In my last King Seiko Guide I described how the the King Seiko brand was conceived by the Daini Seikosha factory in 1961 as a luxury watch brand to rival Suwa Seikosha’s Grand Seiko line established in 1960. We also saw how the unnumbered movement from that first King Seiko model would go on to become the caliber 44, a movement that proved accurate enough to eventually be incorporated within the very Grand Seiko lineup that it was designed to rival. Part of my guide looks at the successor to that all conquering movement.
In the mid-1960s, both factories were participating in the Swiss chronometer trials as a way of pushing themselves to greater achievements. The focus was on long term accuracy, since the trials lasted many days, so both factories began experimenting with high beat movements as a way of achieving this accuracy over a longer term.
In Search of More Accuracy
In 1966 both Daini Seikosha and Suwa Seikosha brought high beat movements to Neuchâtel for the first time and the resultant improvements in accuracy were dramatic. Daini’s 36,000 vph ‘052’ high beat caliber performed far better than the previous 18,000 vph ‘965’ caliber and took 9th place overall. The previously highest place had been 114th achieved by Suwa Seikosha in 1965 so the move to high beat movements clearly reaped accuracy benefits.
Both factories went on to experiment with even higher beat movements in 1967. Suwa submitted movements running at 54,000 vph and 72,000 vph, while Daini submitted movements running at 36,000 vph and 72,000 vph and also tested, but did not submit, movements running at 180,000 vph! During the competition, Daini found the 36,000 vph movements performed better than the 72,000 vph versions. Therefore, it is perhaps no surprise that Daini Seikosha’s 1968 replacement for the 44KS was a high beat movement running at 36,000 vph.
Caliber 45 was a completely new design for Daini. Certain concepts were carried over from the 44KS, such as being manually wound to provide a lower profile, and having a more stable balance bridge secured at both ends rather than a balance cock secured at just one. In most other aspects however, the movement was all new. It was produced in five versions:
- the base no-date 4500 movement
- the 4502 with a newly developed instant date change mechanism
- the higher grade 4520 used in the Grand Seiko 45GS
- a higher grade 4522 with the same instant date change mechanism
- An even higher grader 4580 used in the rare Grand Seiko 45GS VFA (Very Fine Adjusted)
As well as running at twice the rate of the earlier 44KS, the 45KS gear train was also unconventional. The barrel drives a tiny center wheel, an intermediate wheel and a large off-center driving wheel combination. This then drives the third, fourth and escape wheels. The second hand is then driven by another center wheel driven indirectly from the second wheel. Drive is transferred to the dial via a cannon pinion attached to the tiny center wheel deep inside the movement.
An ‘indirectly-driven’ wheel is one driven by a wheel in the train but it itself is not part of the train because it does not transmit power in to a neighboring wheel. A ‘directly-driven’ wheel is one the is part of the train because it is both driven by the previous wheel and also transmits power to the next wheel in the train. A directly-driven wheel in the train will always have torque acting up on it from the main spring even when the train is locked by the escapement. An indirectly-driven wheel only receives torque when the train is unlocked and moving.
In the 45KS movement above, we can see that the uppermost center wheel  is driven by a pinion on the the second wheel  but it does not mesh with any other wheel and so is indirectly-driven. The lack of permanent torque on this center wheel can be seen as a slight wobble or shimmy on the otherwise smooth high-beat sweep of the 45KS second hand.
The need for the unconventional and somewhat complex going train was perhaps necessitated by the extra strong mainsprings Daini fitted to these movements to drive the balance at 36000 vph. Most high beat movements have small balance wheels but for the 45KS, Daini fitted a relatively large balance wheel that required a lot of torque to gain the amplitude required.
The additional torque generated certainly causes some reliability issues with these movements now that they are 50+ years old. It’s not unusual to see teeth on wheels or pinions snapped clean off because of the high torque loads. The high torque can also damage the barrel with broken teeth or teeth ground down by the much harder small center wheel. Thus it is important when considering the purchase of a 45KS, to know that it has been serviced recently and is running well. If the watch is a non-runner and needs a new barrel, then it may take weeks to find a replacement.
45-700x / 4502-700x
The first King Seiko models to feature the new movement were the no-date 45-7000 and the with-date 4502-7000 models introduced in 1968. The case design was clearly evolved from the earlier 4420-9990 with very similar ‘wings’ extending from each upper lug to the lower lug either side of the central cylinder. These wings would form a staple of King Seiko case designs going forward, featuring both in the 56KS series that sold alongside the 45KS series and in the much later 2001 SCVN001 re-issue.
The dials were very similar to the 44KS dials featuring the same white sunburst base. The applied rhodium plated markers were elongated on the 45KS dials and now featured a black stripe on top for improved visibility. The hands also received the same central black stipe as the markers. The hands were also more simply made lacking the machined edge bevel of the previous generation. The King Seiko script was also retired with the 45KS series, replaced with a simpler ‘KS’ logo at 6 o’clock above the all new ‘HI-BEAT’ text.
In 1969, gold reappeared in the King Seiko line up with the gold plated versions of the 45-7000 and 4502-7000. Hands, markers, Seiko and KS logos were also gold plated. Casebacks are marked SGP for ‘Seiko Gold Plating’ but the cases were not as durable as the earlier gold cap King Seiko cases. Subsequently, expect most SGP KS45s you see to have worn cases with the base metal showing through on the case edges.
