Continuing our exploration of the right molding process for part design (“Determining the Right Molding Process for Part Design”), this blog entry considers RIM Molding vs. Structural Foam Molding.
Reaction Injection Molding (RIM) is a low cost tooling process geared towards high quality Polyurethane and Urethane plastic parts with Class A surfaces. RIM Tooling especially molds of Aluminum is lower in cost than other plastic manufacturing methods. However, based upon a variety of raw materials, architectural detailing, painting and finishing requirements, the price per part may be slightly higher. The diverse functions and project freedoms are why more designers and OEM’s are turning to the RIM process as a preferred solution.
Structural foam uses essentially the same process as regular Thermoplastic Injection Molding, so the design considerations of using the Reaction Injection Molding process versus structural foam are similar, but the costs are different with added foaming agent. Thermoplastic structural foam molds require higher process pressure and cost roughly double that of RIM molds, while the structural foam parts tend to be lower in cost. The decision here often relates to quantities.
Other Design Considerations: While RIM is the more cost-effective option for low volumes, structural foam molding can be used for jobs with higher quantities where higher tooling costs are offset by lower part costs. Neither process is the best for production of high volumes.
Read more about it in our white paper, “Determining the Right Molding Process for Part Design. How RIM Molding Advantages Compare with Traditional Production Technologies”.
Download the paper at (www.exothermic.com).