Comparing the Swiss ETA 2892-A2 and the Replica Chinese Sea-Gull ST 18
ETA is the maker of the ETA 2892-A2, one of the thinnest automatic movements for wristwatches with a height of 2.6mm. It has a central seconds and a date display. A similar movement, the ST-18 from China’s leading watch producer, Sea-Gull and it is just as slender as the ETA 2892-A2.
ETA 2892 is a superior movement composed of 21 jewels that ascertain the wheel’s smooth action and it has a power reserve of about 42 hours. But it’s not perfect. For one, its hand-winding mechanism cannot be used extensively because doing so will damage the bidirectional winding’s reversing wheel. When it is wound, the rotor turns along the crown. To correct this issue, it needs to be thoroughly cleaned and lubricated. Sometimes, replacement of some components may be necessary.
A good thing about this movement is that it is very high quality and it’s easy to manufacture it in a large scale. Many luxury watch makers use this movement and it can be modified and turned into a chronograph. Omega used it as the foundation of its first line of co-axial watch movements and the complement escapement of the ebauche was modified with 3 pallet stones and did not require lubrication.
On the other hand, Asia’s leading movement makers, Sea-Gull, manufactures simple automatics and complicated calibers. Its ST 18 was designed with embellished finishes on the balance cock and bridges, and on the top of the movement you can see a perlage finish. Comparing to the Swiss original finishes, it’s evident that there is minimal depth of machining. It would seem that speed is the topmost priority in the creation of this caliber. Viewing through a loupe, you can see rough edges, slots that have been damaged on the screws and even scratches. It doesn’t have a manufacturer’s mark but you can see the serial number on the mainplate, indicating that it has a special status. Among Swiss movements, only those that have passed the chronometer test of the COSC have such numbers.
Moving on, while the Swiss movement has 21 jewels, the Chinese movement has 23. There’s a jeweled bearing supporting the clone barrel on the bridge and mainplate though experts have yet to decide whether such features have any advantage or not. In any case, the jeweled bearing looks more superior than the ETA movement however it’s important to take note that it is very rare for a barrel bushing to be damaged.
When tested on a timing machine, the results on the Chinese movement weren’t quite impressive. It had a weak amplitude and when completely wound, the movement barely made it to 260 degrees. Meanwhile, the Swiss movement had achieved much better values. A completely wound ETA 2892-A2 reached at least 300 degrees and after hours of running, it fell to 250 degrees.
The ST 18 has low beat error and the seconds deviation is under 10 seconds for 24 hours. In comparison, the ETA’s oscillation didn’t drop significantly.
The ETA 2892-A2 has a slightly weaker winding power but it’s one of the best Swiss movements around. Its finishes are faultless, the wheels and pinions are precisely made, and the edges are smooth and clean. On the dial side, Nivrel’s test movement was prepped for modular additions so you cannot see an hour wheel or date disk. The mainplate’s top does not have any embellishments.
ETA’s extensive experience in making movements is clearly evident in the 2892-A2’s excellent rate results, quality craftsmanship, low beat errors and high amplitudes. In contrast, the ST 18 from Sea-Gull looks coarsely machined if you’re to scrutinize it. You can see obvious scratches and the manual work during assembly may have affected the outcome. There’s hardly any oil in some bearings while others are swimming in oil.
It is worth noting that there’s a marked difference in the prices of the movements. The price for each unit of the ST 18 is $60 if purchased in bulk, while the ETA 2892-A2 has a base price of $165. The ST-18 is also readily available while only certain customers can avail of the ETA 2892-A2 and only for certain quantities.
Production of mechanical movements in China has increased dramatically in the last few years. These watch movements are very suitable for accurate mechanical watches and can be available for the mass market even though they are just clones. The manufacture of replicas of existing calibers that are patent-free is legal and even Swiss movement suppliers have done the same thing to compensate for the ETA’s limited supplies. However, in-house development of movements is bound to pay off because it provides the market with unique alternatives. It can be said that the position of ETA as an industrial movement manufacturer will remain unchallenged due to its high quality movements.