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Title: Seiko 5 Movement Numbers History

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In the early to mid 60s, Seiko seems to have standardized its movement numbers, with the xx06 in a series as the base for the entire series, the 3rd digit representing the grade of movement (so a 6246 is higher than a 6206) and the 4th digit representing the display: 1 = no date, 5 = date only, 6 = DD).

But how true is this for the 62x, 66x, 83x, and 57x? There is surely some relationship among 6206 and other 62xx, but not sure how extensive--for example, the 6201, 6220, and probably the 6222 seem to predate the 6206. Similar case for the 66xx's, which were Sportsmatics. The 6606 and 6619 seem likely to be related, but not sure about the other 66xx: the 6601-05 predate the 06. The 6606 and 6619 are "5"s I believe, while the 6601-05 are not "5"'s as far as I know. There are also some 66xx curiosities like the 6640 "Disney", 6642 and 6659 Schooltime (all 7j), and 6660, about which I know nothing except that it is 21j.

I'm particularly interested in how different movements are related to each other and which evolved from one another, vs. being entirely new designs. Here's what I've figured out so far about Seiko gentlemen's post-WWII watches, followed by a set of questions. Please let me know of any corrections, additional info, etc; and I will post a revision if appropriate.

First of all, as I pointed out in an earlier post, let me observe that Seiko changed its movement numbering system in the early 1960s. The transition seems to have occurred around 1962-63, and I suspect that many of the early 3-digit movements still in use at that time were simply renamed. So I hypothesize the following (names that died out before the transition are not included, ie Crown, Cronos, Fairway). The 76xx that appeared at this time was a Daini line, while the 66xx and 62xx were Suwa.

- 245 = 2451 (Sportsmatic, 1961, Suwa) - 394 = 6205 (Seikomatic Selfdater, 24j, 1962) - 395 = 8325A (Seikomatic Calendar, 39j, 1965?) [Note 395 has no fine adjuster] - [New] 400 not the same as the 6206 Weekdater, contrary to my previous post; the former is 33j and the latter is 26j. The 6206 seems to be a revision of the 400, according to http://www.h4.dion.ne.jp/~smatic/ - 402 = 6220 (Skyliner, Suwa, 1961) - 410 = 6606 (Sportsmatic 5, Suwa, 1963 – first 5) - 430 = 5722 (GS, Suwa, 1963) - 436 = 4361 (Sportsman, Suwa, 1960 - previously cal. 66) - 460 = 6240 (Liner Chronometer, Suwa, 1963) - 560 and 57A = 5700? (Crown, Sowa, 1959) - 603 = possibly the 6201, although the former is 1963 and came in 17, 20, 21, and 30j variants, and the latter is 1960 and 20j, according to the movement table - 620 = 3140 (Liner, Suwa, 1960) - possibly also = 6200?? - [with addition of autowind, became 6201] - 665 Sportsmatic Calendar, 19j, 1962 – appears to have died out at this time - 820 = 7625 (Sportsmatic Cal, 17j, Daini) - 830 = 8301 (Seikomatic Slim, 30j, non-calendar, Suwa) - 840 = 8305B (Seikomatic Slimdate, 30j, 1963, Suwa) [http://www.h4.dion.ne.jp/~smatic/ lists the 840 as the 8305] - 860 = 7622 (Champion, 17j, Daini) - 956 = 6222A/B (Skyliner Calendar, 21j, Suwa) - 957 = 6602 (Sportsman Cal, 17j, Suwa)

Early Beginnings

Their primary watch after the war, and their first with a true -sweep second hand was the Super. This was a Suwa product, which I believe was introduced in 1950 (A Journey in Time lists it as 1940, but I believe that must be a typo). It was gradually refined as Seiko attempted to come up to Swiss standards, and Daini Kameido came out with a similar but thinner design, the Unique. I don't know if these have a movement number and I don't see them in the movement table. The Super also had a calendar version, the AutoDator, with a fourth center-mounted hand and dates around an inner ring.

By the way, apparently in the early years, both Suwa and Daini-Kameido-Tokyo plants were part of the “Daini” portion of the Seiko organization--only later were these referred to as Suwa and Daini.

Early Refinement

The next major design was the Marvel in 1956, which with the addition of an auto-wind capability, was called the Gyro Marvel (movement 290). This watch was produced from 1956-59 by Suwa in 17, 19, and 21j versions.

