Over molding TPE/TPU onto metal or plastic inserts. Get a factory-direct quote within 24 hours.
15+ Years
Over molding experience
200+
Material pairings tested
±0.05 mm
Molded part tolerance
24 Hours
Quote turnaround on weekdays
The problem
Soft layers that peel, seals that leak, and surprise assembly costs. As a China over molding manufacturer, we solve all of them.
The grip or seal lifts away from the base. A weak bond is the number one reason over molded parts get returned.
A seal that does not close fully lets moisture reach the electronics and shortens product life.
Gluing or snapping parts together by hand adds labor, slows the line, and creates weak points.
Some plastics simply will not bond. A bad match means the layer falls off or melts the base part.
Uneven walls and poor process control leave visible defects right on the part your customer touches.
You get sent between vendors. One cannot mold the soft layer, the other cannot make the base.
Over molding is a two-step process: mold the rigid base first, then mold a soft layer directly over it. The two materials bond by heat, chemistry, or a mechanical lock.
What is over molding
Over molding joins a soft material to a hard one in the mold. First we mold the rigid base part, called the substrate. Then we mold a soft material such as TPE, TPU or silicone right over it. Heat, chemistry, or a mechanical lock holds the two together - so you skip glue and assembly.
Capabilities
From the base part to the soft layer, every step runs in-house at our China factory, so quality and lead time stay under our control.
Two materials or colors molded in one cycle on a dual-injection machine.
Metal inserts, threads and bushings encased in plastic in a single tool.
Three or more materials or colors layered into one seamless part.
Rubber-like TPE and TPU grips that feel good and stop slipping.
Molded-in gaskets and seals that keep water and dust out for good.
We test material pairs for adhesion before the mold is even cut.
Gating, bonding features and a free DFM report before cutting starts.
Low-volume bridge tools and hardened multi-cavity production molds.
Materials
The soft layer only sticks when the two materials match. These are the pairings we mold most, and we test new ones on request.
ABS+TPE
The classic soft-grip combo. Tool handles, appliance grips and consumer products.
ABS+TPU
Tougher and more abrasion resistant. Good for protective cases and buttons.
PC/ABS+TPE
Strong base with a soft feel. Electronics housings and wearable devices.
PC/ABS+TPU
Impact resistant and grippy. Power tool housings and phone cases.
PP+TPE
Chemical resistant. Toothbrush grips, personal care and seals.
PA (Nylon)+TPU
Oil and acid resistant. Automotive parts and cable connectors.
PBT+TPU
Dimensionally stable. Electrical connectors, sensors and clips.
Metal+TPE / Silicone
Metal inserts with a soft skin. Smartwatch bands, surgical tools, hybrid parts.
Design guide
A good over molded part is designed for bonding, not glued after the fact. These simple rules keep your soft layer locked on for good.
Rough beats glossy. A textured bonding area gives more surface for the soft layer to grip.
Leave at least 0.5 degrees of draft on the bonding wall so the part releases cleanly.
Small ribs or grooves give the two materials more area to bond and hold each other.
Sharp corners concentrate stress and split apart. Use a radius of 0.5 mm or more.
A mechanical undercut locks the soft layer in place and takes load off the bond.
Aim for 1.5 to 2.5 mm walls. Too thin short shots; too thick sinks and warps.
Stay between 0.6 mm and 8 mm. Thin layers bond well; thick layers cure unevenly.
Confirm the two materials bond before tooling. We test pairs for free during DFM.
Solutions
Whatever the job - a softer grip, a tighter seal, or a tougher skin - we have an over molding solution that fits.
Comfortable, non-slip grips molded straight onto tools and handles.
Molded-in gaskets and seals that keep water, dust and air out.
Textured soft areas exactly where hands and feet need traction.
A tough outer layer that shields parts from impact, heat and wear.
Flexible over molded ends that stop cables from breaking at the joint.
Two colors in one part for a clean look with no painting or printing.
Metal inserts wrapped in plastic for strong, light, functional parts.
Soft, skin-safe layers for surgical tools and wearable devices.
Industries
As a China over molding supplier and manufacturer, our company delivers soft-touch and sealed parts to customers in many demanding sectors worldwide.
Ergonomic grips, anti-vibration handles and durable trigger switches.
Surgical tool grips, device housings and comfortable wearables.
Shift knobs, weather-resistant switches and interior soft-touch trim.
Waterproof casings, soft buttons and ergonomic device handles.
Battery seals, charging handle grips and protective connectors.
Machine grips, insulated handles and vibration-damping mounts.
Insulated cable glands, protective covers and handle grips.
Cable strain relief, weatherproof seals and soft-touch keypads.
Why choose us
We are a one-stop over molding supplier: base part, soft layer, tooling and support all in one accountable partner.
Buy straight from the manufacturer. No middleman, no markup, no surprise fees.
We prove the bond between your two materials before the mold is cut.
Design, machining, EDM and polishing under one roof for full control.
Under 0.02 mm alignment between base and overmold for a clean seam.
In-process checks plus CMM reports and first-article inspection on every part.
ISO 9001 quality system with IATF 16949 and ISO 13485 experience.
A single contact owns your order from quote to delivery, so nothing gets lost.
Your designs stay yours. We sign NDAs and keep files fully confidential.
How it works
A simple, transparent process designed to remove the guesswork from over molding.
Send STEP, STP, IGES or PDF drawings. Tell us both materials you have in mind.
Free DFM feedback, a material pairing check and a clear factory-direct price.
We cut the tool, mold the base and the soft layer, and send samples with a report.
Global shipping with tracking, mold data pack and ongoing production support.
Which process fits you?
These four multi-material processes look similar but solve different problems. As your over molding supplier, we help you pick the right one.
FAQ
Answers to the questions buyers ask us most about over molding in China.
Send your files and get a factory-direct quote, a free material pairing check and a clear lead time within 24 hours.