Where there is a will there is a way. I have had that mindset for over 31 years in the injection molding trade
Toth Mold/Die Inc. has had some pretty tough parts to injection mold over the 31 years. There has not been a part that we had to tell a customer it could not be injection molded. We seem to have always found a way to do it. Some of the parts that come to mind that have been a challenge are parts that a lot of other injection molding shops turned away. At Toth Mold/Die Inc. we thrive on those kind of challenges.
About 4 years ago, I quoted and received a part to do for a pretty large company. The part was an overmolded Stator. It consisted of 28 laminated pieces of thin round washers that were .015/in. thick. Material was required to be molded over the stack-up washers. Those washers needed to be inserted into the mold and plastic was needed to be kept out of certain areas. Each washer had a tolerance of +/- .001/in. which means the overall height of the stack-up could be up to .056/in. difference and still be in tolerance. What needed to be done in the mold was to have a way to accept the different thicknesses of the washer and to be able to maintain the shut-off on the top and bottom of the part. The mold also had to have a spring-loaded plate to cast some very small detailed undercuts. I also forgot to mention that this mold was a shuttle mold that required two bottom halves that had to fit exactly the same with the one top half.
Another product that was a challenge for injection molding was a pair of sunglasses. Our customer wanted to be able to snap lenses in the frame. To achieve this, we had to injection mold a “V” around the whole shape of the lens. This “V” could not be cast the conventional way by slides or collapsible inserts due to the curve of the frame. We were able accomplish this by the use of hand-loaded inserts for each of the areas for the snap-in feature. Also, the cosmetics of the part had to be flawless which means no visible ejector pins were permitted on the temples or frames. This product was a big challenge that many molding shops chose to no quote.
These and numerous other challenging parts have kept things very interesting in the injection molding trade for Toth Mold/Die Inc.