Daini responded with the Cronos in 1958 (54A caliber), which was thinner, had a bridge anchored at both ends, and the Diashock technique. Suwa responded with the Crown (560 caliber) in 1959. These were supposedly the genesis for the 3180 GS (Suwa) in 1960. The 5720 GS also came out in 1960 at 25j, followed by the 5722 calendar at 35j in 1963. All these were handwind.

The Crown and Cronos went through several versions: - Crown (Suwa): the 57A and B, the 5760 Special and the 341 Special, all in 1961 (I don't know how related these are). - Cronos (Daini): 810 Cronos Special, 1962 I have no idea why so many different Crown versions appeared in 1961--my best guess is that these were different designs sharing a model name to use its established brand value, kind of like Pentiums did. All these were likely (according to my inferences anyway) evolutionary improvements on each other.

During this time, Seiko was also developing a 2nd-tier high-end category, one notch below the GS, the King Seiko. Unlike the GS, which had versions from both Suwa and Daini, the KS seems to have been purely a Daini product for its entire existence (44, 44xx, 45xx, 56xx, 52xx), except for the 56xx’s. The KS started with a mystery caliber in 1961, 25j non-hacking--there seems to be some controversy in the archives about whether this mystery caliber is an early version of the 44A, or whether a wholly different movement. The latter seems more likely given the fact that the first KS was not hacking, and the 44A was not introduced until 1964, whenceforth I believe the KS was always hacking. Thanks to Don C for clearing this up.

In parallel with the ongoing development of the Cronos and the advent of the KS, Daini came out with a short-lived high-end, slim watch called the Goldfeather, caliber 60A, 1960, which had 17-25 jewel versions. The Goldfeather seemed to die out quickly.

Suwa's next "mainline" product was the Liner, which was introduced in 1960 and also went through several generations: 3140 and 620 (1960), 6240 and 460 Liner Chronometers (1963)--these may be different names for the same movement. The 3140 and 620, at least, were likely another evolutionary step in thin dress movements. By the way, I believe none of the preceding watches were hacking. Among those that were automatics, none were hand-wind. The 3140 Liner, according to http://www.h4.dion.ne.jp/~smatic/aboutseikomatic.html was the basis for the 62xx Seikomatic series--in fact, this site claims that the 6201 is basically a Liner with auto-winding capability added, similar to the way the Gyro Marvel evolved from the Marvel. The first Seikomatic was the 6201--the next automatic after the Gyro Marvel. In 1961 the 6601 Sportsmatic was another automatic. Other existing 3-digit movements seem to have been incorporated into the 62x Seikomatic line. More on this later.

The Sportsman also came out of Suwa in 1960: movements 175, 436/4361, and 66, then the 957/6602 calendar (year unknown). This may have been the predecessor to the Sportsmatics, and indeed the 957 became the 6602, and the 66xx series was the “Sportsmatic series”.

An Era of Rapid Innovation and the Ascendancy of Suwa

The 402/6220 Skyliner was introduced by Suwa in 1961, followed by the 956/6222 Skyliner Calendar (non quickset date), apparently in the same year. The Skyliner moved on to the 61A and 6102 in the late 60s, which I suspect were the movement used for the edgier-styled Skyline models.

The 6201 Seikomatic and 6220 Skyliner in 1960 and 1961 seem to be the genesis of the 62xx series. This series has so many notable movements, and 1962 or so seems to be the beginning of a rapid acceleration in the number of different movements and models. By the way, from what I have read and similarity in movements, there has been debate about whether the 35j 6218 was a dry run for the 6245 GS (same jewel count, different fine adjuster type, and different calendar, with the 6218 being D/D and the 6245 date only). It seems more likely that the 39j 6216 was a dry run for the 6246 GS. The 6218, in turn, seems to be an improved version of the 6206, which itself is a revision of the 400. [Source: http://www.h4.dion.ne.jp/~smatic/] Here’s a synopsis of the 62xx series:

- 1960: 6201 Seikomatic (aka 603) - 1961: 6220 Seikomatic (aka 402) - 1962: 6205 Selfdater (aka 394) - 1963: 6206 Weekdater (aka 400) and 6240 Liner (aka 460) - 1964: 6218 Seikomatic and 6217 Silverwave - 1966: 6245 and 6246 GS - 1967: 6215 300m diver - Unknown dates: 957/6222 Skyliner calendar and 395/6216 39j

I believe many if not all 62xx’s were hacking, but none were handwind and among those with a day of week, none offered quickset on the day of the week. The 6222 Skyliner was not even quickset date. By the way, the 6216 and 6218 had both the dolphin and crown logos on the back. Other notes: 6216, 6245, and 6246 have rack & pinion fine adjuster, while the 6218 has the tadpole.

