This project started about a month ago after I won an aution on a GWM5600BC composite bracelet to put on my GW7900B.
To begin, I really like the GW7900b negatives display, especially after hydro modding it, and I rely on the tide graph a lot while fishing. I fish the Indian River and Sebastain Inlet here in Florida and fishing at the inlet is heavily governed by the tides. After installing the the bracelet I wasn't satisfied with how it looked. I had to remove the wings and the bracelet was so small in comparison to the bezel. I then tried the bracelet on my brothers GW6900 and it fit and looked perfect. I also like how much lower the GW6900's profile was.
Now if only there were a 6900 series that had a tide graph... So I won an auction on eBay for a GLX6900. First thing I noticed about this watch was the glossy resin, and I cannot say how much I detest it. So I ordered a GW6900 bezel and in combination with the 5600BC bracelet I was satisfied for a while. I like the alarm on the GLX6900 and G7900, but they don't display neap and spring tides(high and low tides that don't fluctuate much), nor are they solar/atomic. SO I STILL WAS NOT SATISFIED.
My ideal watch would be a solar/atomic, tidal graph with neap/spring tides, negative hydro modded display, with a GW6900 profile and metal/composite bracelet.
But it did not exist until now.
So I did a little research on removing the glass/crystal from a G Shock and I removed the module from the GLX6900, removed the buttons, removed the inner trim bezel, and pushed out the glass. I used a C clap and 2x4 about 16 inches long(so I could rest it between my legs) to hold the case. I cut it out with a hole saw, going from big to small and so pulled the leftover chunks out. The wooden piece that goes between the glass and the C clamp is a chunk from a furring strip(1x2) cut out with a hole saw. Then I just pushed it out. No cracks or scratches. Now I had a clean case to work with.
I repeated that whole process with the GW7900.
The buttons are ok to remove, I used a very fine pick. THEY ARE A PAIN TO ASSEMBLE THOUGH!!! Use care and everything will go well, just don't expect to rush through it.
To put everything back together I first in stalled the solar panel, then the glass,crystal. I used a thin coating of contact cement around the edge of the hard rubber/plastic seal around the glass and then I just placed the glass on the table with the solar panel positioned correctly, placed the case on top and applied even pressure on the case with my palm. It was a little tricky, the top or bottom want to go on before the rest.
Once the glass and solar panel were seated, I put a few drops of 15wt silicone R/C shock oil(I used Team Assosiacted stuff) on the glass/solar panel. Then I put the inner bezel in and put a few more drops of oil in. After re installing the side buttons I filled the case up with oil and let it sit for a half hour. I filled a small open glass cup with oil and placed it under a 40w incandescent bulb to get it to about 90-105 degrees(used a wireless thermometer) and submerged the case in the oil. assembled the module and back plastic piece and worked out any bubbles. I let it sit far about an hour then heated up the oil with case and module in it back up to about 100 degrees and reassembled the back plate.
Put the bezel and bracelet on and was done. Now I have, in my opinion, the most personal and unique G Shock there is. At any rate, it is the EXACT G shock I wanted from Casio, without having to wait for them to release it.
I hope this helps anybody trying to do anything similar. If anyone has questions ask away, I will help as best as I can.