TRUMPF Laser's headquarters are also in Schramberg and the two neighbours have worked together in the past. Two old but very robust TRUMPF marking lasers have been used in the Junghans production for decades. But TRUMPF had to go one technological step further for the anniversary watch. The reason: "Platinum is the most valuable precious metal in the watch industry and is difficult to process. So I wanted to play it safe for the engraving as well," says CEO Matthias Stotz. Junghans decided on a new laser procedure from TRUMPF for engraving the high-quality platinum watches
Junghans engraves the watch backs in a TruMark Station 7000 which is equipped with a TruMicro Mark 2030. The pulse duration can be set variably between 400 femtoseconds and 20 picoseconds. The result: burr-free, deep engravings as well as exquisite, whitish engravings. The aim was to achieve an engraving depth of 17 micrometers for the anniversary watch. Deep enough for an exquisite appearance but not so deep that too much valuable precious metal is removed by the laser. The desired depth is engraved first using a higher pulse rate, then a fine molten film is generated by quickly changing the process parameters in order to lighten the engraving. Switching between the process parameters such as the pulse duration takes less than 800 milliseconds.