Reaction injection molding (RIM) is a popular part molding process used in a variety of different industries such as the medical device, electronic, IT, laboratory equipment, and defense industries. It involves injecting a liquid chemical mixture with a low viscosity into a heated aluminum mold, where it will expand and harden to form strong, lightweight parts.
Because the part molding process you choose can have a substantial impact on cost, quality, appearance, and design, it is important to be aware of the positive and negative aspects before making a decision. Here are some of the key pros and cons of reaction injection molding to consider.
Pros of Reaction Injection Molding
Design Freedom: One of the main benefits of RIM is the design freedom that it offers. By providing the unique ability to create walls with variable thicknesses, encapsulate metals and electronics, and mold in attachments, RIM offers unparalleled design flexibility.
Low Tooling Cost: Because the reaction injection molding process takes place at low temperatures and pressures, it does not require a highly durable tool like most other molding processes. Instead of expensive metals such as steel, RIM uses tooling made from low-cost aluminum, greatly reducing the tooling costs involved—especially for larger, more complex parts.
Aesthetic Appearance: Largely in part to the amazing design freedom RIM offers, choosing RIM for your production process will allow you to create parts that have a sophisticated, aesthetically appealing appearance.
Cons of Reaction Injection Molding
Higher Individual Part Production Cost: While the tooling cost of RIM is lower than other molding processes, the individual part production cost is generally higher. As such, RIM is not ideal for parts that need to be produced in very high quantities.
Lead Time: To create a high-quality product, it is important to make a high-quality mold. However, doing so can take several weeks or months. Those on shorter production timelines may benefit from choosing a process with shorter lead times than RIM.