Plastics Mold

Plastic Mold Making

Injection molds, or molding tool, are the formed halves that come together in the injection molding machine to be filled with molten plastic and produce the plastic parts in their image. The cavity side, or “Movable” side, is typically the half which will form the “best” surface of the part, and the core side, or “Fixed” side, will typically show the visual imperfections caused by ejector pins because the parts get ejected from this half.

Additional complexity can be added to injection molds in order to produce more complex plastic parts. To accommodate part features such as undercuts, molds can be augmented with side-pull mechanisms called slider. Slider moves into a cavity in a perpendicular direction from the draw of the mold halves to form the undercut feature, then stationary angle pins on the stationary mold half pull the slides away when the mold is opened. The pins enter a slot in the slides, and cause them to move backward when the moving half of the mold opens, like a cam. Then the part is ejected, the mold closes, and the slides move forward along the angle pins as a result of the closing action of the mold.

Injection molds are usually constructed from hardened steel or pre-hardened steel. The choice of mold material is determined by the number of parts to be produced. In general, hardened steel molds cost more to construct, but their longer lifespan will offset the higher initial cost over a higher number of parts made before wearing out. Pre-hardened steel molds are less wear-resistant and are used for lower volume requirements or larger components; their typical steel hardness is 38–45 on the Rockwell-C scale. Hardened steel molds are heat treated after machining; these are by far superior in terms of wear resistance and lifespan. Typical hardness ranges between 50 and 60 Rockwell-C (HRC). The molds can be manufactured by the combination of CNC machining, EDM sinking, Wire cutting, Polishing, Mold fitting & assembly processes.

With decades of mold making experience, GEMS understands a broad and relevant Steel and Resin portfolio in the material properties and appliances industries, and owns unparalleled expertise in helping customers achieve greater design flexibility and enhanced product specifications. GEMS is at the forefront of the manufacturing industry, providing innovative parts & products which help customers set their brands apart in these ultra-competitive markets.

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Integrated Factory Resources

We are your one-stop manufacturing solution provider for customized products with the joint effort & support from our 120 partnership subcontractors mainly for the production of metals & plastics. We can expand much faster but the top management decide to keep GEMS a compact, dedicated and professional company, which allows our team to really focus and deliver on your projects without any excuse or compromise. We strive to be a long-term, reliable and trustworthy partner of our customers rather than just being a contractor, and look forward to growing the company with customers’ success.

Manufacturing Veteran Team

With the passing years, we are proud to build up a manufacturing veteran team with rich experience and full expertise to fulfill your specific demand. From mold making, injection molding, die casting, stamping and sheet metal, to 2nd processes like CNC machining, oil spraying, powder coating and chrome plating, and then assembling and packaging and related, we always have someone in house to be an expert to resolve the issues in different stages of product development. We also specialize in providing charger, cable and hub, plus other electronic accessories that support a complete set of product.

Strong Project Management

“Think global, execute local” is the principle of our work. Time, quality and cost are the three key elements to be considered throughout the product development from concept design to mass production. A detailed plan with weekly conference call update is a critical gateway to ensure these three key elements are successfully implemented, also assuring that all parties are on the same page. Communication is the Secret to Success . Everyone works independently to take care his own job, but together we are a team to get things done and are your daily eyes and ears onsite in China.

Flexible Operation & Customization

We offer a wide variety of products, such as mold, component and assembly product, and certain value-added services. For logo or branding product, we have in house resources to complete a color mix that can perfectly match a brand’s unique colors in fast and cost-effective way. Understood the client needs production parts but having a hard time to find a vendor since the order quantity is as low as 1000 or lower. GEMS is well set up for low volume injection molding or die casting projects. Surely our team is also capable of building SPI Class 101 mold that is designed & made for 1 million cycles or more of producing the same high quality parts consistently.