Recently I decided to attempt an upgrade on my Tough Solar G-SHOCK watches through hydro modification. There are a number of existing hydro mod threads on F17 and various methods to accomplish this mod. I will breakdown the method I used, which was heavily influenced by kevio. So far, the 4 watches I hydro modded have not leaked at all. To my eye the LCD clarity and contrast is significantly enhanced. The numerals are much darker, especially in low light.
I have successfully performed this modification on the following models:
I'll do my best to breakdown the hydro mod execution through step-by-step explanations including pictures of the aforementioned models. This particular hydro mod method does not include a bubble.
I have a random smattering of pics of each of my hydro mods because the mod is a messy endeavor. So taking pics with my iPhone while performing the mod was a random affair. I will include links to my flickr albums for each of the respective hydro mods at the bottom of this post. Hopefully you will find some cohesion in the following description of this mod:
Open the caseback and remove the module
Fill the case about halfway with silicone oil
I use this 100 cSt silicone oil
Use a spudger tool to push all the bubbles out from under the solar panel. I used two spudger tools, one to push the bubbles out and another to remove the bubbles at the top of the oil surface.
Once all the bubbles are gone, insert the module and repeat the process. Seat + align the module and make sure the button pushers are all squared away. Add more oil to cover the module completely. Then work on getting all the bubbles out by depressing the module with the spudgers. This process takes some time and patience, but it is worth it to remove all the bubbles.
Place and align the cushion/spacer on top of the module and add more oil. In this pic the spacer is plastic. It is the same in the GW-6900. However, in the GW-M5600 and GW-B5600, the cushion/spacer is rubber. I will address this difference after the hydro mod breakdown.
Same procedure. Spudger the bubbles out. Add more oil. Next step is to apply the caseback and seal the watch. Before doing that, seat the o-ring and add some oil to the reservoir area of the caseback. Some of the oil in the caseback will inevitably run off the caseback when it is turned over to apply to the watch case. That is fine and likely unavoidable. The key is to fill the watch case and caseback with as much oil as possible so there are minimal pockets of unused space once the watch is sealed. For the GW-5000 I finger tightened the screwback caseback until it was relatively tightened. Then I cleaned the caseback with a paper towel and tightened it to completion with a jaxa tool.
The whole process is messy at times. I used a paper plate with a paper towel on it to soak up the oil that ran over the watch case throughout the mod. All four of the hydro modded watches were free of bubbles and are leak free to date. For more views of each of the watches before and after the hydro mod, feel free to peruse the following flickr albums:
Quite a bit of concern has been discussed on F17 about how the rubber version of the rear cushion/spacer absorbs the silicone oil. The rubber cushion/spacer then expands and creates problems with how the o-ring and caseback seal the watch case. I was aware of this phenomenon when I began the hydro mod and closely monitored both watches for about a week after the mod. Some advice that kevio offered to me is to leave the resin bezel and strap off of the watch for a few days after the hydro mod so one can examine how well the watch is taking to the hydro mod. Luckily, neither of my watches with the rubber cushion leaked and continue to be sealed completely. This seems to be true with solar + atomic watches, whereas models with the rubber cushion in the DW-5600 series seem to be problematic. I did take great care to seat the o-ring as I sealed the caseback on all of these hydro mods.
I am quite happy with how the watches turned out after hydro modding. All of the watches are significantly enhanced in my opinion, specifically when viewing the clarity and contrast of various properties of the LCD. Layers within the LCD seem to be exaggerated, and numerals are darker when viewed in any environment (low light and bright light). The least upgraded watch is the GW-B5600BC-1B. In hindsight I would not hydro mod this watch since the solar panel is cutout around the area of the LCD that can be viewed. As a result, the numerals of the GW-B5600BC-1B are not really changed at all, especially compared to the dramatic difference the GW-M5600, GW-6900, and GW-5000 numerals show. Despite that, the solar panel of the GW-B5600BC-1B looks pretty cool hydro modded so I am fine with it. I am not going to bother with undoing the GW-B5600BC-1B hydro modification.
Hope this is helpful to anyone considering a hydro mod on a GW-M56XX, GW-69XX, or GW-5000.
Low light comparison of hydro modded GW-M5600 on the left and OE GW-M5610 on the right:
GW-6900 hydro modded
OE GW-5000 LCD on left, hydro modded GW-5000 on right
GW-B5600BC-1B hydro modded