Jaeger-LeCoultre watch crystal material

　　Jaeger-LeCoultre watchesis a watch loved by many people today, so do you know what theJaeger-LeCoultre watchescrystal material is like? Let's take a look together.

　　How to identify three types of watch crystals

　　First, you can gently tap the crystal with your finger and listen carefully to the sound. Acrylic crystals produce a plastic-like sound, whereas glass has a more solid tone. Secondly, you can judge by weight: acrylic is the lightest, while sapphire crystal is the heaviest. Because sapphire has excellent thermal conductivity, it will feel cool to the touch. Furthermore, sapphire crystals are far smoother than the other two materials; if you place a drop of water on a sapphire crystal, the droplet will not easily spread out, whereas on other materials it will flatten across the surface.

　　Classification of Jaeger-LeCoultre watch crystal materials

　　Sapphire crystal: physically and chemically stable, with a hardness second only to diamond. It resolves issues such as scratching, ageing, and corrosion, though it is brittle.

　　Plexiglas: also known as synthetic glass or acrylic. It is prone to scratches, but has good toughness and is shatter-resistant.

　　Mineral glass: offers fairly good scratch resistance and superior vertical impact resistance compared to sapphire crystal, which is why military watches frequently use it for their crystals.

　　Jaeger-LeCoultre watchesHow to replace the crystal

　　The watch crystal of a Jaeger-LeCoultre timepiece is an exterior component, positioned in the most prominent area and most vulnerable to external friction and impacts. Due to its material and location, the crystal is one of the most easily damaged parts of a Jaeger-LeCoultre watch. Any lost, broken, or cracked watch crystal must be replaced according to the original specifications.

　　When replacingJaeger-LeCoultre watchesthe watch crystal, the primary considerations are the outer and inner diameters. The inner diameter should be just right to accommodate the tension ring, while the outer diameter must fit tightly with the case. As long as these two conditions are met, the brand name does not matter. Between these two measurements, the outer diameter is the most important; a slightly smaller inner diameter is acceptable. Because an open tension ring can be used—by trimming a small section from the opening—it can be fitted into the Jaeger-LeCoultre watch crystal without affecting the replacement.

　　When replacing a Jaeger-LeCoultre watch crystal, you can fit the crystal directly into the case bezel by hand. The method is as follows: after removing the damaged crystal, clean the bezel groove, fit the tension ring into the inner rim of the new crystal, and then insert the crystal into the case bezel. Once three-quarters of the crystal has entered the bezel groove, support the case back with the four fingers of your left hand while firmly pressing the center of the crystal with your thumb. Use your right thumb to push the remaining edge of the crystal—which has not yet entered the groove—into the recess until the entire perimeter is seated inside the case groove. It is best to use a crystal press with nylon dies, as this ensures even pressure across the crystal and allows the edge to be pressed into the case groove in one motion. However, you must select the correct inner and outer diameters, otherwise, the crystal may crack. It is advisable to perform a dry test fit by hand without the tension ring first; if it fits, the outer diameter is correct, after which you can install the tension ring and press it into the watch using the press. This is a mineral glass crystal. The hardness is low, and it is easily scratched. It is recommended to apply a protective film to the crystal.