A few observations:
As far as I am concerned it’s very sad that even with the huge slew of new movements that have been introduced during the 3135’s past two decades of continuous use and refinement, there still aren’t too many challengers to the Rolex triple crown of accuracy, reliability and durability – i.e. its toughness – for example, its ability to withstand the abuse of everyday life that most active people, both men and women, would hurl at it, and still keep on ticking. And not just keep on ticking, but to continue doing so accurately too. The only ones that come to mind are the ETA 2892-2A, the ETA 7750 (including their numerous variations and incarnations) and possibly Omega’s new caliber 8500. But unlike the first two movements, the latter one, notwithstanding the fact that it is their 3rd generation of Dr. George Daniel’s co-axial escapement, doesn’t have the advantage of over 20 years worth of use, abuse and refinement, so it’s still an open question as to its long term reliability. So in my opinion, that leaves only two serious contenders to Rolex’s 3135 throne. Of course I would be remiss not to mention Rolex’s own caliber 2235 for its ability to match the three men’s movements. Which is an astounding achievement given the fact that this is a lady’s movement and a lot smaller in diameter and volume than the aforementioned ones.
Initially I was also going to include the Zenith Caliber 400 in this small selection above, but ultimately decided against it because although it’s virtually on a par with the ETA 7750 in most respects, unfortunately unlike the latter, it is only available in various chronograph options.
I’ll be the first to admit that none of these movements will win any prizes for their aesthetics, or their level of decoration. Plus there are other movements that I have mentioned before that can match these three in terms of accuracy, but I haven’t included them here because they are too fragile to be classified as tough movements, or haven’t been around long enough to prove their long term reliability. A perfect example is the JLC 889. An excellent, accurate and reliable movement when serviced by competent watchmakers, but not known for its ability to withstand abuse Then of course we have a few Seiko and Citizen movements that have an outstanding reputation for their toughness and reliability, but most of them fall short in the accuracy department, and one is fortunate if they are accurate to better than +- 15s per day. As a note of interest that standard was more than acceptable for certified COSC chronometers in the 1960s, but most people today expect better, having been spoilt by the standards of their thermo-compensated, atomic clock adjusted quartz watches. And so the COSC have raised their standards accordingly.
And the winner is…
Of these three movements which one do I like the best? If accuracy is your only criteria, then it doesn’t matter which one you choose as there really is virtually no difference between them in that regard. Sure some individual movements might time out marginally better than others, but overall the differences in time keeping between them is insignificant. All three are capable of exemplary accuracy in all six positions, and do so with a minimum of variation and loss to the balance amplitude. More importantly, they should provide excellent accuracy and reliability under real world conditions too.
As for me, please keep in mind that no movement is perfect and that they all have their strengths and weaknesses. Having said that though there is absolutely no question in my mind, that I prefer the ETA 2892-2A over the other two. Okay, so it’s been around almost half a century and in many ways isn’t as sophisticated as the Rolex – no Breguet hairspring, or Parachrom hairspring material etc – but during its long lifetime in its best available chronometer version, it has proven itself to be an exceptionally accurate, reliable and tough movement. Its two main advantages over the 3135 are that it’s quite a bit thinner, only 3.6mm thick versus 6mm, and has only one major weakness – the inefficiency of its automatic winding system, as I mentioned in my earlier review of it. While good enough for most reasonably active folk, it is not efficient enough for those people, young or old, who lead a sedentary lifestyle.
I wouldn’t have any qualms about someone who preferred either of the other two movements though. At 8mm high the 7750 is the thickest and ugliest of the three. It also has the noisiest rotor of any automatic watch that I have worked on, but one cannot question its accuracy, reliability and toughness.
The 3135 is the youngest, most sophisticated and best looking of these three and it has many admirable strengths. A longer power reserve and instantaneous date change to name a few. As for the weaknesses of the 3135? In my honest opinion there are only two glaring weaknesses. The first is that the oscillating weight pivots on a steel post that is riveted to it and held in place by two jewels. The small circumference of said post, coupled with Rolex’s simple and efficient reversing wheels and gearing ratios, greatly improves the winding efficiency of the automatic unit. This is probably the most efficient automatic winding system available today. But unfortunately its tiny diameter doesn’t give enough support to the weight to stop it from hitting against the movement plates every time the watch is subjected to even light perpendicular blows, let alone strong ones. I think that an upgrade to an oscillating weight pivoting on ball bearing races, like they’ve done in their new chronograph movement caliber 4130, is long overdue in order to eliminate this problem. It would be even better if they used lubrication free zirconium oxide ball bearings like JLC, PP and others that are doing so today, not only for their strength, but also for their efficiency over steel ones.
