Casio "G-SHOCK" The true value of the new generation Frogman armed with carbon fiber

In addition to the shock resistance that is at the core of G-SHOCK, the "MASTER OF G" is designed to withstand the harsh natural environments of land, sea, and air. The "Frogman" diver's model in the collection has captivated many G-SHOCK fans with its high performance and unique asymmetrical form since its launch, earning the trust of professionals based at sea. This new model features a carbon fiber exterior and a composite band, a first for the series. This gives the Frogman a fresh look while also improving its practicality.

Frogman's first composite band enhances utility

　The Frogman DW-6300, G-SHOCK's first diver's model, was released in 1993. It not only met ISO standards for water resistance to 200m, but also featured an asymmetrical form that allowed for unrestricted wrist movement during underwater activities. For nearly 30 years since then, G-SHOCK has continued to develop watches that meet the needs of divers.

　During this time, the Frogman has received a lot of feedback from users, and product updates have been made based on that feedback. One comment that stood out from the start was, "With standard bands that use buckles, the watch falls off when putting on or taking off while diving." There are many cases where the watch slips off from wet hands when trying to loosen the band after coming out of the water.

　To address this issue, the idea of ​​using a bracelet-type band that would prevent the watch from falling off the wrist even when loosened had long been floated. However, at the time, there were few types of resin available, leaving no choice but to use metal. However, the Frogman's large size meant that attaching a metal band would have adversely affected the weight balance, so this idea was ultimately abandoned. For this reason, the Frogman had long used standard resin bands, but with the emergence of a variety of reinforced resins and the increase in material options, as well as advances in resin technology, a project was launched with the aim of "creating a structure that would prevent divers from dropping their watches." Finally, in 2021, the first Frogman models equipped with composite bands were completed: the GWF-A1000XC and GWF-A1000C.

　The newly developed composite band features a hybrid design, with the outer H-shaped band made of urethane with a stainless steel core, and the middle band made of carbon-reinforced resin or fine resin. The structure of the middle band is particularly noteworthy. The GWF-A1000XC uses a material called "Pre-Creg" (CFUD), which is carbon fiber pre-impregnated with resin and is formed into a sheet with excellent unidirectional strength. This material is rolled up like plastic wrap or aluminum wheels to create a three-dimensional shape for the middle band, ensuring not only vertical strength but also pressure resistance, bending strength, and tensile strength. Furthermore, to address the weakness of Pre-Creg, which lacks the inherent pattern of the material, a plain-woven carbon sheet is wrapped around the outer periphery of the middle band for a more aesthetically pleasing appearance.

　Meanwhile, the fine resin used in the center link of the GWF-A1000C is a material that is highly biocompatible, making it suitable for use in watches, as evidenced by the fact that it is also used in medical artificial teeth. However, the shrinkage rate is different from that of ordinary resins, so a special mold is required for molding, and the molding machine also needs to be tuned, so the manufacturing process required a lot of trial and error. Kojima Kazuyasu, who was in charge of planning, explains: "Unlike materials used in ordinary industrial products, medical resins are indeed special. Many of the resins used at Casio are quite special, and the more we work with these functional resins, the more detailed reviews are required, including of mold technology."

　In response to requests from divers who wished to wear the watch over a wetsuit, the buckle specifications have also been revised for this model. While the double-adjust buckle, which allows for easy adjustment of the band length, has been adopted in the past, the extension mechanism, which allows for 13mm of extension and contraction by opening and closing the middle link, now incorporates a new ball plunger, improving durability even with repeated opening and closing. Furthermore, the inside of the buckle is equipped with a free-adjust mechanism that allows for 18mm of extension and contraction using a gear, and the plate material used here has been equipped with protrusions to increase its strength against twisting, thereby improving durability.

The inner part of the "GWF-A1000C" is made using fine resin. Here too, a pyramid-shaped sheet is attached to the outside of the part to add some decoration.

The inner layer of the GWF-A1000XC's middle section is made of a cylindrically wrapped pre-cut flex cable, which has excellent directional strength, and then pressed into a three-dimensional mold. The outer layer is made of a twill carbon sheet, which is not simply wrapped, but is also made through a laborious process of being impregnated with resin and then polished again.

　The resulting composite band not only eliminates the worry of dropping the watch when loosened, but also boasts an incredibly light weight and smoothly moving links for a comfortable fit. Furthermore, the durability of the buckle as well as the band itself has been improved, ensuring a quality that can be worn safely even while diving. This is an innovative band that combines the functionality and comfort required of a "MASTER OF G."

The extension mechanism of the middle block extends by 13mm when opened. The white sphere seen in the center of the photo is the newly adopted ball plunger, and this metal ball is operated by an internal spring, preventing deterioration such as the buckle opening or the protruding parts being worn down over time.

The inside of the buckle is equipped with a free adjustment mechanism that can expand and contract by 18mm. Previously, holes were drilled in the plate to allow it to slide, but this was not strong enough, so a new protrusion (bead) was added to improve durability.