In plastic injection molding, the number of items that can be molded in one shot using one mold is called the number of cavities. The number of cavities can be from 1 to a reported maximum of 216. Since the number of items molded in one shot becomes large as the number of cavities becomes large, it is possible to reduce the cost of production per item. However, as the number of cavities becomes larger, there is a trend of […]
Tags: Injection Molding, Plastic Parts
Making injection molded prototypes is both an art and a science. High levels of technical expertise and attention to detail are required to prevent small mistakes from costing companies big money when it comes to mass-production of novel parts. Preventing such a circumstance is all about highly competent design. This article discusses some of the molding defects that can occur in a part during injection molding, and ways to fix and avoid them. Design shortcomings we will discuss include: Flow […]
Tags: Injection Molding, Plastic Parts
Troubleshooting flash is complicated, and often there is a lot of tail-chasing on the shop floor in trying to get a solution. This approach should lead you to the solution via a data-driven procedure. Testing the parting line, using pressure-indicating paper: The image on the left is flash-free. The part on the right side is flashed; note the location of flash where the paper is mostly white at the top and bottom. The white color indicates the parting-line touch force […]
Tags: Injection Molding, Plastic Parts
Designing plastic parts is a little different from designing metal parts. There are many things that must be carefully considered and planned for. Plastic parts can be made in many ways: injection molding, thermoforming, extrusion, blow molding, even casting. For the sake of brevity, this article will focus on one type: injection molding. If you’ve ever built a plastic model kit, you’ve seen and know at least something about injection molding. It is a process where heated (molten) plastic is […]
Tags: Plastic Parts