Flash, or flashing, refers to excess plastic that leaks from molds in the plastic injection molding process, and hardens as the plastic cools. The removal of these bits of extra plastic is called deflashing, and is commonly performed by mechanically cutting, breaking or grinding away the excess plastic to create a finished part. In large injection molded parts, deflashing is fairly straightforward. The specifications for a uniform finish are measured in centimeters and flash removal can be performed with traditional CNC machining methods.
When it comes to precision micro parts, however, flashing presents additional challenges. As dimensions and tolerances shrink, the accuracy of the deflashing process becomes problematic. Each precision micro part must perform identically, which means each part needs to be produced to exact specifications with minimum variability. At micron levels, the profiles of the excess plastic on injection-molded parts are not uniform. Every part is significantly different and deflashing cannot be automated using traditional methods.
To address this micro manufacturing challenge, Microlution has pioneered a micro deflashing solution that rapidly measures each part after molding occurs and uses the measured profile to mill each part to precise specifications. This solution integrates a 2D laser displacement sensor that measures each part, collecting topography data in real time. The part and the measured data are automatically passed to the micro milling tool which generates G-code from the data and mills each part to the desired specification. All of this takes place at high speeds and high throughput, dramatically accelerating cycle times compared to using a separate deflashing process.