Seiko & Citizen Watch Forum Message Archive

A comparison between the 6105 and the 6309 was asked for a few days ago.

Basically, both in their design and engineering, these two calibers are just about identical. Although few parts interchange, the locations and construction of allmost all the parts are the same. With the exception that the 6105 is a date only movement, and the 6309 has both day and date. The most noticable difference would be in the keyless works of both watches, where the design has been economised in the 6309. In fact, thats the driving design ellement in the 6309, is an economising of the 6105. We see a few more plastic peices in the 6309, and most notably, we see some physical downsizing of three major components. The balance, the mainspring barrel, and the winding weight, are all just a bit smaller on the 6309, and it therefor has a somewhat shorter PR of aprox 45 hrs.

Infact, in specs, it would only be the PR, and the added day display that would note a difference. Both are auto winding offering neither hacking or handwinding. Both have 17 jewels. Both have a long history of providing service for years without need for attention.

Here are two shots of the two movements, where most of the physical landmarks can be seen to be simular.

Below, the 6306 or 6309. Although this is a 6306, you cant tell the difference between these two if only for the number on the winding bridge.

And below, the 6105B. This shot is out of the new Slick II, which is`nt finished yet.

Best regards,

Randall