Advice -- 116000 OP Beat error: Need service soon?

[horophile1]

Happy New Year! Been a long time...

Need advice on my RX 116000 OP 36 mm (concentric dial; I have posted pics previously), serial M (2007-2008). Purchased this piece from a TRF Trusted Seller 7/2016, and has been an excellent, very accurate piece thus far!

I recently obtained an inexpensive timegrapher, and I was (for fun) testing my six primary pieces that I rotate. I got to my RX OP, and the rate is just fine (settled to +1 to +2 in horizontal, CH position); this is pretty typical of when it is wound and worn on the wrist (it does typically run slower in vertical and winder position). My concern is the amplitude and beat error. All my other (ETA-based) pieces, albeit far newer ones, have a 280-degree amp. and 0.3 ms beat error. Now the RX: great rate, but amp. of high 240s to about 270 (it fluctuates), and beat error not so great at 1.9 to 2.1 ms (usually hovering at 2.0).

My question is: mechanically, should these be of concern, enough to warrant a service in the near future? Is it a potential problem mechanically if I let it go for a while--could it become serious or worse over time? Practically, as for daily function, no worries, it keeps time beautifully (the Watch Check app I've used the last couple of years consistently logs a cumulative daily average rate from about -1.5 to +2.0, never going out of that range, and many of my logs range from 1 to 3-4 months). In fact, without a timegrapher, this issue never would have even occurred to me. I have no doubt that the amp and beat error might be throwing the isochronism out of range a bit (perhaps accounting for some of the positional error).

Unfortunately, the watch had no papers, so I do not know the actual service history (I have never had it serviced during my 1.5 years of ownership). M-serial makes this watch at least 11 years old; hard to believe that the watch could maintain such accuracy without having been serviced at least once during an 8-9 year period (I believe it has been serviced at least once, or had the crystal changed to aftermarket or old new stock--no LEC on the crystal). Still, perhaps its routine service should be upcoming within a year or two.

Anyway, many thanks in advance for expert input! Looking forward to your help and comments. THX! Cheers!

[mnbookman]

The maximum allowable beat error is 0.8ms for your 3135 movement. Your watch has taken a shock, and this has bent the hairspring at the hanger.

Take it to your local dealer and have them evaluate whether or not to watch needs a service. If it does not need a service, correcting the beat error and regulating their watch shouldn’t be expensive.

Given that you have a fluctuation in amplitude, your watch most likely needs service.

[horophile1]

Originally Posted by mnbookman

The maximum allowable beat error is 0.8ms for your 3135 movement. Your watch has taken a shock, and this has bent the hairspring at the hanger.

Take it to your local dealer and have them evaluate whether or not to watch needs a service. If it does not need a service, correcting the beat error and regulating their watch shouldn’t be expensive.

Given that you have a fluctuation in amplitude, your watch most likely needs service.

Great info! We have two AD's in Louisville, plus two indie watchmakers that I've used in the past. I will try to get some info from one (or two) of these.

[Ashton_Horologist]

It is possible the watch took a knock, or it could be something else. Even if the watch took a knock, the likelyhood of the balance spring bending is slim to none. The movebale stud holder may have become loose and moved its way around. Balance springs generally only bend when ‘watchmakers’ get in there and mess them up.

Beat error is basically where the roller jewel sits between the pallet fork horns. It should sit dead center, and the further around the jewel moves, the further the watch goes out of beat.

Due to the age of the watch, and the lack of servicing over that time, combined with the low and erratic amplitude I would ya the watch is very much due for an overhaul. That will sort out all the issue 👍🏻

[horophile1]

Originally Posted by Ashton_Horologist

It is possible the watch took a knock, or it could be something else. Even if the watch took a knock, the likelyhood of the balance spring bending is slim to none. The movebale stud holder may have become loose and moved its way around. Balance springs generally only bend when ‘watchmakers’ get in there and mess them up.

Beat error is basically where the roller jewel sits between the pallet fork horns. It should sit dead center, and the further around the jewel moves, the further the watch goes out of beat.

Due to the age of the watch, and the lack of servicing over that time, combined with the low and erratic amplitude I would ya the watch is very much due for an overhaul. That will sort out all the issue 👍🏻

Thanks! I am beginning to look at servicing options, at least sometime during the next year or two--I won't say it is too urgent unless the watch really starts to go awry. Again, I do not know exactly the servicing history, if any. The watch is 11 years old, and I have owned it for 1.5 yrs (I have never serviced it). I would be surprised that the watch had never been serviced in 9.5 years, as excellent as the average watch rate has been. Unfortunately, I do not know how long the beat rate has been off; I only timed it on the machine recently, so who knows when during the last 1.5 years it went astray.

[padi56]

Originally Posted by horophile1

Thanks! I am beginning to look at servicing options, at least sometime during the next year or two--I won't say it is too urgent unless the watch really starts to go awry. Again, I do not know exactly the servicing history, if any. The watch is 11 years old, and I have owned it for 1.5 yrs (I have never serviced it). I would be surprised that the watch had never been serviced in 9.5 years, as excellent as the average watch rate has been. Unfortunately, I do not know how long the beat rate has been off; I only timed it on the machine recently, so who knows when during the last 1.5 years it went astray.

Could be your inexpensive timegrapher giving wrong information, was testing done with mainspring at full power reserve..

[214270Explorer]

If it is keeping good time, do not be concerned.

[horophile1]

Originally Posted by padi56

Could be your inexpensive timegrapher giving wrong information, was testing done with mainspring at full power reserve..

Thanks for your reply. Yes, indeed it was done at full wind (I made sure to check before testing it). My 5 other watches I tested all came through with good (higher) amplitude and very low beat error, so my OP was the only one to stand out.

[horophile1]

Originally Posted by 214270Explorer

If it is keeping good time, do not be concerned.

Thanks for your reply.
And that's how I see it for now; it still has the best average rate of any watch that I own, which is good consolation for me.