ETA Tech Data
Shanghai B GMT Disassembly
Shanghai B GMT Reassembly
Alpha Movement Disassembly
Many thanks to Bayram Orazov! I made an offer on Time Zone. My Alpha watch for free to anyone who was willing to disassemble it, and take pics of each step along the way. I was very curious as to the quality of the movement. Originally, I was going to do this project myself, but just didn't seem to have the motivation. So, when I posted the offer, Bayram accepted. I have to say, he did an absolutely fantastic job! Below is the post he made on Time Zone with his commentary and photos. BTW - I have no idea about the dirt (lol). This watch is one that I never opened :-)
Happy Sunday, everyone!
Goto Part 2 of the project - The Reassembly - by clicking HERE
As these days are generally slow around TZ, I figured some entertainment is in place. If you recall, a while back the ever so generous John Flynn offered a free Alpha watch to anyone who would tinker with it. Well, I was the lucky guy and in the following report I show some disassembly steps, as we peek inside the Alpha Explorer II. I apologize in advance for a not very uniform picture quality. These were Q&Ds taken in the process with little to no prior preparation.
Prior to disassembly, I’ve worn the watch for a few weeks. It was keeping pretty decent time and overall is rather comfy on the wrist. It doesn’t look too bad either. Some of the case finishing could certainly be better, but being a freebie, I have no right to complain.
In terms of functionality, it has a Cyclops date magnifier, a hacking seconds hand, and a second timezone hour indicator hand. The latter can be set independently of the main time, but is of a continuous rotation nature, not jump hour increments. The movement is an automatic, beating at 21,600 bph…not quite Rolex frequency but close ;-)
The dial says that it’s water resistant to 3 ATM…no wonder there are no seals inside!
The watch has a solid Rolex style screw back with some general BS written on it. The shiny screw-down crown is signed in Greek.
All right, let’s take the back off this thing…
The shock proofed balance ...
... and part of the automatic winding system
We can see that the movement is surrounded by a plastic spacer
…which could have been made from a bottle cap ring. Yes, it’s pretty darn flimsy!
Having the back off allows us to take the crown out like so
The bezel can come off too, although it's not necessary to get the movement out (comes outta the back)
The movement with the dial still attached:
Now let’s take the rotor and autowind system bridge off
Here’s what’s under it:
The winding system is bi-directional. The upper copper colored gear meshes directly with a gear under the rotor. It then transmits its motion to either the lower copper gear or the bigger gear to the left. I said “either” because the two copper colored gears can actually transmit motion in only one direction. To see why, take a look at the following two photos (which were not easy to take, btw)
In the above photos you’re looking at the “bottom” of the gears (copper part on the other side). You will note that these have a two-level construction, and the first level (with the small pinion) can slip against the second level, courtesy of the 5 round rubies that can be seen in the slots. As a result, each gear turns as a whole only in one direction which is key to the entire winding system being bi-directional. Depending on which way the rotor turns, it is either the upper or the lower gear that transmits the motion to the ratchet wheel (the big solid gear atop the mainspring barrel, leftmost in the previous movement shot).
Anyhow, let's keep going. Taking the winding system parts out:
Bah! Almost forgot…you gotta take the hands and dial off:
The other side of the dial (don’t worry, they all look not so tidy, it’s not just the Alpha):
Under the dial:
But more on that later. Let’s first finish disassembling the movement part of the movement ... Balance, go home!
Btw, I think the latest Rolex that Jocke took apart had an identical balance wheel ;-) I don’t want to dismantle the balance assembly completely, as I kind of want to wear this watch again. I now want to completely take out the mainspring bridge, so that there is no torque on the gear train at all (albeit the watch ran down prior to disassembly). But lo! What is this dirt here? And no, it’s NOT grease. It’s DIRT! John? ;-)
That dirty wheel actually has some freedom to move around. It meshes with the crown wheel below the bridge, but it doesn’t have a permanent contact with the ratchet wheel. Since this wonder of a movement allows manual winding (do you hear this, Seiko 7s26?), such mechanism is necessary. You may wonder how does it know when to engage with the ratchet wheel and when not to? It’s actually quite simple and is governed by the torque (or lack of it) from the crown wheel (the closest vertical gear in the below photo)
Think about it: when the crown wheel turns clockwise (i.e. you’re winding it by hand) the crown wheel will push the “crazy gear” (can’t think of a better name) to the right, allowing it to engage with the ratchet wheel and wind the mainspring. And when the automatic winding is engaged, the motion of the ratchet wheel will push the “crazy gear” to the left, preventing the rotation of the crown wheel. As a side note, if you’re not familiar with the keyless works, when you turn the crown/stem, the motion does not directly affect the crown wheel itself. Rather, the stem first turns the castle wheel (the cylindrical gear in the above photo) which then meshes with the crown wheel when the system is in the “winding” mode. The mesh is only one way though. Slip is allowed in the other direction. When the system is in the hand setting mode, the copper lever moves the castle wheel inwards thus disengaging the crown wheel from any motions of the stem. Hope this clears up any confusion there may have been.
