Custom Overmolding Services

Rigid Substrate. Soft Overmold. One Part, No Assembly.

Texas Injection Molding delivers custom overmolding services — bonding a soft TPE or TPU overmold directly onto a rigid plastic substrate in a single injection molding operation, eliminating adhesives, fasteners, and secondary assembly for products requiring multi-material integration.

Custom Overmolding Services

Overmolding bonds two different materials into a single part — typically a rigid engineering thermoplastic substrate and a soft elastomeric overmold layer — without adhesives, mechanical fasteners, or secondary assembly operations. The result is a part with a rigid structural core and a soft, grippy, or aesthetically differentiated surface that performs as a single integrated component.

Texas Injection Molding produces overmolded parts for OEMs across medical devices, power tools, consumer goods, and industrial equipment — wherever ergonomics, sealing, vibration damping, or multi-material aesthetics are design requirements. Our overmolding services cover substrate molding, material selection and compatibility validation, overmold tooling, and production.

Material compatibility validation before tooling

Overmolding Capabilities

Multi-material injection molded part production for ergonomic, sealing, vibration damping, and aesthetic applications.

Soft-touch grip overmolds on rigid handles — power tools, medical devices, consumer appliances

Elastomeric sealing overmolds — integrated gaskets and seals on connector housings and device covers

Vibration-damping overmolds on industrial equipment handles and housings

Color-accent two-material parts for consumer product aesthetics

Waterproofing overmolds on electrical connectors and outdoor equipment

TPE and TPU overmolding on rigid substrates for soft-touch grips, seals, vibration damping, and impact protection

Overmolding Quality & Bond Integrity

An overmolded part that deaminates in service is a product failure. Bond integrity between substrate and overmold is the defining quality requirement of every overmolding program.

Material compatibility validation — substrate and overmold material pairing tested for bond strength before tooling commitment

Bond strength testing — lap shear, peel test, and environmental conditioning on qualification samples

Mechanical bonding design features — through-holes and undercuts as backup to chemical bonding for critical applications

Gate location designed to ensure overmold material reaches the bond interface without premature freeze-off

Material Compatibility

Not all substrate and overmold material combinations bond chemically. ABS bonds with most TPE grades; PP bonds with PP-based TPEs; PC bonds with certain TPU formulations.

We verify material compatibility for every new substrate-overmold pairing before tooling is committed — because discovering an incompatibility after tooling is built is an expensive lesson.

Two-Shot vs. Overmolding

Overmolding molds the substrate in one operation, then transfers it to a second mold for the overmold shot. Two-shot molding performs both operations in a single machine with no transfer.

We offer both processes and recommend the right approach based on your program’s volume, registration requirements, and tooling investment profile.

Why Choose Texas Injection Molding?

A trusted manufacturing partner for OEMs seeking precision, reliability, and US-based production.

Material Compatibility Expertise

We validate substrate and overmold material pairings for bond strength before tooling is committed — not after delamination is discovered in production.

In-House Tooling

Both the substrate mold and the overmold tool are built and maintained in our tool shop. No outsourcing, no coordination delays between suppliers.

Full Program Management

We manage the complete overmolding program — substrate molding, material selection, overmold tooling, production, and quality documentation.

Wide Material Range

ABS, PC, nylon, and PP substrates with TPE and TPU overmolds — we have experience with the full range of substrate and overmold material combinations.

One Part. Two Materials. No Assembly.

Overmolding eliminates the assembly operations, adhesives, and delamination risk of bonding two materials together after molding. When the design is right and the materials are compatible, an overmolded part is stronger, cleaner, and more reliable than any assembled alternative.

Texas Injection Molding manages the complete overmolding program — from material compatibility validation through substrate tooling, overmold tooling, production qualification, and ongoing manufacturing — in a single facility with a single point of contact.

Start Your Project Today

Contact the Texas Injection Molding team to discuss your program. We will review your parts,
recommend materials, and provide a quote — typically within 48 hours.