Insert Molding Service

Get custom plastic parts molded with metal inserts. Upload a part to get an online quote.

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Insert Molding Service

Our insert molding processes produce custom prototypes and on-demand production parts in as fast as 15 days. We use aluminum molds that offer cost-efficient tooling, producing parts from a range of thermoplastic and liquid silicone rubber materials.

Low-volume production parts
Bridge tooling
Pilot runs
Functional prototyping and testing

Insert Molding Capabilities

Our basic guidelines for insert molding include important design considerations to help improve part manufacturability, enhance cosmetic appearance, and reduce overall production time.

Specifications

Maximum Part Size
US
18.9 in. x 29.6 in. x 8 in.
Metric
480mm x 751.8mm x 203.2mm
Volume
US
59 cu. in.
Metric
966,837 cu. mm
Depth
US
4 in. from parting line
Metric
101mm from parting line
Up to 8 in. (203.2mm) if the parting line can pass through middle of part
Projected Mold Area
US
Plastic: 175 sq in.
Silicone: 48 sq. in.
Metric
Plastic: 112,903 sq. mm
Silicone: 30,958 sq. mm

Tolerances

Minimum Volume
0.025 cu. in.
40.98 cu. mm
Machining Tolerance
±0.003 in. (0.08mm)
With substrate molds
Resin Tolerance
Thermoplastic: 0.002 in./in. (0.002mm/mm)
LSR: 0.025 in./in. (0.025mm/mm)

Insert Molding Process

Instead of a mold that produces a final part using two separate shots like overmolding, insert molding consists of a preformed part—often metal—that is loaded into a mold, where it is then overmolded with plastic.

Threaded Inserts

Reinforce mechanical properties for fastening, especially over repeated assembly

Bushings and Sleeves

Increase part durability for mating components that need more abrasion resistance

Metal Components

Integrate metal components for improved strength and functionality

Available Materials

We offer a wide range of materials for insert molding:

Thermoplastics

Engineering GradeHigh PerformanceCommodity Grade

Metal Inserts

BrassSteelStainless SteelAluminum

Quality Assurance

Design Analysis

Complete DFM review before production

Insert Placement Verification

Precise positioning and alignment check

Dimensional Inspection

Critical dimension verification

Pull-out Testing

Insert retention strength validation

Common Applications

Automotive

  • Electrical connectors
  • Mounting brackets
  • Control modules
  • Interior components

Electronics

  • Circuit board mounts
  • Housings
  • Connectors
  • Heat sinks

Medical

  • Device housings
  • Surgical instruments
  • Equipment mounts
  • Connectors

Industrial

  • Machine components
  • Structural parts
  • Equipment housings
  • Assembly fixtures

Design Resources

Beginner's Guide to Injection Molding

Learn what product designers must consider when designing a part for injection molding

Threaded Inserts Guide

Detailed information about our stocked threaded inserts

Material Selection Guide

Technical overview of thermoplastic resins

Start Your Insert Molding Project

Contact our expert team for free quotation and professional technical consultation. We look forward to helping you create excellent products.

Partsproto

Professional CNC machining and custom parts manufacturing services, meeting your precision machining needs with rapid delivery of high-quality components.

Contact Us

  • Email: [email protected]
  • Address: 11 Longjiangyi Rd, Dong Guan Shi, Guangdong Province, China, 523690

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