In parallel with the 62xx series, Suwa developed the 66xx series, which boasted the Sportsmatics and was the advent of the famous Seiko “5”. I believe this was thicker than the 62xx’s. The 66xx’s were not hacking, handwind, or quickset as far as I know.

In 1963, the 83xx series was developed, which seems to be a competing series versus the 62xx’s and focused on thinner movements. Some of these may have been reworkings of the 62xx’s--some of these are even called Seikomatic-R, with the “R” possibly being for “reworked” or something like that. The 83xx boasts 8305 (was either the 830 or 840, not sure which) 30j Slimdate, the 8306 30j Business/Weekdater (often bearing a Sealion logo), the 39j 8325, and the 27j 8346.

So in order of thickest to thinnest of these contemporary Suwa series, we have 66xx->62xx->83xx.

Daini seemed to compete tit for tat with Suwa in the late 50s and very early 60s, then seems to have the weaker 76xx series in 1963-64, which included the Champion and what I believe were the first DX models. It then seems to drop off the movement table til the 1967 51xx series, then drops off again til the 70xx series in the early 70s, which is noted for the chronographs with flyback complication that followed the Suwa 6138/39 chronographs. Don C points out that this is probably because Daini had chief responsibility for ladies’ movements, and indeed there is a plethora of 2xxx ladies’ movements in the 60s.

About the Champion: I’m guessing this was a mid-grade movement as compared to the contemporary, high-end Cronos. It evolved through the 850, 851, and 7622/860, all in 1963. One of these models was known as the Flying Fish--don’t know if it had the corresponding logo on the back. Daini also produced a Fairway 760/61 in 1962 (21j in movement table, although SCWF archive shows a discussion of an apparent 17j model—I have to wonder if this is an incorrect dial?), and then the 820/7625 Sportsmatic Calendar in 1964, which seems to be the end of the road for the 76xx series.

Also in the early 1960s, we see the 57xx series from Suwa in parallel with its 62xx and 66xx lines. The 57xx series strikes me as a real hodgepodge. We have the 5720 GS from 1960, 5760 Crown Special from 1961, then 5722 GS’s from 1963, 571x hand-wind chronographs from 1964, and the 5740 Lord Marvel, which came in lo-beat (18k, 5740A/B, 1964) and hi-beat (36k, 5740C, 1967) versions. I don’t know to what extent these 57xx movements are related, if at all.

And in parallel with all this activity in the 1960s, we have the high-end handwind 44xx series, which I think had its genesis in the first-gen KS (a Suwa 44 model I believe), but seems to have entered more serious production 1964-65 under Daini.

The Product Lines Matures, and the Continued Dominance of Suwa

In 1967, it looks like the Seikomatic and Sportsmatic lines die out, and we see the advent of the thinner workhorse 61xx movements, which cover everything from the 6102 Skyliner and 6106 dress watches, to the 6117 Navigator and World Timer watches, to the 6105 diver, to the 6138/39 chronographs, to the 6145 and 6156 GS’s, 6185/86 GS VFAs, and the 6159 300m and 600m divers. Note that in Suwa’s 61xx GS line, there were 3 different levels of GS: "standard" GS (2A) in calibres 6145 & 6146, GS Special (3A standard) in calibres 6155 & 6156, and GS VFA (4A) in calibres 6185 & 6186. The 3rd digit of the calibre# was used to designate the accuracy standard which the movement conformed to. The 4th digit determined the type of display (5 = date; 6 = day/date). [Thanks to Don C for this summary of the GS levels.] According to the tech manuals, most or all of these are derived from the 6106 as the base movement.

In fact, at around this point, Seiko seems to be standardizing its movement numbers, with the xx06 in a series as the base, the 3rd digit representing the grade of movement (so a 6246 is higher than a 6206) and the 4th digit representing the display: 1 = no date, 5 = date only, 6 = DD).

