Sorry, "thems fightin' words!"
😀
Can you please describe what "high quality" means to you? In my experience the 7750 is robust, accurate, and very reliable - to me those are very much attributes of a high quality movement. It is large and thick, but those things contribute to it's robust and reliable nature. It's not necessarily pretty, but decoration levels vary quite substantially depending on who is using it and what configuration it's in. For example the 7750 variants used by Omega are decorated at least as well as the 1120 or 2500 are
By the way, the 7750 isn't as thick as people sometimes make it out to be. It is 7.9 mm, and to throw out a few comparisons, the Omega 9300 is 7.6 mm, so not a lot thinner. The Omega 1040 is 8 mm thick, and the 1045 is 8.2 mm, so the 7750 is hardly the thickest automatic chronograph out there.
Yes, the Zenith El Primero is thinner, but have you serviced one? Let's just say they are not my favourite movement for
many reasons, one of them being that there are about 40 different screws used in that movement, so that is what I would call an inefficient design personally. By comparison, the 7750 uses just 8 different screws for the whole movement.
There is a reason that the 7750 is so ubiquitous, and it's because it's a proven performer. As I have often said, when I have a 7750 on my bench, I know I'm going to have a good day, and that service will generally be smooth. There are few weak spots, and the final result is always quite accurate, with little in the way of intervention required to get there from me, so I don't often have to get into procedures like dynamic poising to get decent positional variation. Just simple adjustments will get you there - it is probably the most accurate movement I see post service on average, and that includes variants of the 7750 that are not chronometer certified.
Interesting perspective on unidirectional winding. I don't agree actually, and although many people use winders, the true measure of efficiency is best taken on the wrist. Having serviced more 7750's than I can count, I can confidently say that it is more than efficient enough to stay wound when people wear the watch, which is what counts (never had anyone complain that one would not stay wound on their wrist). Of all the things that the 7750 is, inefficient at winding is certainly not one of them.
The subject of winding efficiency is far more complex than saying that winding in one direction is less efficient than winding in two directions. Certainly on the surface it would seem logical, but you have to dig deeper to fully understand the variables that make up winding efficiency, and the compromises that are present in both single and dual direction winding designs. Depending on how active you are, unidirectional winding can actually be more efficient than bi-directional winding, since there are inherent losses from the dead angle in bi-directional designs. The dead angle is the angle that the rotor traverses where no winding occurs, because the winding system is changing directions in order to wind from one direction to the other. This is why as people lead more sedentary lifestyles, some makers are choosing unidirectional designs, because they wind more with smaller movements of the wrist.
The 7750 uses a rather large and heavy rotor compared to many others, so for example I perform what is known as a damping test on these and others to determine if the bearing is in a good state. This test involves suspending the rotor on a piece of peg wood, turning it to a position that is 90 degrees from the hanging position, like so:
Then letting it swing freely until it stops:
Depending on the movement, the time that is required for it to swing and be considered good will vary. So for a 2892/1120 in the photos, the time should be at least 45 seconds before it stops swinging and comes to rest. For the 7750, you are looking for 1 minute and 20 seconds, and I have often had them swing for over 2 minutes in this test. This means the rotor is heavy by comparison, contributing to the ability to wind.
In fact the ETA 2892, which winds in both directions, is known to be one that isn't a particularly efficient winder, and many watchmakers I correspond with complain about them coming back for this reason after service. It's simply not an issue with the 7750.
So from my perspective as a watchmaker that has to deal with them often, they are a movement I believe is a top performer in my books.
Cheers, Al
