Everything You Need to Know About Plastic Injection Molding

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Plastic injection molding is a good way to assemble pieces of plastic to make an object. There are some aspects about it that people overlook.

Design Decisions Determine 70% of Manufacturing Costs

Design decisions determine 70 percent of manufacturing costs. If you have a product that is going to be made by injection molding, it is essential that you follow the right procedures. These guidelines will help you avoid the most common defects and reduce your manufacturing costs.

The first step in designing a part is selecting the material. There are many types of plastics. Selecting the right one for your product requires a lot of experience and discussion.

Another design consideration is whether your part has overhangs. Typically, it is better to design your part without any overhangs. This will cut down on the number of molds required. In addition, the parting line can be adjusted to make it less complex.

You also need to consider the material for the surface finish. The finish of your part will affect the overall cost and quality. Some materials require special attention to provide a cosmetic appearance.

Other factors that influence mold design include undercuts, cams, sliding side-actions, and hand-loaded inserts. Bosses are another important design element that is often used in injection molded parts. They are cylindrical projections with holes that are designed to receive threaded inserts and other fastening hardware.

Reprocessed Materials May Spoil the Original Properties of The Plastics

One of the most daunting tasks in the modern-day manufacturing plant is the sorting out of the many different types of raw materials. Plastics are amongst the most ubiquitous, but they are often in short supply. Among the plethora of polymers is the tamer known as polyethylene, an often-cited example of the tetrad. Typical use for the aforementioned material is in the form of packaging, for both goods and services. Using the aforementioned polymer in this manner can result in the re-use of the plastic in an efficient fashion. The obvious downside is that the re-use of the aforementioned polymer is a major contributor to greenhouse gas emissions in the US. Other notable examples include the use of the aforementioned material in the manufacture of various plastics found in consumer goods such as beer and wine bottles, and in the manufacture of food and consumer products. Besides the usual suspects, a number of unintended side effects have also been reported.

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How Do I Know if Plastic Injection Molding is Right for My Project?

Before you begin manufacturing a component through plastic injection molding, there are a few points you need to keep in mind. These include the following:

1. Keep in Mind the Cost

You will have to figure out how many components you need to produce for you to make your plastic injection molding process the most cost-effective way of producing those parts.

After that, you will have to figure out how many components you need to manufacture in order to break even. This will include the cost of distribution, marketing, assembly, production, testing, and design, as well as the anticipated price point for sales. Start by creating a narrow margin and increase gradually as needed.

While working out the costs, keep in mind the price you will have to pay at the beginning. You need to figure out what amount you will have to pay as initial investment for preparing a product for plastic injection molding that will help manufacturing.

2. Keep Design Considerations in Mind

Keep plastic injection molding in mind from day one when you start designing the component. If you minimize the number of components and simplify the geometric design from the get-go, it will pay off over the long term.

When you design the mold tool, preventing faults during production should be your main priority. You can use a moldflow software such as Solidworks Plastics to run simulations and consider gate locations.

3. Minimize Cycle Time and Assembly Process

You need to minimize the cycle time as much as practically possible. To do this, use machines that have the hot runner technology, which will help with designing ingenious tools. If you need to see a huge difference, take a few seconds off your cycle time – it will translate into huge savings when you start manufacturing components by the millions!

Another aspect is the assembly process. Your component should be design in a way that minimizes the assembly process. The cost of assembling simple parts during an injection molding run is minimal, which is the primary reason why plastic injection molding is done in Southeast Asia. You will save huge money on the cost of labor, as much as you are able to design assembly out of the process.

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The Bottom Line

Plastic injection molding is a great method for finishing production on a big scale. You can finalize prototypes used for product testing and/or consumer testing using this method. You can use 3D printing in the early design stages as it is more flexible and affordable than injection molding. For the best plastic injection molding services, contact PTMS.