Custom Insert Molding Services for Precision OEM Plastic Components

We provide high-precision insert molding solutions for metal, brass, threaded, and electronic inserts, supporting complex OEM plastic part manufacturing for automotive, electronics, medical, and industrial applications.

insert molding services manufacturer

ISO 9001 Certified
NDA Protection
Fast Quote Response
Flexible MOQ
Free DFM Review

Custom Insert Molded Parts

Common Insert Molding Challenges We Help Solve

Insert Positioning Accuracy

Precise fixture and mold design ensure accurate insert placement and repeatable alignment during molding.

Plastic Flash Around Inserts

Optimized shut-off design minimizes resin leakage and flash around embedded components.

Weak Insert Bonding

Material compatibility and mechanical locking structures improve bonding strength between insert and resin.

Insert Shift During Injection

Dedicated tooling and robotic loading reduce insert displacement caused by injection pressure.

Cracking Around Embedded Metal

Controlled wall thickness and stress-relief geometry prevent cracking after cooling.

Our Insert Molding Manufacturing Capabilities

Item Capability
Part Size 5mm–500mm
Tolerance ±0.02mm
Mold Lead Time 15–25 Days
MOQ 100 pcs
Insert Types Brass / Steel / Aluminum / Copper / PCB
Resin Materials ABS / PC / PA / PBT / PEEK / PPS
Machine Range 50T–500T
Secondary Ops Assembly / Ultrasonic / Printing

Engineering Considerations for High-Quality Insert Molded Parts

Insert Retention Design

Knurling, undercuts, and grooves improve mechanical locking strength between insert and molded plastic. This ensures the embedded component will not loosen or pull out during part usage, even under heavy mechanical stress.

Thermal Expansion Compensation

Different thermal expansion rates between plastic and metal inserts must be considered to prevent cracking. We carefully match material pairs and design proper wall thickness to absorb thermal stress during temperature changes.

Gate Position Optimization

Proper gate placement minimizes insert shift and ensures balanced resin flow. Our engineering team simulates flow patterns to place gates away from critical insert areas, preventing pressure-induced displacement.

Cooling Balance Design

Uniform cooling prevents warpage and dimensional instability around insert areas. We design customized cooling lines to ensure consistent cooling rates across the entire part, especially around the heavier metal insert regions.

Mold Venting Around Inserts

Additional venting avoids trapped gas near insert interfaces. Proper venting ensures complete resin filling without burn marks or short shots, resulting in strong bonding between the insert and plastic material.

Insert Materials and Resin Options

Insert Materials

Material Common Use
Brass Threaded Fastening
Stainless Steel Structural Reinforcement
Copper Electrical Conductivity
Aluminum Lightweight Components
PCB/Electronics Smart Devices

Plastic Resin Materials

Material Best Application
ABS Consumer Products
Nylon PA66 Mechanical Strength
PC Impact Resistance
PBT Electrical Components
PEEK High Temp Medical/Industrial

Applications of Insert Molded Components

Automotive

Sensor Housings, Connector Bodies

Medical Devices

Device Components, Surgical Tools

Electronics

Connector Bodies, PCB Encapsulation

Industrial

Switch Housings, Valve Components

Fasteners

Threaded Plastic Fasteners

Consumer Appliances

Appliance Components, Handles

Recent Insert Molding Projects

Automotive Insert Molding Parts

Automotive Brass Insert Housing

  • Material: PA66+GF30
  • Insert: Brass Threaded Insert
  • Tolerance: ±0.03mm
  • Annual Volume: 200,000 pcs

Medical Device PCB Housing

Medical Device PCB Housing

  • Material: Medical Grade PEEK
  • Insert: PCB & Copper Contacts
  • Tolerance: ±0.02mm
  • Annual Volume: 50,000 pcs

Smart Sensor Connector Body

Smart Sensor Connector Body

  • Material: PC/ABS Blend
  • Insert: Stainless Steel Pins
  • Tolerance: ±0.025mm
  • Annual Volume: 120,000 pcs

Frequently Asked Questions About Insert Molding

What is insert molding?

Insert molding is a manufacturing process where pre-fabricated components (inserts, typically metal) are placed into a mold cavity, then plastic resin is injected around them to form a single integrated part. This combines the strength of metal with the flexibility of plastic.

What materials can be used in insert molding?

We work with a wide range of insert materials including brass, stainless steel, copper, aluminum, and even PCB/electronic components. For the plastic resin, we support ABS, Nylon, PC, PBT, PEEK, PPS, and many other engineering plastics.

How do you prevent insert movement during molding?

We use precision fixtures to hold inserts firmly in place during injection, along with optimized gate positioning to reduce pressure impact on inserts. We also use robotic loading for consistent placement, and flow simulation to ensure balanced resin flow that won’t shift inserts.

What tolerances can you achieve?

Our precision insert molding process can achieve tolerances as tight as ±0.02mm for critical dimensions, depending on part size and material requirements. We use CMM inspection to verify all critical dimensions to ensure compliance with your specifications.

Can you mold threaded brass inserts?

Yes, threaded brass inserts are one of our most common insert types. We specialize in embedding threaded inserts to create strong, reliable threaded connections in plastic parts, eliminating the need for post-mold insertion and reducing assembly costs.

Do you offer low-volume prototype insert molding?

Absolutely. We support low-volume prototype insert molding to help you test your design before full production. We offer flexible MOQ starting from 100 pcs, with fast prototype lead times to help you accelerate your product development cycle.

What files do you need for quotation?

To provide an accurate quote, we typically need your 3D CAD files (STEP, IGES, or STL format), 2D drawings with critical dimensions and tolerances, material requirements, and expected annual volume. You can upload your files directly through our quote form to get started.

Ready to Start Your Insert Molding Project?

Upload your CAD file now to get an instant quote and free DFM review within 12 hours.

Please be sure to describe the specific customization requirements in detail. Otherwise, we will ignore the submitted content.

Quality Assurance

FAI / IQC / IPQC / OQC / CMM Inspection

Lead Time

Prototype: 7-10 Days | Tooling:15-25 Days | Mass Production: 15-30 Days

Confidentiality

Strict NDA Protection for All Customer Projects

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