The reasons for a high-gloss finish in plastic molding vary. Some examples include extreme transparency of the molded part, reduced localized corrosion or highly crack-sensitive tooling (due to design or operational stresses). Then there is the impact of mold surface finish on injection molding productivity, as the release forces of the plastic part from the [...]
Automotive headlight housings have evolved from round, stamped steel assemblies to thermoset parabolic reflectors with diamond-like angles, covered with clear lenses. Today‘s BMC (bulk molding compound) reflectors are cosmetic parts with complex curves and shapes. Their parabolic surfaces are the aiming mechanisms for the light. With the move to clear lenses, any imperfections in the [...]
Overmolding is an injection molding process used to mold one plastic (commonly a rubber-like plastic called TPE) over top of another component (substrate). The substrate is usually an injection-molded plastic part, but it could also be made from various other materials. Overmolding is used across several industries and serves a wide array of purposes. Below [...]
Over the past decade, soft-touch overmolding has radically changed the look, feel, and function of a broad range of consumer products. Abundant new color, texture, and tactile options are available in such products as toothbrushes, razors, power tools, cameras, kitchen items, hand-held electronics, and auto-interior parts. Driving this change is the increasingly diverse range of [...]
Traditionally drawings have been an indispensable and unambiguous definition of the finished product—a vital part of the service agreement between the customer and those responsible for tooling and inspection. Unfortunately, for many shops, 3D models are still only a supplement to the official authority of the drawing. However, a growing number of companies involved in [...]
Injection molders quote or estimate a job based on six primary factors: part weight, material cost, machine size, cycle time, labor requirements and packaging. The material and packaging costs are relatively easy to obtain from suppliers, which makes them fixed values—not estimates. Thanks to solid modeling software programs, part weight is also a fixed value, [...]
It seems there are a lot of classes and programs available that you can earn the title of ‘expert’ in a few short weeks or months. While that may work for a some jobs, a mold designer needs to have a substantially more experience to earn the reputation on an expert. If you’ve ever wondered [...]
Injection molding is one of the leading processes for manufacturing plastics. It is widely used for mass-producing identical parts with tight tolerances. It is a cost-effective and extremely repeatable technology that yields high-quality parts for large series production. It is a fast, intensive process where high heat and pressure are involved to inject molten material [...]
Mold builders encounter many challenges when deep-hole drilling, including hole straightness, poor cutting tool life and excessive time spent in the hole. Troubleshooting these challenges requires a look at correct coolant flow, pressure and chip evacuation but begins with understanding the limitations of the cutting tools, toolholders and machines. Time—whether spent in the hole, changing [...]
Proper mold venting is essential for producing quality parts. During the molding process, the air contained in the mold needs a way to escape, otherwise the melt will compress and trap that air in the cavity. A combination of melt pressure and high temperature will then ignite the oxygen (called the “diesel effect”), causing burnings [...]