In 1970, these two models would become the 45-7001 and 4502-7001 respectively. At this time the crown changed from one with with a pronounced conical center section to one with a much smaller step. The caseback text was also changed from ‘Water Proof’ to Water Resistant’ in line with mandated labelling changes made across all Seiko model ranges at around that time. Later still, in 1973, the 7001 case itself changes shape around the undercut area with the previous small step being made larger and the thickness of the wing sections reducing to make space as the following case end projections illustrate:
Cosmetically, the dial is identical between the two versions and the dials of the 45-700x and 4502-700x models remained the same for the lifetime of the model. The dial code of the no-date 45-700x is 45-7000T AD while the date version is 4502-7000T AD. Also unchanged through the model lifetime was the design of the medallion which was changed from the outgoing 44KS ‘Seiko’ version to the new ‘KS’ branding. The Daini lightning bolt logo was prominently moulded into the medallion below the large KS.
The 45-caliber King Seiko watches came with black leather straps and a new style of pin-clasp that again incorporated the new ‘KS’ logo.
The 45-700x and the 4502-700x remained available in both stainless steel and gold plate until 1974.
45-7010 / 4502-7010
Launched a year after the 7000 model in 1970, the 7010 provided the same no-date and with-date watches in a more conventional brushed oval-shaped case. While the 7010 models have the same markers as the 700x versions they also have either a white or silver linen-textured dial labelled with either a 45-7010 or 4502-7010 dial code. The minute hand is also changed to narrower, all-black version.
45-8000 / 4502-8000
The third case style used with the 45KS movement was the 8000 model. The case had an extremely ovoid shape that now, with the benefit of 50 years of Seiko designs and nomenclature, we would probably describe as a large square ‘turtle’ case. The case is mirror polished on top and finely brushed on the sides with a sharp transition between the two. Unfortunately now, 50 years later, many examples have now been incorrectly brushed on top and horribly over polished on the sides.
The model was initially available in early 1969 with a steel case with the same textured dial and hands as the 45-7010/4502-7010. Later in 1969, an alternate silver linen dial was made with square markers. In 1970, the silver dial of the square-marker variant was replaced with a charcoal grey dial that continued to the end of 1972. For 1970 only, a gold-plated version that reverted the dial back to the 45-7010/4502-7010 design but now with gold-plated dial, hands and markers.
Stylistically, the case of the 8000 model deviated from the King Seiko design language used up until then, which had represented a slow and steady evolution from the first King Seiko case. The 8000 was the watch with which the King Seiko brand welcomed the funky 1970s and made a break with the styling of old. Things would get even funky and crazier for the brand as it evolved away from Grand Seikos shadow into something stylistically unique for the remainder of the 1970s.
45-8010 / 4502-8000 Chronometer
The 45KS movement gave rise to another chronometer grade watch to follow on from the eariler King Seiko 4420-9990. By this time, the King Seiko chronometers were being independently certified by the Japan Chronometer Inspection Institute (JCII, established December 1968) to the same level as the old Swiss standards. At that time chronometer grade was defined to be a mean over five positions within -1.0 to +10.0 seconds/day which corresponded to Seiko’s internal ‘A’ grade accuracy. This independent certification lead Seiko to mark the dials with ‘Officially Certified’
Seiko also differentiated those watches that performed to the higher ‘AA’ accuracy grade which was aligned with the then Grand Seiko standard which since 1966 had been defined at -3 to +6 secs/day. Some 45-8010 examples met this higher ‘AA’ grade and were marked both on the dial and on the case back medallion with the words ‘Superior Chronometer’. All superior chronometer movements appear to have been manufactured in mid-1969.
All 45-8010 watches were produced in stainless steel only, with a white sunburst dial. Although turtle-shaped, the 8010’s case is quite different from that of the 7010, especially from the side. Where the 7010 had long lugs similar to the 7000, the 8010’s lugs are short and stubby with the case flanks angling down sharply forming a convex pebble-like shape. The hands are also unique to the chronometer model with the central black stripes typical of the 45KS models but with straighter, less sword-like hands.
The 45KS range of King Seiko watches are important from a collecting perspective. Firstly, the range has a strong connection with the 1960s Swiss chronometer trials, the movement being a direct development from the advances made in those competitions. In many enthusiasts opinion, caliber 45 is one of the great movements to be produced by Seiko. Certainly the inherent quality of movement is proven with many examples being certified to A (Chronometer) and AA (Superior Chronometer/GS) grade accuracy. The movement was also promoted to the Grand Seiko range as well, culminating in the AAA grade 4580 VFA movement. From a personal perspective, my 45KS examples are some of the most accurate in my collection, combining great movement design with the positional stability of a high beat movement.
Caliber 45 was also the last hand assembled King Seiko movement as the models that came afterwards were built on automated production lines. Perhaps, this means that the 45KS has a little more connection in collector’s minds with the Daini Seikosha artisans more than subsequent models. It is also the one and only high beat movement from the Daini factory and was also their last purely hand-wound movement.
The movement does have its reliability achilles heal as mentioned in the relatively fragile gear train compared to the power of the mainspring. I would not say that every 45KS is a ticking time bomb but there are plenty of examples out there with barrel and gear teeth damage. Thankfully the 45KS movements were never rare with many thousands made so while NOS parts are close to non-existant, there are plenty of potential parts donors out there with good movements but damaged dials and over-polished cases. The advice is, if possible, do not wind it fully to avoid full torque being applied through the gear train. The latter takes some experience but with time, one gets the feel for the mainspring and can regularly stop winding before the mainspring hits its stop within the barrel.
Of the 45KS models, the 7000 seems to be the most common in the market place with the 8000, particularly the gold plated version, being the least common. The 7000 case style is the most obviously influenced by Tanaka’s Grammar of Design approach and that accounts for its ongoing popularity. The chronometer models, including the superior variant from 1969 (a small number are dated Jan through Mar 1970) are easily found although most cases have had their fine brushing polished away by now.