Koonze Model now offers insert molding as part of our injection molding services. We can also machine custom metal and plastic inserts in-house using our CNC capabilities. Upload your CAD files for a free insert molding design review and quote—our injection molding experts will get back to you within 24 hours.

Custom Overmolding Services

Q: Thermoplastic Injection Molding

Koonze Model delivers high-quality injection molded parts in as fast as 10 business days. Our network of manufacturing partners supports everything from rapid prototyping molds to production-ready tooling. We offer full injection molding capabilities, including insert molding, complex undercuts, and internal or external threading.

Q: Range of Mold Making Options

Our trusted partner network lets us turn your 3D part data into high-quality injection molds fast. We handle everything from design to manufacturing for tools, dies, and molds—whether for prototyping or full production. We also offer plastic blow molds, aluminum and steel tooling, plus 2-shot and 3-shot molding. And with Koonze Model, you own your molds, with maintenance services available through our partner network.

Q: What materials can be used for overmolding?

We work with a wide range of materials, including TPE, TPU, and other elastomers for the overmold, and rigid plastics or metals for the base. Our team can help recommend material pairings for the best adhesion and performance.

Q: Do I need to supply the insert part, or can you make it?

We can machine custom inserts in-house using CNC or mold around off-the-shelf parts you supply. Either way, we’ll help make sure they’re mold-ready.

Q: How strong is the bond between the two materials?

That depends on the material pairing and design. With proper surface prep and compatible materials, overmolded parts can achieve excellent mechanical and chemical bonds that hold up under stress.

Q: What’s the typical lead time for overmolding projects?

Lead times vary based on part complexity and volume, but most projects move from design review to molded parts in 2–4 weeks. Rapid prototyping options are also available.

Bring your multi-material designs to life with our fast, reliable overmolding service. Seamlessly combine rigid and soft materials with tight tolerances and crisp finishes. Ideal for functional prototypes, low-volume runs, and early-stage validation.

Start A New Overmolding Project

Start to Upload Your Files

Upload 3D CAD files (STEP STP SLDPRT IPT PRT SAT IGES IGS CATPART X-T OBJ STL files) or common formats like Word, Excel, PPT, and images.

Custom Overmolding With Koonze Model

Koonze Model offers precision overmolding services that bring together multiple materials into a single, cohesive part. Whether you’re combining hard plastics with soft-touch surfaces or adding seals and grips to complex components, our process ensures tight bonding, smooth finishes, and repeatable quality.

Ideal for functional prototypes or low-volume production, our team supports you from DFM through final delivery. With fast turnaround times and engineering support at every step, Koonze helps reduce assembly steps, improve product durability, and enhance user experience.

Start A Overmolding Quote >>

Overmolded Parts Gallery

Explore examples of precision overmolding across a range of industries—from soft-grip handles to multi-material housings. Every part shown was built for durability, fit, and performance.

Why Choose Koonze Model's Overmolding Services

Fast Turnarounds

We move quickly—whether it’s prototypes or production tools—so you can hit your deadlines without compromise.

Tooling Expertise

From simple molds to complex multi-shot tools, our team has decades of hands-on experience in mold design and manufacturing.

End-to-End Capabilities

We handle every step in-house, including CNC machining, insert prep, and final molding—ensuring quality and consistency.

Clear Communication

You’ll always know where your project stands. We keep communication clear, fast, and focused on your goals.

Get a Fast Overmolding Quote

Upload your CAD files and tell us your material and insert needs—we’ll get back to you with a quote and design feedback within 24 hours.

GET A FREE QUOTE

Koonze Model's Overmolding Finishes

Overmolding Design Tips

Proper overmolding design ensures strong material bonding, reduces defects, and improves part performance. Follow these key guidelines to optimize functionality, durability, and manufacturability.

Design Element	Recommendation
Wall Thickness	0.060″ to 0.120″ (1.5 mm–3 mm) generally provides the best bonding.
Corner Radii	Maintain a minimum of 0.020″ (0.5 mm) to reduce localized stress.
Thick TPE Sections	Core out thick sections to minimize shrinkage, reduce weight, and shorten cycle time.
Blind Pockets or Ribs	Avoid deep or un-ventable blind features in your design.
Wall Transitions	Use gradual transitions in thickness to improve flow and avoid defects like gas traps or backfills.
TPE/TPV vs. Substrate	Keep the overmold thinner than the substrate to reduce warpage, especially in flat or long parts.
Material Bonding	Select overmold materials that enable mechanical or chemical bonding with the substrate.

Other Types of Injection Molding at Koonze Model

In addition to overmolding, Koonze Model offers a range of injection molding solutions tailored to different production needs. From insert molding to high-volume multi-cavity runs, we help bring complex designs to life with speed and precision.

Thermoplastic Injection Molding

Insert Molding

Range of Mold Making Options

Ready for Full Injection Molding Support?

From prototyping to high-volume production, our injection molding services are built for speed, precision, and flexibility. See how we can help bring your parts to life.

Explore Injection Molding Services