May I know what is the difference between 8R28 automatic and 6S28 automatic??
That's a great question. I've wondered the same a few times but despite the wide spread use of the internet as a very effective marketing tool by the Swiss brands, the amount of information available on these 2 Seiko calibres is really minuscule. That pretty much sums up the problem with Seiko, their lack of PR competency in the international arena.
Whatever little information that I managed to dig up in these 2 movements are summarised below:
6S28 - Some say that this is a more economical version of the 6S37 design which was supposedly sold to Tag Heuer.
34 Jewels
28,800bph
Column wheel with vertical clutch system
Accuracy: -15-~+ 25sec per day
Power Reserve: 50 hours
Sub dial configuration: 6-9-12
8R28 - Latest automatic chronograph from Seiko launched in 2008
34 Jewels
28,800bph
Column wheel with vertical clutch system
Accuracy: -15-~+ 25sec per day
Power Reserve: >45 hours
Sub dial configuration: 3-6-9
Remarks: The 8R28 incorporates a major innovation in automatic chronograph design, a single piece 3 pointed hammer which is used to instantly reset all 3 chronograph hands in unison. It also features 3 vertical clutches, one each for the second, minute and hour hands respectively. Conventional chronographs have only 1 vertical clutch, for the second hand only.
Last but not least, for comparisons sake:
6S37
40 Jewels
28,800bph
Power reserve indication
Column wheel with vertical clutch system
Accuracy: -10-~+ 15sec per day
Power Reserve: 50 hours
Sub dial configuration: 6-9-12 with PR indicator at 3 o'clock
