Custom silicone overmolding onto rigid plastic substrates for products requiring soft-touch areas, sealing, grip, protection or integrated multi-material structures. We support structure review, substrate and silicone selection, tooling, sampling, interface confirmation and repeat OEM/ODM production.
WHEN IT FITS
Suitable for products that require flexible grip or improved surface feel on a rigid plastic body.
Suitable where silicone is used to protect edges, contact areas or exposed product surfaces.
Suitable where silicone is integrated into a plastic structure for sealing or controlled contact.
Suitable for housings and structural parts requiring both rigid plastic support and flexible silicone areas.
Suitable where silicone forms a functional feature such as grip, cushion, sealing edge or flexible interface.
Suitable for approved silicone + plastic structures requiring consistent repeat OEM/ODM production.
PROJECT INPUTS
The product structure should be reviewed before tooling to confirm geometry, interface, substrate material, silicone material and overmolding feasibility.
Sketches or 2D drawings with the plastic structure and silicone areas.
CAD files of the substrate and overmold geometry.
An existing part used as the structure and interface reference.
The plastic part or housing that will be overmolded.
Where silicone should cover, seal or grip.
Substrate and silicone expectations reviewed together.
Key dimensions and tolerance stack-up across materials.
Sealing, grip, protection or contact function defined per use.
How the overmolded part fits the final assembly.
Market context reviewed for material and finish requirements.
MATERIAL COMPATIBILITY
Material compatibility is reviewed according to substrate type, silicone grade, interface design, bonding method and project function. Not every plastic and silicone combination will bond directly. Depending on the project, mechanical retention, surface treatment, primer or other bonding approaches may be required.
Common substrate for grip and protective overmolding.
Used where stiffness and clarity are required.
Reviewed for bonding or mechanical retention.
Higher-strength substrates reviewed for interface design.
Reviewed per substrate and application.
Silicone or LSR grade selected for the substrate and function.
INTERFACE & BONDING
The interface between plastic and silicone should be reviewed before mold development to reduce separation, leakage, flash and fit issues.
Bonding area defined and sized for the required retention.
Holes, grooves or through-features planned where direct bonding is not suitable.
Shut-off areas defined to control silicone flow and flash.
Locking features planned for mechanical retention.
Contact surfaces reviewed for feel and function.
Overmold thickness balanced for coverage and cure.
Transition between rigid and flexible areas defined.
How the part fits the final assembly reviewed.
DESIGN BEFORE TOOLING
Substrate geometry reviewed for overmolding.
Overmold shapes and coverage planned.
Draft angles planned for clean demolding.
Parting line placement agreed before tooling.
Shut-off area defined to control flow and flash.
Flash allowance and trimming reviewed per surface.
Wall sections planned for both materials.
Tolerance stack-up across plastic and silicone reviewed.
Substrate positioned and supported in the mold.
Demolding sequence reviewed before tooling.
TOOLING & SAMPLING
Each step is confirmed per project. Dedicated tooling and sampling support is described on the Tooling & Sampling capability page.
The drawing and plastic structure are reviewed for overmolding.
Substrate, silicone and interface approach are reviewed.
Mold structure, shut-off and positioning are reviewed.
Overmolding tooling is built around the confirmed design.
First samples are molded with the actual substrate.
Bonding or retention and fit are reviewed on samples.
Samples are checked for dimensions and function.
The approved sample becomes the production reference.
PRODUCTION
Production follows the approved sample and confirmed material, interface and project specifications.
Substrates are prepared per the agreed bonding approach.
Substrates are positioned and supported in the mold.
Silicone is overmolded per the agreed parameters.
Parts are cured to the confirmed state before handling.
Parts are removed and handled per the agreed method.
Flash is trimmed and surfaces finished per the agreed criteria.
Parts are checked against the approved sample.
Multi-part products assembled per project scope.
Parts packed per the agreed specification.
QUALITY FOCUS
Checks are aligned with the approved sample and agreed criteria — see the Quality Control capability.
Bonding or mechanical retention reviewed on samples.
Coverage matches the confirmed overmold geometry.
Flash kept within the agreed allowance.
Shut-off areas clean per the agreed criteria.
Dimensions checked against the approved drawing.
Overmold thickness matches the confirmed design.
Surface quality consistent across batches.
Substrate positioned and retained as designed.
Parts assemble into the product as intended.
Repeat orders produced against the approved sample.
APPLICATION DIRECTIONS
Typical directions where silicone + plastic overmolding is applied.
Rigid housings with flexible silicone areas.
Grip and protective overmolding for travel products.
Overmolded components around devices and connectors.
Soft-touch components for beauty and personal care.
Protective structures combining rigid and flexible areas.
Multi-material products developed for brand programs.
RELATED CAPABILITIES
Related manufacturing capabilities across the ESKY workflow.
Compression and transfer molding for silicone products and components.
Liquid silicone rubber molding for detailed geometry and repeat production.
Silicone molded around metal inserts and hardware.
Dedicated tooling and sampling built around the confirmed design.
Product development combining silicone with plastic, metal and other components.
Checks against the approved sample across production.
FAQS
SEND YOUR RFQ
Share your drawing, CAD file, plastic substrate details or reference sample. Tell us about the silicone areas, interface requirements and estimated quantities.
PROJECT INTAKE
Share your substrate details and drawings so we can review materials, interface, tooling and bonding.