ANATOMY OF AN $85.00 WATCH:
THE SWATCH AUTOMATIC

by Walt Odets

 

The Swatch Automatic reminded me almost immediately of an episode from the Columbo television series of the early 1970’s, and of a scene that only a watch idiot savant would remember. Peter Falk, playing the habitually disheveled, cigar-smoking police Lieutenant Colombo, went to interview a murder suspect at the Van Cleef & Arpels shop in Beverly Hills. Waiting for his suspect and examining some diamond tiaras in a showcase, Columbo is approached by a haughty saleswoman uncomfortable with his appearance.

"May I help you, sir?" she asked.

"No, I'm waiting for Mr. Miller . . . But come to think of it, do you sell watch straps? I've got a watch here that I've been carrying around for weeks." Pulling a watch from his rumpled coat and handing it to the saleswoman, he continued, "It's a good watch - waterproof and shockproof and all that."

"They begin at $25," she said as Columbo handed her the watch. "Hmm . . . seven jewels."

"Twenty-five dollars?", asked Columbo. "No, I don't want to replace the whole thing, just the strap."

"Yes sir, that’s beginning at $25 for the strap."

Columbo declined.

Had Columbo waited 25 years, he might have had an entire 23-jewel, Swiss automatic for about $25.00 (in early 1970’s dollars). I did exactly that at San Francisco Macy’s a few months ago while buying three pairs of new khakis, only one of which would have almost paid for the watch. If the crocodile strap supplied with the $85 Swatch were real, it alone would probably have cost me at least two of the khakis.

Despite the bargain, I had trouble with the croc strap on the Swatch. I went for a free option: a perforated, clear plastic strap with a semi-translucent, swimming-pool blue plastic buckle in place of the black croc. It's as elegant, in its own casual way, as a real black croc strap. And it feels like it belongs on a watch that I can see the hair on my arm through. The whole effect is, in fact, very hairy. There's hair in the balance wheel, hair in the escape lever, and lots of hair coming out of the holes in the strap. It's very casual in a special sort of way. And I like the watch. Eighty-five dollars is extraordinarily cheap these days for anything that actually works, much less an automatic from Switzerland, if not from Geneva itself. If you doubt that this watch is a bargain, consider this: one usually has to pay thousands for the hairy effect in the form of elaborately chased skeletons from, at the very least, IWC. You couldn't get a steel buckle from IWC for $85.00, much less the gold buckle that goes with the $19,995 skeleton. Let's not even talk Audemars or Patek.


THE CASE

The case is - well, plastic, and you can see through it in any direction you look. It is also a fashionably over-sized 37mm, two piece case, with a snap-on back and rounded bezel integral with the crystal and band (side of the case). Parts count clearly matters when you're trying to retail an $85.00 watch, and I imagine that the engineer who came up with the integrated crystal got an extra beer for lunch. The minute track and Arabics are screened on the inside the of the crystal, with an additional seconds track screened on a brushed metal ring just inside the bezel. The case band in reinforced with a 1.5 mm metal ring, as is the case back flange. Water resistance is provided by a plastic to metal seal, with no O-ring, but with an extremely high-pressure fit. Installation of the back required very high pressure in a case vice, a bit unnerving with a plastic watch. (There was no cracking.) The movement is held in the case by a bayonet (clear) plastic ring.


THE MOVEMENT

The automatic movement is the surprise in the Swatch, if only because it actually works. An ETA 21,600 beat per hour caliber 2842, it sports 23 jewels, characteristic ETA-Eterna double click-wheel bidirectional winding (described more fully below), and a rather light base metal rotor. Peculiarly, the words water resistant are stamped on the movement (rather than on the case, which is the water resistant component). The finish of the movement, of course, is absolutely basic. With the exception of the wheels, pinions, arbors, and jewels, there is not even a hint of polishing on even the most critical parts such as the balance or escape lever. All parts are in the most basic, functional form. The hairspring regulator (shown left) is one of many examples. As illustrated at right with the automatic winding rotor removed, the major components of the movement are: the mainspring barrel (1); transmission wheel (between crown and ratchet wheel on the barrel) (2); twin click wheels for bidirectional automatic winding (3); and the balance (4). The 23 jewel movement uses 17 jewels in the basic movement, with another six for the automatic winding system (5). With a top and bottom jewel each, these are (right to left) the two click wheels and the first (of two) reduction wheels between the click wheels and mainspring barrel. The second reduction wheel bearing (6) is simply a hole in the bridge (and a bottom bearing hole in the plate). This wheel, of course, turns more slowly than the first reduction wheel because of reduction by the first wheel. The second reduction wheel, itself, can be seen at (7).


PERFORMANCE: WHAT PRICE PERFECTION?

