movement completely, I noticed under the microscope that the minute wheel was pushed into the main plate by force at assembly at the factory, making a hole in the main plate, which meant that the plate was destroyed. I replaced the whole movement with a modified Seagull ST2100 (did the GMT modification and replaced the seconds wheel with an H6 height). Put everything into the case, but when I was screwing in the back case, I must have been particularly ham-fisted, and I destroyed the case back (it was just spinning without tightening). I tried case backs of my other defunct Seamasters, but they were all a milimetre or so smaller, so that did not work. I could use another case, but the other cases (except for the one subject of this blog post) did not have a crown guard over the crown, which I did not wish entertain for this watch, at the time. The other GMT, I will not touch. It took too much time to now destroy it for parts. Also, it is almost impossible to order this rep now. No one has them.

Luckily enough, I have bought, as a lark, a watch that looks like a Seamaster, but it is not – without omega logos or dial, for a ridiculously small amount. I figured that I would use the case for another project. However the interior of the mid case was so different that I could not put in the Omega innards. But the caseback did work on this mid-case. It had no logo, nor the Seahorse, but hey, at least it was waterproof again.

I wore the watch for a bit, but I was really bothered by the genuine bezel insert, which was half a millimetre too high, snagging on sleeves and flying off incessantly.

A few months after, I sanded down the bezel insert and glued it in with the transparent UV glue. The bezel also did not turn, but I did not care about that. The date-wheel also started sticking, to a point where I simply could not set the date anymore. This meant that the date was stuck, which prevented the whole gear-train from turning, which meant that the watch stopped completely. I had no way at the time to open the watch, as we were moving house at the time and my workshop was all packed in boxes. I put the watch back in the box and made a mental note that I need to repair it once I get the chance.

Roll to this April. I finally managed to get access to my tools and opened the watch again, replaced the date-wheel, re-set everything and cased the watch back.

But then, when I set the time, the movement stopped working. I sighed, and tore everything apart again. Even when I completely disassembled the movement into parts, there was no apparent reason for the blockage. I replaced the barrel. I changed the balance, I re-seated the wheels, swapped the autowinder, replaced the date spring again. Nothing. I was stumped. Oh well, I had a NOS (new old stock) Tissot ETA 2836 that I could use, leaving the Seagull to play around with at some later date. I replaced the movement again, re-set the dial, hands and so on.

I put the assembled watch on the timegrapher, to see whether I need to regulate it, but no need.

I happily wore the watch for a couple of weeks. All was fine. But then I decided I would take it to the seaside on our yearly vacation. I would sure as hell want to swim with it. I find divers watches that cannot get wet totally pointless. Therefore, I needed to grease the seals and for the hell of it, test the water resistance again, as now the watch is worth a pretty penny, and I do not want to destroy it by exposing to salt water. Genuine dial, hands, genuine swiss ETA – this amounts to many hundreds of Euros.

I tested the watch, and it failed miserably. Several attempts, I managed to blow out the crystal, the case-back was leaking… To add insult o injury, I managed to bork this case back too by screwing it in incorrectly. To add further insult to injury, the crown tube fell out too. Again. Oh well. I took another watch on holidays. During our vacation, I ordered another Seamaster rep case. However, at this time, it is very hard to any 41mm Seamaster cases (and the is GMT nearly impossible – the only way would be to find someone selling a replica). The new Seamasters are 43mm in diameter. I managed to find a case that is reportedly a 41, however the HeV in that case is conical, as is the case with the new ones. I have not yet gotten the new case, but I suspect that it is misreported as a 41mm. This is a rep case, you understand. The genuine cases are restricted and the midcase alone costs about a 1000 EUR even if you can get them, which is exceedingly hard. A few years ago, I found one of a watch parts site, but they wanted 1750 EUR for it, which is about 2/3 of the price of the whole genuine Seamaster automatic. I decided I would use a regular rep Seamaster case I had laying around, which would mean that the crown guard would be wrong and it would have the HeV which the genuine does not have. The case-back would also be wrong, but at least it would have a Seahorse on it, with no Planet Ocean lettering. The added problem is that it has a crown which is not fit for purpose (it slips, cannot use it for winding). So, my task is clear.

Remove the crystal and all the plastic or rubber parts from the mid-case. Put the mid-case in boiling water to loosen up the crown tube. Put the tube out with the crown wise. Mix marine epoxy, fill the case, push the tube in, leave it for a day to set.

After a day, we have a case with a tube curing nicely.

Since I needed to remove the crystal, might as well put in the genuine one.

There is silicon grease on it. This will be cleaned, of course, before I case the movement.

Close it down and test it. It passes WR with flying colours. I tested it twice. Left the case pressurized for 20 minutes each time. It is all fine. Case the movement. And put on the bezel and the bracelet.

Note how the original crystal and the bezel insert work in perfect unison.

I only need to set the time and wear it. Right? Right? Well, not really :(. I set the time, and then I set the date. It was set to a day after today. So I put the crown into the 2nd position and started quick-setting the date. Today plus five days, quickset stopped working. OK, I thought, fine, I will set it by moving the hands for 25*24 hours. I will, at some later date uncase the movement again and repair the quickset. Because that is under the dial, and that means I would need to remove the movement from the case, take off the hands and the dial and check. And that takes a while, and I have not planned on doing so much watchmaking today. It took me literally 12 minutes of moving the hands. But I managed in the end. Set the time and started doing something else.

Ten minutes later, I noticed that the seconds hand stopped. F*ck. Now I need to open the case, and remove the dial and hands. Will do that, then. But since I am doing that, and since it seems that something is wrong with the movement and the quick set is only one of the symptoms of a deeper malaise, I will disassemble the movement until I find what is wrong and oil it a bit. No need to clean it, as it is pristine, and has been running for a month or so.

Remove the winding weight.

Remove the auto-winding bridge. The train is exposed.

When I removed the dial, two dial washers fell out. One was probably sloshing around under the dial. So this might have been the reason for the issues. The other probable reason might have been that the dial was set too close to front plate. There was a dial spacer installed, but I still might have pushed the dial too much. You never know. In any case, the movement started back up without issues as soon as I removed the dial and the superfluous washer.

A note to self. The 24h hand sometimes lags for a bit, or does not correctly jump ahead when quick-setting. REMEMBER to turn quickset at least once before seating the 24h hand, as that settles it and then it does not lag. So far, it works perfectly. I set the hands under a microscope. If I don’t, then the 24h hand sometimes ends slightly out of position and that annoys me no end.

The hour hand goes on next.

Then the minute hand.

And the seconds. It does not matter where the seconds hand is, as you set it through hacking anyway.

Screw stuff back in. The auto-winding bridge, oiled and ready.

End up with the watch fully assembled.

The final product. The things that are wrong with it:

  • HeV valve.
  • Wrong crown guard.
  • Crown perhaps sticking out too much, but that is what you get with a non-genuine “genuine” crown.

Things that are right with it:

  • Stunning genuine crystal.
  • bezel and crystal fit perfectly.
  • Insert is a bit faded, but it is genuine, so that is fine.
  • Very good lume.
  • Very accurate timekeeping (around 0s/day).
  • Bezel now turns smoothly.
  • Water resistant.

I am well pleased with it. If I come across a better case, I will use it, but otherwise, I am content with it. This journey took more than four years to complete, but the end result is worth it.

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.