What is a 'screwback'? And does it matter?

[JokerNJ]

From time to time, you may see posters referring to 'screwback' G-shocks with some affection!
The original DW-5xxx series of G-Shocks - the first Gs really - had a caseback design known as the screwback. This series until the DW-5600e had the same type of design.
The screwback was and is still popular on dive watches.

Basically, the original G-shock design had the module - or main body - of the watch in a stainless steel case. The back of the case was screwed on to the main body a little like a bottle top. There was a rubber gasket to help seal the back.
These are screwbacks.

Later G-shocks have modules/bodies that are made from resin/polycarbonate rather than stainless steel. Instead of the back of the watch screwing directly on to the body, the back plates are held in place by four screws - one at each corner.

On the photo attached, the right hand watch is a DW-5600c-9V and is a screwback. Note the notches around the edge of the back - these are for the tool that removes the screwback.

The left hand watch is a GW-M5600 and the back plate is held in place by the philips-head screws on each corner.

Whether screwbacks are any better is an ongoing debate! They certainly feel tougher, heavier and are generally more desirable. They're also generally made in Japan.
Models like the Frogman (with titanium instead of s/steel), the GW-5000 (with DLC - diamond like coating) and the Giez use the screwback design and are priced accordingly.

EDIT: Adam in NYC posted a thread listing screwback models. Link: List of screwback G-Shocks.

[BenL]

Whether screwbacks are any better is an ongoing debate!

+1 You can say that again. There certainly are a lot of mixed views on this topic.

[sl8763]

Good summary Joker. If I may add:

One disadvantage of the "four screws" caseback is the very real possibility of wearing down and stripping the screw heads, particularly with repeated openings of the watch. Quite easy to do, and the screws are not easily replaced, particularly on older or discontinued models. With the screwback, unscrewing it it requires a case opener, but these tools can be had for cheap on eBay (and yes, although they are mass-produced overseas, even the basic three-pronged model works well enough).

[G-Shock Absorber]

I know there is a debate to be had about whether the screwback design offers any significant advantage(s), but I wonder; is anyone prepared to put forward an argument for why the non-screwback design might be better? I mean apart from the price of such models being lower.

Personally I love the screwbacks on my GW-5000-1JF DLC, DW-5000C, and Frogmans, and I wish Casio would make a Mudman with a screwback, but just now I thought I'd turn the question on its head and see if the more recent design actually has any non-cost-related advantage that I and others might have overlooked.

[WillyLix]

I still need to get me a screwback.

[NeedAG]

Left, a recent G-7100 plate back. Right, a 1990 DW-5900 screw back.

[Kashio]

Learned something today!

[Cockpit]

I know there is a debate to be had about whether the screwback design offers any significant advantage(s), but I wonder; is anyone prepared to put forward an argument for why the non-screwback design might be better? I mean apart from the price of such models being lower.

Personally I love the screwbacks on my GW-5000-1JF DLC, DW-5000C, and Frogmans, and I wish Casio would make a Mudman with a screwback, but just now I thought I'd turn the question on its head and see if the more recent design actually has any non-cost-related advantage that I and others might have overlooked.

One non cost-related reason for a non-screwback will be to accomodate a unique watch shape design. Examples of some watches are the ATC-1200 and DBC-610. Also, take a look at the picture NeedAG posted above. If the manufacturer wanted to make the G-7100 a screwback, due to its shape and module design, it would either have to enlarge the overall size of the watch or miniaturise/redesign the module in order for the screwback to cover the area of the module for water resistance.

By the way NeedAG I don't think the watch on the right is a DW-5900.