Given the construction and finish of this movement, its performance is nearly a miracle. Unadjusted for positions, the movement is never-the-less within 19 seconds a day from its fastest position (dial down) to its slowest (crown left). Beat error is 0.4 milliseconds or less (0.6 is usually considered an upper limit for fine movements). Dial-up amplitude (260 degrees) is at the lower limit of what would be expected in a freshly- serviced movement (270 to 315 degrees, dial up). In disassembling the movement for photography, there appeared to be very little lubrication. Rate and beat adjustments appear to have been done at the factory in the dial-up position (by a non-human timer I would think, given the cost of the watch).

The actual trace (and rough, hollow sound) of the movement on the timing machining reveal something about its construction not revealed by the figures alone. As can be seen on the tape (at right), the trace shows many minute variations in rate (instability) in the jaggedness of the line. The general upward slant of the line reflects the rate of plus 7 seconds (when the line runs off-scale, it resumes at the bottom, as seen in the right hand segment); the distance between the two line pairs (not segments) shows the 0.2 millisecond beat error (each line of the pair represents one of the pallets). On extended measurement, the movement actually averaged a beat error of zero and showed a maximum error of 0.3. A 0.3 millisecond variation in beat (in one position) would not be seen in a good movement and suggests irregularity in the balance swings due to manufacturing tolerances in the escapement (escape wheel, pallets, lever, or balance).

For comparison, the trace on a relatively new IWC Ingeneiur (retailing for 65 times the price of the Swatch) is shown. The fully (vertically) expanded line (+1 second/day) is very smooth (constant rate) and shows only short bursts of a 0.1 millisecond beat error, though there was essentially no beat error on average. This is a nearly flawless trace. On an automatic winder (a Cyclomatic with a 45 degree inclination), this watch shows almost uncanny accuracy, accumulating no visible error over a month. In use, the watch shows a gain of one or two seconds per day. Clearly the Swatch would not be able to approach such performance because of the lack of positional adjustment and irregularity of running. The comparison of these two watches suggests that money can buy perfection, but on a very steep curve of diminishing returns.


THE AUTOMATIC WINDING

ETA rotor and gearBecause the automatic winding system of the Swatch automatic is characteristic of all ETA automatics, and because it has been widely imitated (with slight variations to circumvent patent rights), it is worth describing in more detail. The winding rotor, in this case a base metal piece, carries a drive gear that directly engages the two click wheels. As illustrated at right, the rotor mount uses ball bearings, a now common practice, but a design first developed by Eterna and adopted by ETA. The two click wheels (illustrated left) are responsible for the bidirectional winding, transforming either direction of rotor movement into counter-clockwise winding of the mainspring. Each click wheel is comprised of a pair of wheels, one on top of the other. Each pair is connected by a unidirectional click that lies between the two wheels. These directional clicks are the heart of the bidirectional winding. Both top wheels rotate continuously with the rotor drive. Because of the unidirectional click between each pair of stacked wheels, the lower wheel will rotate only if the upper wheel is moving counterclockwise (for the right click as illustrated left) or clockwise (for the left click). The two lower wheels are always engaged with each other and it is the lower wheel of the left hand click wheel (as illustrated above left) that engages the first of the two reduction wheels that eventually leads to the mainspring barrel.

Winding gear trainWith reference to the illustration of the top plate at right, (5) indicates the click wheels; (7) the first reduction wheel; (6) the second reduction wheel; (3) the mainspring barrel ratchet wheel; (4) the mainspring barrel; (2) the transmission wheel that transfers power to the barrel during hand winding (from the crown gear on the winding stem); (1) the stem; and (8) the sprung button that releases the winding stem push piece to remove the stem from the movement. With corresponding numbers, the parts still attached to the automatic winding bridge (inverted) may be seen in the illustration at left. The three lower jeweled pivots on the click wheels and first reduction wheel are visible here. Automatic winding bridgeNote that there is no disengagement of the automatic winding during hand winding in this movement and that all automatic parts rotate during rotation of the crown, all the way back to the two click wheels. Additionally, on this movement the ratchet (to prevent unwinding of the mainspring) is actually provided on the transmission wheel rather than on the "ratchet" wheel of the barrel (visible to the left of the transmission wheel {2} in the illustration above right).

I have prepared a pair of schematic drawings that clearly illustrate the two paths that automatic winding takes with clockwise and counter-clockwise rotation of the rotor. Please click here to view these schematics and an explanation of the operation.


CONCLUSIONS

The Swatch automatic is not a wonderful piece of craftsmanship, but it is certainly a wonderful piece of engineering. That a functional automatic, mechanical wrist watch can be produced for (an estimated) $22.00 is a product of very sophisticated manufacturing technology. I can't imagine not including it in any collection of mechanical wristwatches. If it doesn't feel fancy enough, you can always dress it up with a gold buckle. But the buckle is going to cost a lot more than the watch - unless, of course, you're happy with a virtual buckle. Come to think of it, the whole Swatch with its machine-made movement, transparent case, one-piece bezel and crystal, and swimming-pool strap feels a lot like a virtual watch. I guess that's what I like about it. Like virtual cats and dogs, it's easy to live with. In fact, it's virtually irresistible.

Swatch with gold buckle


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