3D printed flexible workpiece mount for conventional polishing

The full aperture polishing process is a very important step in manufacturing precision optics. For this the brittle glass workpiece needs to be mounted to a specific holder in order to install the lens in the polishing machine. One very common way is to use a precision holder which is machined to the exact diameter of the lens. This precision holder is mostly made from aluminium which leads to inherent difficulties in the combination with the workpiece. The brittle glass on the hard holder surface tends to chip at the corners when not handled carefully. Also, the friction between aluminium and glass is relatively small which may lead to a relative motion in the holder and therefore scratching of the surface. Another aspect is that for each lens diameter a holder must be manufactured. Therefore, more time is needed for the preparation for the process and the efficiency of the optician’s shop decreases. At the TC-Teisnach Optik, we use a commercially available, low-priced 3D Printer in order to manufacture an additional flexible part between lens and holder. This solves the problems which stem from the encounter between two hard surfaces. The friction between holder and lens is increased and the handling is simplified, since the flexible part reduces the risk of edge chipping. Additionally, this brings the possibility to use one aluminium holder for a variety of lens diameters by exchanging the 3D printed part. With this technology a 3D printer with flexible filament acts as a useful extension of an opticians’ shop and can improve the efficiency.