Mold makers today strive to develop innovative solutions to make injection molded parts that are environmentally safe and cost less.
That innovation is driving growth among mold makers. According to Plastics News’ most recent North American mold makers raking, 139 companies reported $2.8 billion in related sales, up 7 percent over the previous year.
To be globally competitive, North American mold makers continue to look for ways to help customers gain efficiency.
One way is to speed the time to production. Mold makers produce prototype molds to evaluate marketing projections and expectations for a new product, and to launch a product. That can help mold makers shorten design time by creating an example of the mold so they can get a vision of what a product is going to look like. It also drives custom designs because the speed to market is much better.
3-D printing traditionally can make quick and inexpensive prototypes to produce concept models and perform fit and functionality tests.
For the injection molding process, molds are typically made by milling out steel blocks. As metal is removed, it forms the shape of the cavity to the design of the plastic part to be produced.
As the mold maker removes metal, this means more plastic ends up in the part. While removing metal is simple, putting it back is virtually impossible.
Mold makers find it easier to mill a smaller amount of metal out of the mold and add less plastic. If someone decides that something must change, it’s always better to be adding more plastic into the final part (removing metal). This is called a “tool-safe mold change.”
Mold makers use highly automated wire EDM and CNC equipment, or even complete manufacturing cells, that can machine and precisely measure each step in the process.
One emerging technology is laser ablation, the process of using a laser to remove very, very fine slices of steel. The particles are burned away because the slices are so small and the machine moves quickly. It enables mold makers to create intricate patterns.
Laser ablation is an alternative to the chemical etch process, and it can increase quality and repeatability. It is computer-driven and computer-processed. For example, if a customer gives a company the electronic file, it can be shared across divisions, which allows two sites to use the same equipment to develop the exact same mold.