What rules must be followed to optimize the geometries of a prototype so that they are immediately suitable for injection molding?
What are the essential precautions to refer to?
There are very verbose and detailed technical manuals that give a whole series of theoretical tricks on how to design a 3D solid so that it can be injection molded without serious aesthetic or mechanical problems.
We do not want to offer you a manual but our direct experience in the concrete support we give to our customers in the optimization of geometries for injection molding.
In the event that the design of the object is born within the COESUM group, most of the work is done directly by our designer because he is already very knowledgeable on the subject and is in constant dialogue with our mechanical designer. However, it may happen that we receive an aesthetic design that is already “frozen” from the client company that only asks us for specific advice on the optimization of the geometry with a view to mass production from injection molding. This is what happened with the customer Tellspec, a company based in the United Kingdom, who asked us to intervene on their Preemie Sensor product. The Preemie Sensor scanner, designed by Alessandro Spalletta and Massimiliano Datti, allows the analysis of the composition of breast milk and suggests the necessary additions based on the baby’s personal nutritional needs, relating them to the growth of premature babies. The simplified interface, the small size design and the reassuring appearance make it suitable for use in both the medical and private sectors; characteristics that have earned him several worldwide awards for design and product innovation.
The focus of our intervention on the Preemie Sensor was the external shells and their coupling and assembly with the internal cradle that houses the battery and electronics. We have revised the coupling system of the two bodies and inserted pins in correspondence with flexible columns with the aim of limiting the effect of crushing and non-harmonic bending of the upper shell with the lower shell.
The upper body was also studied in the visible aesthetic part. The particular curved shape required in fact an accurate simulation of the mold-flowing to avoid that it had too evident mold opening lines.
Where possible we have proceeded to thicken the walls or to simplify the internal structure for housing the electronics and the battery.
A series of brass inserts allows assembly with metal screws from the outside for the complete closure of the Preemie Sensor.
The optimization project was successful and the company also asked us for support in the production of a first series from plastic molding for placing the product on the market. The best technology in terms of material quality, reliability and mechanical performance is that of prototype molds.