To continue, after we take the balance assembly out ..
... we can see the pallet fork and its bridge. I’m not going to take the pallet out here, as it’s a real pain in the behind to get it seated in properly in place. After we take out the mainspring bridge, we can take a peek into the gear train arrangement (yup, nice polished edges on that bridge):
Ok, let’s take the going train bridge off:
Above, you can see the center/main wheel in the forefront, a third wheel a little further back, the escape wheel on the left and one more gear in the background out of focus. Here's that gear:
Unlike in the simple manual wind arrangement, mainspring barrel does not drive the center wheel directly. Instead, the mainspring drives that big gear, which meshes with the third wheel. If you look carefully, you’ll see that the big gear has two pinions. Why? The top pinion meshes with the mainspring barrel teeth, but the bottom one does not engage with anything. It doesn’t seem to serve any function. The only explanation I can think of is that two types of mainspring barrels could be used in this movement. One with the teeth on top, and the other with the teeth on the bottom. That way, there’s no need for a new big gear. Oh well ...
Another reason why I showed the above macro is to illustrate the level of finishing on parts. It was taken with an undiffused light (no milk container ;-)) to reveal all the surface irregularities. Plus, it’s a 10x zoom. I admit, I’ve never worked on a Patek (I don’t think I’ve even seen one in person…I need to get out more), but something tells me that finish quality on the gear train could be a tad higher. Of course, what matters most is how the teeth are cut, and there’s no problem here. It’s just the aesthetics…but at this price point, it would be silly to expect anything better. The same comments apply to the finish of the mainplate and bridges. They are actually plated (nickel?), but some irregularities come through. Again, photos taken with undiffused light:
Well, that’s about all I have to say about this side of the movement. So let’s flip it and look at what hides (or hided) under the dial. To repeat, we start with this:
Now take off the top semicircular plate. It’s other side looks like this:
With the top plate off:
As you can see, having a date and a second timezone function adds quite a few of extra gears and levers.
Fabulous screw quality:
Take the other plate off. It looks like this:
And on the other side:
The movement now:
How does this work? Uhm…my recent BSME doesn’t want to help me out on this. Well, okay, what I know is that the spring and lever on the left of this photo is what holds the date ring from spinning on its whim ...
…and the copper colored “thing” closer to the top is what advances the date. The pyramid of gears somehow interacts with the hour wheel (not in place right now) and after the proper amount of rotation will turn the copper thing’s base. Note that the pyramid’s base has only 4 teeth, the rest is smooth. That should take care of “close to midnight” date adjustment…or so I think. Here’s a view from a different angle:
You know that the balance pivots are shock protected ...
Diametrically opposite is this collection of gears:
It must govern the “GMT” hand, but I didn’t thoroughly investigate how that works, sorry about that. After we remove the date ring:
There’s even a hint of finishing ...
…but its only in that area, nowhere else. They probably had a little free time for practice before building those tourbillions ;-)
Well, there are still a few parts left to dismantle. But if you forgive me, I shall leave them in place. As I’ve mentioned, I’d like to wear this watch again. The further I go with disassembly, the higher is the risk of loosing small parts (I’ve already had 3 close calls here). So this is the end of Part I of the series. If I can put it back together, there will be a Part II, with some extra work done on the movement ;-)
What conclusions can I draw from this? I think the most obvious one is that although it’s an inexpensive watch, the movement is nevertheless pretty well constructed. The finish may not be all that stellar, but it works! It has some attractive features that the praised-around-here Seiko does not possess. Sure, the looks of the watch are more than derivative from a well known Rolex model, but what do you buy a cheap mechanical watch for? As a status symbol or to tell time and have fun watching little gears turn (ok, you can’t see gears turn unless you open it up, but I’m sure you can find a model with a see through back)? I like my Seiko which I paid my own cash for, but deep down in me, I may actually enjoy this Alpha more. Go ahead, shoot me ;-)
I hope you had fun reading this or looking at the pictures, or both. My many thanks to John Flynn for the opportunity, and watch out for the second installment.
Cheers! Bayram Orazov