January 10, 2022

Custom Injection Molding Expert Tips — How to Start Your Project Off Right

There is often a desire to jump right into the manufacturing stage as soon as a new part idea is pitched and approved. And while plastic injection molding can fabricate the idea of a part into a finished piece quickly, efficiently, and cost-effectively, there are several key decisions and considerations that help facilitate that process before jumping right into molding. These steps are necessary, as they help shape a part to be precisely finetuned for its specific use or application, and they cut down on the need to refine the design or retool the mold once production has begun. So make sure each project starts on the right foot by applying these injection molding expert tips before manufacturing begins.

Design Considerations

Every project starts with the design, and the decisions made in the design phase are critical for plastic injection molding success. Because many of the design choices made during this phase will have a significant impact on how the part is molded, manufactured, and finished, as well as how the part will ultimately function.  

For instance, this is point where the right material for the project is chosen. Each type of plastic resin has its own strengths and weaknesses, and choosing one type over another can alter the finished look, feel, and finish on a molded part. Furthermore, specific application or industry specifications may limit what types of materials are suitable for a particular part. And whatever choice is made may affect how the mold for the part is designed — such as adjusting for gate placement to account for pressure or injection flow speed.

Other important considerations during this phase include: 

  • Wall thickness — a uniform thickness throughout the part reduces warping, sinks, air gaps, and blemishes during molding.
  • Gate location — gates should be placed in areas to best avoid obstructions, voids, and sinks, so consider placing the gate away from the core and ejector pins, but closer to the heaviest cross section(s).
  • Radius of edges — introducing rounded edges helps reduce stress concentrations and decreases the potential for fractures and cracks during molding

Mold and Part Considerations

There are a variety of molding techniques, and some work better for specific parts than others. Often, the complexity and nature of the part will inform the best molding technique to employ. 

Parts that require non-plastic components to be inserted or attached can benefit from Insert Molding, where the plastic part is molded around the non-plastic portion. This helps save on finishing and assembling costs, and allows parts to be used immediately after molding. Alternately, for parts that require two different types of textures or weights or hardness within the same part, Multi-Material Molding — or Two-Shot Molding — would be the ideal choice. This allows sections of a part to be molded from two different resins at once and joined during the molding process to create one cohesive part from the materials. 

But molding technique goes beyond the ways of combing multiple materials together. There are also more sophisticated techniques employed by Hansen Plastics to ensure expert part quality and pristine design fidelity. Scientific DecoupledSM Molding is an advanced molding process utilized by HPC to integrate software from RJG with transducers placed within the mold, allowing operators to precisely control pertinent variables during the molding process — namely pressure, temperature, and fill speed. This allows for unparalleled accuracy during the molding process to ensure each part is molded as expected, dramatically reducing the chance of defects, short shots, and material waste.

Plastic Injection Molder Considerations

Choosing the right partner for injection molding will determine how well each part is manufactured. Because the injection molding process is complex, and the infrastructure used to mold parts requires a dedicated team that can ensure quality production runs. Which is why teaming with Hansen Plastics Corp is an expert choice.

Hansen Plastics utilizes a combination of dedicated value streams, RJG Scientific Molding, and lean production workflows to most effectively run their more than 70 on-site presses. This allows their employee-owners to offer the full spectrum of in-house engineering and tool design, quality testing, value added secondary services, and inventory management in addition to their injection molding capabilities. But deeper than that, Hansen Plastics takes a genuine in the success of the businesses they partner with, working to ensure that their customers receive dedicated service, precision manufacturing excellence, and cost-effective molding solutions to meet their budget needs and business goals.  

The team at Hansen Plastics is focused on creating trust and respect with customers, providing guidance throughout the entire injection molding process. This helps HPC ensure satisfaction, long-lasting partnerships, and sustainable, profitable growth for their customers. These values are held by each employee-owner of HPC as they extend a welcoming hand to all new clients and opportunities. 

For over 50 years, Hansen Plastics has been committed to building fruitful relationships with customers founded on respect and trust. HPC understands this requires an unwavering dedication to quality and consistency in injection molding, to establish and retain that foundation with all HPC customers. If you are looking for a trusted, experienced plastic injection molding manufacturer to handle your products, reach out to HPC today, or visit HansenPlastics.com for a full view of Hansen Plastic Corp’s capabilities.