The other weakness is something that may or may not manifest itself as readily, depending on the circumstances and how often the watch is serviced. This potential problem is easily understood by any watchmaker who has serviced a lot of these movements. The problem is that the 2 setting wheels under the dial, and the two small and thin posts that they pivot on, can be easily damaged if the lubrication runs dry. If the grease on the canon pinion dries up due to age or moisture in the watch case, the teeth on these small thin wheels will break off. The more severe problem is if the lubrication on the posts runs dry, then the first post will be worn away in no time at all, as shown in the photo above.
This is less of a problem on the second post as it is a steel pin that is not riveted into the main plate. So it can be easily replaced if it is worn or damaged. Unfortunately the first post is part of the main plate, and is made of brass just like it. Therefore if this post gets damaged like that, the only way to repair it is by replacing the entire main plate. An expensive proposition at best. It’s worth noting that this was not a problem on Rolex’s older caliber 3035 because the diameter of the post was quite a bit thicker, as was the set wheel itself. Please note that this shouldn’t be a problem for those who take care of their watches and have them serviced at regular intervals – every four to five years as recommended by most factories today. I am 100% in agreement with this recommended service interval.
Whether Rolex is interested in making any more radical upgrades to this movement is anybody’s guess, but my feeling is that by now they probably have a replacement waiting in the wings for it. With the economy being in the shambles that it’s in right now, the timing might not be right just yet. Only time will tell. But hey, if anybody gets an email from Bruno Meir about their new movement be a sport and tell your friends on Time Zone about it.
Final thoughts:
A short note about Rolex’s latest innovations – their Parachrom hairspring and Paraflex shock absorber.
I’m not sure why Rolex went this route instead of going with silicone hairsprings like the Swatch Group, JLC etc. This project is a joint venture between Rolex and them, and with the money that they have invested in it, they obviously have the same right as their partners to use this technology. The only reason that I can proffer for them not going with the silicone hairspring, is that they might be obliged to give up using their Breguet overcoil in it.
As an aside, most people aren’t aware of the many joint ventures that the major Swiss watch companies undertake. From a financial point of view it makes a lot of sense if one compares Intel’s R&D budget (or even a much smaller company like Apple) to Rolex’s, one will understand that it makes a lot of sense to pool limited R&D resources with the Swatch Group and Richemont etc.
Having said that though I commend them most highly for finally coming up with a 100% non-magnetic hairspring material. It’s also worth noting that in most of the balance wheels fitted with the Parachrom hairspring that I have seen, they have elected to use the brass Greiner collet instead of their usual metal one. As I mentioned in my review of the 2235 I have a preference for it because it is also 100% non-magnetic.
As far as their new Paraflex shock absorber is concerned, there’s not much I can say about it without putting it though its paces. And no, I have no intention of dropping a $5,000 watch ten feet onto a concrete floor in order to test its efficacy. Especially one that doesn’t belong to me. I know that Rolex has done these tests, but I haven’t personally witnessed them, or examined the watches afterwards. Only time will tell if both their new hairspring and shock absorber are as good as what they claim to be, but I can vouch for the non-magnetic capabilities of the former. Of course if Rolex send me a sample to test, I’ll be more than happy to do so for free!
Dissecting the Helium Escape Valve:
In the first photo you can see the disassembled helium escape valve placed in order of how it fits together. On the left is the piston with its “O” ring gasket. This moves out (i.e. to the left) if the pressure inside the case exceeds the tension of the spring holding it in place. Next is the body of the valve which screws into the watch case from the outside via the slots on its right. The flat portion on the left where the threads end accommodates a flat gasket. The spring rests inside the body of the valve, and this ensures that it is water resistant even without any pressure being exerted on the piston from the outside. Last is a flat metal washer. This is firmly friction fitted to the right hand side of the piston which is tapered in order to accommodate it. The washer also provides a base for the spring to rest on, thereby pulling the piston firmly to the right with enough pressure to squeeze the gasket thus ensuring the water resistance of the valve.
