Reaction Injection Molding Process VS. Other Processes

Reaction injection molding is cost-effective for the production of a few hundred to several thousand parts. Benefits include low-to-moderate tooling costs, short lead times, the ability to produce large and lightweight parts, parts with tight tolerances, enhanced design finishes, chemical resistance properties, 94V-0 and HB ratings, customized part properties, and wall thickness, as well as the ability to mold over metal, wood, glass, computer chips, and other parts.

RIM Advantages VS. Injection Molding

Reaction Injection Molding Advantages

Large, lightweight parts
Varying wall thickness with no sink
Deep draw
Can combine multiple designed parts into one part within a single mold
Low-to-moderate cost tooling – machined aluminum
Short lead-time
Tooling can be used for prototype and easily modified for production parts
Material flexibility – elastomers, solid RIM, structural foam, flexible foam, DCPD, etc.
Encapsulation of component materials including metals, electronics, plastic, valves, circuitry, etc.
Low-to-high production volume
Tight tolerances
Injection Molding

Small-to-mid size parts
Requires uniform wall thickness
Limited draw
Multiple mid-size parts generally require multiple molds
High-cost tooling – steel
Long lead-time
Prototypes require different tooling and tooling modifications are expensive
Limited material options
Limited encapsulation
Moderate-to-high production volume
Tight tolerances

RIM Advantages VS. Thermoforming & Vacuum Forming

Reaction Injection Molding Advantages

Complex geometry and cosmetically appealing parts
Deep draw with structural integrity
Varied wall thickness throughout the part
Structural integrity molded into parts
Molded-in attachment points
Tight tolerances
Low-to-moderate cost tooling
Low-to-moderate production
Material flexibility – elastomers, solid RIM, structural foam, flexible foam, DCPD
Encapsulation of component materials including metals, electronics, plastic, valves, circuitry, etc.
Thermoforming & Vacuum Forming

Simple part design and geometry
Draw limited and requires post-molding structural features
Requires uniform wall thickness
Post-molding gluing of ribs
Glued attachment points
Low-to-moderate cost tooling
Limited material flexibility
No encapsulation capability

RIM Advantages VS. Sheet Metal

Reaction Injection Molding Advantages

Tremendous design flexibility
Large and light-weight parts
Structurally strong and durable
Molding in color an in-mold painting
Variable wall thickness within the same part
Affordable part cost
Capable of combining multiple parts into one integrated part
Provide sound and vibration insulation
Corrosion and rust-resistant
Part cost is more stable 
Sheet Metal

Limited design flexibility
Parts are heavy
Post-painting required
High part cost
Varied wall thickness requires welding multiple parts
Multiple parts require labor and assembly costs
Structurally stronger parts
Part pricing is less stable due to the commodity’s market

RIM Advantages VS. Cast Molding

Reaction Injection Molding Advantages

Cosmetically appealing parts right out of the mold
Prototype tooling can be used for production parts
Tight consistent part tolerances
Variable wall thickness without sink
Tooling lasts the lifetime of the project
Short lead-time on tooling
Cast Molding

Cosmetic inconsistencies of parts of the mold
Prototype and production tooling are different
Part tolerance varies from part to part
Variable wall thickness generally includes sink
Short lead-time on tooling

Contact RIM Manufacturing to Start Your Next Project

When You Consider All the RIM Advantages, We Know You’ll Have the Best Reaction. RIM Manufacturing is the Partner Uniquely Positioned to Accelerate Your Company’s Success!

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