Differences In Vintage Movements

I would suggest not getting down into the weeds too much with respect to movements, everyone has a favorite, but the differences aren't great. A chronometer-grade movement is more desirable to some collectors, but I wouldn't worry too much about that. The overall condition of the watch is much more important. However, I would generally say that the 3-digit caliber movements from Omega's golden age in the 60s and earlier are generally more desirable than the later 4-digit movements, e.g. cal 1010 from the 70s. Of course, this is largely true of the watches from those eras overall.

I agree with Dan. Any of the 30mm calibers tend to be very good (the 26x manual wind series especially so). The automatic chronometer grade caliber series 55x and 56x are also excellent. You really can’t go wrong with most Omega movements from the 1950s and 1960s. That being said, I would generally avoid bumper movements from the 1950s. Not because they aren’t good (they’re actually very good), but parts are becoming more difficult to find for some calibers and not all watchmakers will service them.

Condition being equal, I 'll take a 56x movement (or the 60x) over most others: well made, able to take a beating, availability of spares.

Problem with 50s movements is that they were often run until death with bad or no servicing at all. Quite a few dead center wheels... I think they are very nice however, but beware of the condition. Also less waterproof cases - > more water ingress in this Era.

551 rules in my book



Don’t listen to the others

The condition of a 60-70 year old movement has more an impact on its timekeeping potential than the model. A watchmaker or experienced collectors can help you out weed the good from the bad. By the early 1960's movements from established brands (Longines, Omega, etc.) were so good that they are excellent timekeepers after a good service. For example, I recently serviced a Longines 847, which is a very thin movement from the 1960's. After cleaning, lubrication and a simple adjustment, the performance was exemplary (see table below).

From my experience: I encountered more than a few rough looking / tampered with 55x 56x omega movements that came out real fine in the end. I keep being surprised by those. Almost all rough looking longines movements necessitated costly or unavailable parts, did not came out great. When those are clean they can perform, but I can buy a 55x 56x movement eyes closed. Not the same with the others. YMMV of course, depending of your own stash of parts and specific expertise.

No question that the 55x and 56x are some of the best vintage calibers out there.

Agree. 55x and 56xfor automatic and 28x and 6xx for manual

55X —> No date.
56X —> Date.

gatorcpa

They share about 75% of the parts. The jewel mounts on the balance are the main difference. 56X movements have a press in lower jewel to clear the date ring.

Another demarcation happens at 563 with the introduction of quickset. So this makes for three different base plates. The bridges are swapable.

75X adds in a day of the week wheel. 601 is no date, 61X is date. Many of these parts are also compatible with the 55X/56X.

There are also about 3 different hand heights in the cannon tube stack, depending on case/dial. 55X and 60X often have a really short cannon pinion/hour wheel. 56X have two different heights, which are mid and long. 75X has a super long center wheel stack to clear the day disk. The center wheel is the same. what stacks on it is not.

The wheel trains on 55X/56X are identical.

Rotors have their own subtleties. There were a few tweaks here and there to reduce bridge pivot wear. (Similar tweaks are also found in calendar mechanisms.)

The extra jewels for the most part are in the rotor assemblies.

564/565 are probably the finest mechanical movements ever mass produced. These must have been made in the 10's of millions.

552 and 601 are great if one does not need the extra bling.

There is also an outlier 570 which is a smaller caliber, and the parts do not fit. (I sometimes impulse bid on these when not paying attention.) 47X/50X are other outliers. The difference being the movement height. There was sort of a competition to make the thinnest movement possible.

The smaller 18mm movements based on the 620 two hander dress movements are also pretty good. There is a more rare 630 manual wind with sweep. As well as he ubiquitous 671/681 which have added date functions. These can often be found in 30mm sized cases. The quality on these is just as good.