Can you find the micro part in this picture? It's the tiny nub sticking out to the left a little below the end of the runner. The mold maker, Miniature Tool and Die Inc. in Charlton, Mass., calls it "the smallest part in the world." It weighs just 0.00012 gram. That's the kind of size scale being explored by a handful of intrepid molders and mold makers. As you'll learn from Senior Editor Mikell Knights' cover story, it's a realm as far from normal injection molding as the top of Mt. Everest.
Donna Bibber, v.p. of sales and marketing for Miniature Tool, told me something about the challenges involved in this proprietary application. "We started with a subgate," she explained, "but when the mold opened we were left wondering, where did the part go? So we switched to an edge gate." That way, the customer can use the runner to handle the part through an automated assembly process.
Aside from the technical hurdles, micro-molders may face another kind of challenge—making an adequate profit to cover the risks of entering new territory. They probably cannot get by on selling machine time by the hour—not with the fast cycles used to mold these flyspeck parts. Nor can they follow some other molders in marking up the raw material—not when 520 parts can come from a single pellet! No, they'll have to price their services, as more molders should, on the basis of special skills, value added, and just plain nerve to try something that's a little "out there."