At the same time, Suwa developed the 4005/06 Bellmatic. I don’t know if this is a completely new movement, or a derivative.

In parallel with this, Daini develops the 51x series, which includes the 5106 (1967) and 5146 Presmatic (1969), but also some Seiko 5 DX’s, the 23j 5126 and the 27j 5139. There is also the 5106 weekdater and the 5105 and 5125, about which the table has little info.

This brings us to 1968, when Suwa developed the 56xx high-end movement for KS’s, KS-Vanac’s and Lordmatics, and the 5641, 5645, and 5646 GS’s in 1970. This series was followed shortly by the 52xx series from Daini starting in 1969, which became the new movement used for KS’s KS-Vanacs, and Lordmatics. I believe both of these were hacking, autowind, and quickset. The 52xx later became the 4Sxx series. The Suwa Lordmatic (56xx) is manufactured to the Seiko "C" accuracy standard while the Daini Lordmatic Special (52xx) is "B" standard and runs @ a 28,800 bph beat rate (Suwa Lordmatic is not "high beat", I think 21,600 bph).

In parallel with the 56/52 series from Suwa, Daini developed the high-end handwind 45xx KS/GS series, a VFA version of which took 2nd place in the Swiss Neuchatel chronometer competitions. I wonder if in the late 60s, Daini had chief responsibility for developing movements for the Swiss competitions. This would explain their lower productivity in terms of new movements, as well as the various VFAs from Daini.

Note that the Daini 45GS "VFA" models 4520A & 4582A that were entered into the Swiss observatory contests were not "production" VFAs, but specially constructed models with accuracy & performance standards that differed from the "4A" (mens GS VFA) standard. KSeiya's article & chart show that quite clearly (for example, the GS VFA had a "Daily Rate" of -2 to +2 seconds while the Astronomical Observatory Chronometer used -8 to +8).

I have left out a few odds and ends, like the Advan, Actus, etc. Out of all these names, KS and GS seem to be the only names that stuck through the 1960s.

Regarding Advan, Don C summarizes various posts in the archives to say that they were "mid grade" modernistic style watches produced with 6106, 7019, & 7039 movements (thus being made by both Suwa and Daini divisions). Think of them as mid quality VANACs.

The Ascent of Quartz

The 6306, 6309, and 700x in the 1970s seem to have been the last mainstream mechanical movements. 630x were Suwa. 70xx were all Daini--the TZ movement table must have an error here: it lists the 7006 as Suwa, even though it was the base movement for the 701x’s. Thanks to John W. for clearing this up for me.

I am guessing that at this point, Seiko was shifting heavily to quartz and except for the divers, it seems they stopped making mechanical watches until the 1990s. They certainly had a number of firsts in the meantime, with the first quartz on the market, the first quartz chronograph, and I think the first watch with an IC (was this the 6M series)? Later came the Kinetic (autowind mechanism to charge a capacitor to drive the quartz movement) and most recently the Springdrive (mechanical, with a quartz oscillator to check the rate--charged via a Kinetic-like mechanism).

Sources

http://www.larrybiggs.net/scwf/index.php?mod=103&action=0&id=1080389175 and Isthmus's recent compilation: http://www.larrybiggs.net/scwf/index.php?mod=103&action=1&id=1154238086 as well as the Seiko movement table (http://www.timezone.com/library/extras/extras631803474986250000, which seems to be an improved version of the one at fortunecookie), have all been very helpful, and of course the search engine is a gold mine. The book "A Journey in Time" has been helpful on a few points, too, and this site: http://www.h4.dion.ne.jp/~smatic/ looks like a gold mine too--but begs a proper translation from Japanese to English, as I suspect the automated translations are losing a lot of good info. Thanks to Martback for pointing out this site. Another useful site re: the GS is from Seiya: http://www32.ocn.ne.jp/~kseiya/gs/ (thanks to jayhawk for pointing me to this one). Finally, a treasure trove of info can be found in the Seiko technical guides at: http://service.seiko.com.au/Service2/tg/index.htm Some additional info has come in from Don C. here: http://www.larrybiggs.net/scwf/index.php?mod=103&action=0&id=1155152249 http://www.larrybiggs.net/scwf/index.php?mod=103&action=1&id=1155305550
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