Overmolding

Overmolding Services in Canada

Overmolding bonds a second material onto a first in a controlled molding process — typically a softer elastomer (TPE, TPU, silicone) molded over a rigid plastic substrate. The result is a single integrated part with multiple functional zones: a hard structural core with a soft grip, a metal threaded insert with a sealed plastic body, or a co-molded gasket integrated into a housing. Canadian overmolding capacity supports consumer products, medical devices, automotive components, and industrial tooling.

Canadian supplier network ISO 9001:2015 Vetted suppliers

Overmolding in Canada

Overmolding is what makes modern consumer products feel premium. A toothbrush handle’s soft grip, a power tool’s rubberized housing, a medical device’s gasket — these are all overmolded parts where a softer, grippier, sealing material has been molded directly onto a rigid plastic core. Canadian overmolding capacity is concentrated in Ontario and Quebec, with strong support from the automotive and consumer products industries.

Where Overmolding Wins

Soft-touch grips and ergonomic surfaces. Power tools, kitchen utensils, electronics housings, and sporting goods all use overmolded TPE or TPU for tactile quality.

Integrated seals and gaskets. Co-molded silicone or TPV gaskets eliminate assembly steps and ensure consistent seal placement.

Multi-material consumer products. Toothbrushes, razors, kitchen appliances, and personal care items where soft and rigid zones improve function and feel.

Medical device housings. Soft-touch handles on surgical instruments, sealed enclosures for electronic medical devices, biocompatible silicone overmolds on PEEK or rigid plastic substrates.

Two-Shot vs. Insert Overmolding

MethodVolumeTooling CostConsistency
Two-shot (2K)High volumeHighExcellent
Insert overmoldingLow-mediumModerateGood

For high-volume consumer products, two-shot tooling pays back in cycle-time and yield. For low-to-medium volumes, insert overmolding lowers the up-front investment.

Canadian Overmolding Network

Our Canadian overmolding network includes shops with two-shot machines for high-volume consumer products, insert-overmolding cells for medium-volume industrial work, and ISO 13485-certified medical molders for biocompatible silicone-on-PEEK and similar applications.

Specifications

Overmolding at a Glance

Certifications
  • ISO 9001:2015
  • ISO 13485 (Medical)
  • IATF 16949 (Automotive)
  • FDA Compliant Materials
  • USP Class VI
Tolerances
Standard
+/- 0.1 mm
Precision
+/- 0.05 mm
Lead Times
Prototype
4–8 weeks (with tooling)
Production
2–4 weeks (after tooling)
Network
Closed Beta

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Available Materials

TPE / TPV / TPU (Soft Overmolding) Liquid Silicone Rubber (LSR) Polypropylene / Polyethylene (Rigid Substrate) ABS / PC (Rigid Substrate) Nylon (Rigid Substrate) PEEK (Medical/Industrial)

Industries We Serve

Consumer Products
Medical Devices
Automotive
Industrial Tools
Personal Care
Sporting Goods

Frequently Asked Questions

What's the difference between overmolding and two-shot molding?
Two-shot (2K) molding produces both materials in a single press in one cycle — the substrate molds, the tool rotates or indexes, and the second material molds over it. Overmolding (insert overmolding) typically means molding the substrate first as a discrete part, then loading it into a second mold for the overmold cycle. Two-shot is faster and more consistent at high volume; insert overmolding has more flexibility for low-to-medium volumes. We route based on volume and complexity.
How do I know which materials will bond?
Bonding depends on chemical compatibility, temperature, and surface preparation. TPEs designed to bond to specific substrates (PP, PC, ABS, nylon) are well-documented from major resin suppliers. For non-bonding combinations, mechanical interlocks (undercuts, holes, ribs) hold the materials together. We work through bond-vs-mechanical decisions during the DFM review.
Can metal inserts be overmolded into plastic parts?
Yes — this is a common variant called insert molding (see [insert molding](/manufacturing/injection-molding/insert-molding/)). Metal threaded inserts, electrical contacts, or structural reinforcements are loaded into the mold, plastic injects around them, and the finished part has fully integrated metal-and-plastic functionality.
What's a typical tooling cost for overmolding?
Two-shot tooling is typically 1.5–2.5x the cost of a single-shot tool because the tool either has rotating cores or two cavities running in sync. Insert overmolding requires two separate tools but each is closer to single-shot pricing. Total tooling cost for a moderate-complexity overmolded part typically ranges from CAD $25,000 to $80,000.

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