Insert Molding Service
with Mastars
Get custom plastic parts with metal inserts: upload your part for a quick online quote.
Insert Molding Service
Insert molding places a pre‑formed insert—commonly metal, but also ceramic or another plastic—into the mold cavity, then injects molten plastic to encapsulate it in a single step. This integrates multiple materials, enhances functionality, and reduces or eliminates secondary assembly. Typical inserts include threaded metal inserts for durable fastening and alignment. Cooling forms a solid, reliable part with the insert securely locked in place.
Metal inserts such as aluminum or stainless steel add tensile strength and conductivity, while plastic encapsulation improves wear resistance and structural integrity versus mechanical assembly. The process also supports size and weight reduction and is suitable for high‑volume production with consistent quality. RapidDirect offers insert molding services that achieve a strong, permanent bond between inserts and molded plastic for durable, high‑performance components.
Products of Mastars Insert Molding Services
Custom Insert Molding With Mastars
Mastars offers insert mold services as part of its injection molding capabilities. For a free insert molding design review and quote, upload your CAD files. Our expert team of injection molders will get back to you within 24 hours.
Your Can Gain:
✔️ Eliminate secondary assembly: Insert molded components are produced in a single process, removing the need for post-production assembly.
✔️ Cut overall production costs: Though insert molding has a slightly higher base cost than standard injection molding, expenses are offset by the elimination of post-assembly work.
✔️ Minimize part size and weight: Plastic parts with metal inserts are significantly lighter than all-metal alternatives, enabling more compact designs.
✔️ Boost component reliability: Precision metal inserts ensure consistent thread functionality and reduce wear and tear over the part’s service life.
✔️ Enhance structural strength: The one-shot insert molding process creates stronger parts than overmolding and other fabrication methods.
Insert Molding Design Guidelines
We don't have MOQ, only 1pcs is according to high standard to make, we pursuit the product is perfect to every customer, from 1pcs to million,we are glad to witness and grow together with our customers, that make us proud.
Our overmolding & insert molding guidelines cover key design considerations to boost part manufacturability, elevate aesthetics, and shorten production timelines.
| US | Metric | |
| Maximum Part Size | 18.9 in. x 29.6 in. x 8 in. | 480mm x 751.8mm x 203.2mm |
| Volume | 59 cu. in. | 966,837 cu. mm |
| Depth | 4 in. from parting line | 101mm from parting line |
| Depth | up to 8 in. if the parting line can pass through middle of part | Up to 203.2mm if the parting line can pass through middle of part |
| Projected Mold Area | 175 sq in. (plastic) | 112,903 sq. mm (plastic) |
| Projected Mold Area | 48 sq. in. (silicone rubber) | 30,958 sq. mm (silicone rubber) |
Materials for Insert Molding
✔️ ABS ✔️PC ✔️PMMA (Acrylic)
✔️ POM ✔️ PA (Nylon) ✔️ PE
✔️ PEEK ✔️ PP ✔️ HDPE
✔️ HIPS ✔️ LDPE
Applications for Insert Molding
✔️ End-Use Functional Parts
Insertion molding creates fully dense, smooth parts with superior mechanical performance
✔️ Scaled Production
Insert injection molding is best known for its unmatched production capabilities from thousands to millions of identical parts.
✔️ Certified Components
We offer ISO 9001, ISO 13485, IATF16949 & Medical - Class Products
Insert Molding Process Advantages
✔️ Durability: Metal inserts will guarantee the function of threads and mitigate wear and tear over the part’s life.
✔️ Strength: Because it’s a “one-shot” process, insert molding can produce stronger parts than overmolding and other processes.
✔️ Creating Production Parts: Insert molding is great for creating prototypes and production parts.
Endless Options
Choose from millions of possible combinations of materials, finishes, tolerances, markings, and certifications for your order.
Easy to Use
Get your parts delivered right to your door without the hassle of sourcing, project management, logistics, or shipping.
Vetted Network
We are ISO 9001, ISO 13485, and IATF 16949 certified. Only the top shops that apply to become Suppliers make it through our qualification process.
Our Ideas Have Helped Clients Bring Hundreds Of Products To Market
Certificates
Choose Mastars, You'll Gain
We don't have MOQ, only 1pcs is according to high standard to make, we pursuit the product is perfect to every customer, from 1pcs to million,we are glad to witness and grow together with our customers, that make us proud.
Download Our Manufacturing Equipments List
We offer a one-stop processing service from prototypes and molds to machining and assembly, and are equipped with various models of processing equipments from major domestic and international companies, for CNC machining, injection molding, mold making, and sheet metal manufacturing. Download Now！
Our Production Capability
✔️ More than 30 injection molding machines of various models
✔️ 2000T Sets injection machines from 30T to 2000T
✔️ 24H 3*8h shifts Uninterrupted production
✔️ Injection parts precision 0.01mm
Our Services
We don't have MOQ, only 1pcs is according to high standard to make, we pursuit the product is perfect to every customer, from 1pcs to million,we are glad to witness and grow together with our customers, that make us proud.
Industries We Serve
We don't have MOQ, only 1pcs is according to high standard to make, we pursuit the product is perfect to every customer, from 1pcs to million,we are glad to witness and grow together with our customers, that make us proud.
Our Partners
Quick links
Technical video
Stay Connected!
Manufacturing on Demand
Please fill in the following information to obtain plan details (information is confidential and not disclosed publicly), we will contact you within 24 hours, please keep your phone available!
Upload a 3D/2D model to see instant pricing, lead time, and DFM feedback.
