Smart Molding International 1-2022

28 molding technologies smart_molding international 1/2022 viscosity and stored material param - eters to regulate the changeover point freshly from shot to shot. For silicones, this is important insofar as the batch fluctuations are much more dramatic than for conventional ther - moplastics. First LSR project for medical technology As the first LSR project, Lender and Scheuerlein selected a plug with a part weight of 0.5 grams that can be used in medical technology. To date, these have been produced from solid silicone (HTV). There are relatively few types of this material that are approved for medical uses, making the switch to LSR an attractive option. However, the latter has very low viscosity, which makes moldmaking extremely difficult. At a water-like consistency, the molds have to be per - fectly sealed. Usually, a vacuum is even applied. The temperature control is the reverse of that used for thermoplastic processing to prevent premature wet - ting. While the plasticizing unit as well as the cold runner is cooled, the cavity is brought to a temperature of approxi - mately 190 °C. To date, most mold production for LSR has been in the hands of highly specialized providers centered re - gionally in Austria. However, because these providers are increasingly man - ufacturing silicone parts themselves and, furthermore, the prices for molds and cold runners are relatively high, more and more companies are looking for alternatives. Toolcraft is also going to build its own tooling, drawing on its in-house experi - ence with precision molds. Currently, about 50 percent of what Scheuerlein's team produces is for its own use, with the other half going to customers. Of course, plans call for offering LSR molds to external customers in the future. Support to the last detail SKZ will receive internal and exter - nal help in the coming trials. A training manager at the SKZ location in Horb (in the Black Forest region) got his start in the silicone processing industry, an ideal set of circumstances. Despite this, Cordula Wieland, the KraussMaffei ex - pert for thermoset plastics, is able to supply plenty of tips and tricks. One such "hack" is the recommen - dation to purchase a chest freezer. Particularly in the experimentation phase – where a few weeks might pass between steps – freezing the unit in the meantime saves a good deal of work. The top team from SKZ and Toolcraft will pave its way forward with support from KraussMaffei. KraussMaffei – Pioneering Plastics KraussMaffei is among the world’s leading manufacturers of machinery and systems for the production and processing of plastics and rubber. The company's brand has been synony - mous with cutting-edge technology for over 180 years. The range of services covers all areas of injection molding machinery, extrusion technology and reaction process machinery. KraussMaffei www.kraussmaffei.com Lively discussions were the hallmark of the three-way meeting between SKZ, Toolcraft and KraussMaffei held to mark the beginning of LSR processing: Markus Scheuerlein, Cordula Wieland und Georg Schwalme (from left) During the tour of the SKZ there was much to talk about