Yes Virginia, you can do it on your own. It's not rocket science and you don't need some overly-specialized tools. If you have patience, pay attention to what you're doing and don't cut corners, anything simple like changing a battery or swapping a strap is easy peasy. But you will need a few tools. On this article I'm going to cover the bare-bones basics that you would need for a simple job like that, that will take you five to ten minutes. In future articles I'll go over some more specialized tools that you will need to do the job better and for some other more complex stuff. I'm no watchmaker, not even an engineer or with any kind of tech degree. I just like tools, G-Shocks and to tinker with my stuff. And Lego. So if I can do it, so can you.
But first, a few words about tools in general. First of all, there is a saying that goes "You should use the right tool for the right job", and that's absolutely true. Yeah, you can use your trusty Swiss Pocketknife to open a G (trust me, I have quite a few of them and it can be done), but you don't want to, unless you're in a real pinch. Try to get the best suitable tool for the job that you can possibly find. Second, G-Shocks were made to be used, but even though I really wear all of mine, I will not abuse any of them if I can avoid it. So even though a $5 eBay tool kit in theory (and being honest, in practice too) can do the job, if you want to keep your watches scratch & dent free, you should invest a little in some good quality tools. Nothing that I'll show in these articles are really expensive or made of unobtanium, so please try to get some decent stuff. If you have access to the interweb (eBay will suffice 90% of times) you will find plenty of quality tools for a very good price.
Yep, that's it. Three drivers (four with the Allen head driver), tweezers and a spring bar tool. For this article I'll show a simple strap swap, so you will only need the drivers pictured. Tweezers aren't exactly necessary for a strap job, but I like to have them around to handle small parts, like the spring bars.
Let's start with the drivers. The majority of screws used by Casio on the external parts of a G-Shock are Phillips head, so if you have a #0 and a #00 size drivers you're good for about 80% of all jobs. Mine are German from Wiha, and I have a very high respect for the brand. They're easy to find on eBay and are very affordable, so if you can, it will be a great buy. Once again, those el-cheapo-$5-a-dozen tool sets will work, but I rather spend a bit more and have reliable tools that if treated with the proper care will get inherited by my son.
On the first pic you probably noticed that there's an Allen head driver there too, and I said that 80% of your needs would be covered by Phillips head drivers. Well, here's part of the 20% of cases that would not be covered by Phillips drivers. I'm going to swap the strap of my vintage Muddy DW-8400, and that's one of the few models where Casio did not use the regular Phillips head screws. I have an Allen driver set also from Wiha, and in this case I'll need the 1.5 mm driver. For most of all G-Shocks, you will just need the Phillips #0.
All G-Shocks have the bezel attached to the case by screws, usually four, one in each corner. Some models you don't have to mess with the bezel screws, but in a few of them, like with my Muddy, to have access to the spring bars, you have to remove the bezel. So after you remove the bezel, here's what you get:
Here we have another curiosity, and so far I've only seen this on the 8400: the access to the spring bars is from the top, and not from the bottom of the watch, like most other models. But the work is the same: the spring bars are those two silver pins that you see sticking out of the strap into the case. So how to get the spring bars out? With a spring bar tool.
I use the one on the left and it's model FB-504 (you can find it at Otto Frei), and it's more then worth it's weight in gold. It's easy and practical to use, and it makes the job a LOT easier. You just have to compress the extremity of the spring bar inwards, using the small forked point, so that the pin comes out of the hole in the clasps. Some people have even made a spring bar tool from an old small flat head driver where they file a notch in the tip. On the pic you can see one that comes in those el-cheapo-$5-a-dozen tool sets, but it's made of soft steel and doesn't fit easy in the space between the clasp and the strap. The one on the right is one that came with one of my Orient divers, and it's quite good, but a bit too bulky for G-Shocks.
And here's the straps off. Then I just cleaned things up and put the straps in place, also using the spring bar tool - fit the spring bar inside the strap, and compress one of the extremities with the spring bar tool until it snaps into the hole inside the clasp.
Done! Vintage Muddy with brand new (and now correct) straps.
See? Easy peasy .
By Luciano U. Werner