We're Your Plastic Molding Company

RSP offers high quality custom plastic injection molding to bring your vision to life. Whether you need to create a fully functional prototype or large volume production, we can make it happen. 

Integrating 50+ years of manufacturing knowledge with current best practices and technology, we offer a variety of injection molding services and value-added processes to meet all of your needs, from single components to full custom turnkey manufacturing. 

Our state of the art plastic injection molding and assembly facility in China provides affordable tooling and molding while meeting the United States' manufacturing practices and quality standards. We take pride in our socially responsible and environmentally friendly facilities. 

Injection Process: From Pellets to Product

Turning plastic pellets into a perfect molded product is what we do best. It may sound like a fairly simple process, but details are everything when it comes to the plastic mold injection process. Here is a quick and simple overview of how we take your design from pellets to product. 

The first stage of the process begins by feeding dry plastic pellets, held in a "hopper", into a heating cylinder by using a hydraulic pump, motor and gears. Within the cylinder there are multiple heating zones which systematically increase the temperature of the material as it moves closer to the gate where it is injected into the tool. Each heating zone is constantly monitored and adjusted. The peak temperature of the plastic depends on the combination of materials being injected, but can reach as high as 725° F. Here at RSP, our average melting temperature of materials is 525°F. 

With the help of a stationary and movable platen, the mold is held in place as a nozzle prepares to inject the molten plastic. Next, a clamp mechanism closes the mold halves. The action is performed by a motor rated by the maximum amount of force the machine is capable of creating. Then, the molten plastic is injected into the mold as the clamp keeps the mold closed. As the product solidifies and cools down, the finished product is ejected from the mold. 

As discussed above, the typical injection molding machine consists of five major components: 

• Hopper
• Heating Cylinder
• Hydraulic Pump, Motor and Gears
• Stationary & Movable Patens
• Clamp 

In-Mold Decoration

For some projects, there may be a need for In-Mold Decoration (IMD) to include an image or coating on a plastic surface. This process involves printing a high-quality image on a heat resistant plastic film that will hold up to the stress of in-molding. The printed film is inserted into the open plastic injection mold and held in place via vacuum ports or electrostatic charge while the mold is closed. Once closed, plastic resin is injected into the mold, thus encapsulating the label to the finished part. Combining the decoration process with the molding process adds durability, decreases manufacturing costs by eliminating post-molding labeling, handling and storage, and also allows for design flexibility. IMD allows for a wide range of colors, effects, textures, graphic options and can replicate stainless steel, wood grains and carbon fiber. IMD is commonly used used on washers and dryers because of its affordability and durability.  

A Seamless Process

In order to provide a low-cost product with minimal set-up, quality and precision, we practice a seamless process to get the job done right the first time. If you are interested in our plastic injection molding, in order to start the project off on the right foot, please provide the following. 

1. Request a Quote
2. Provide Drawings/Files

To ensure the integrity of your product, we recommend providing drawings/files in any of the following: 

• IGS/STEP/STP (preferred format)
• Solidworks
• AutoCAD
• PRO-E

If the above file formats are not available, we can produce a model from your sketch or drawing. 

Once each party agrees RSP is the best partner for the project, an official order can be placed. This will then launch the design for manufacturing review where we consider all the best practices of molding and design to optimize the model. Once design suggestions are discussed, the engineer team at RSP begins the creation of a 3D model of the tooling This 3D model will need to be approved by you before proceeding further, ensuring your quality standards are being met every step of the way. You can expect to receive weekly updates on tooling status including photos during the tooling phase of your order. 

A few other things to note: