Overmolding and Insert Molding Service
What is Overmolding Service?
Overmolding service is a process of taking a substrate parts and then using injection molding to add additional layers over it, like thermoplastic or silicone rubber material. Traditionally, the substrate parts are plastic or metal with higher melting point, once that parts is cooled, the layer is injection molded over it. So the cycle time is a bit longer
Overmoulding Application Examples:
- Power tool handles
- Medical devices (enhanced grip)
- Consumer electronics (non-slip function)
What is Insert Molding Service?
Insert molding refers to pre-installing the insert in the mold and injecting resin. The molten resin is combined with the insert to melt. The insert is usually metal, and the injected plastic material is usually rigid plastic. During the molding process, the insert usually needs to be preheated so that its surface temperature is close to the melting point of the cover material for optimal bonding.
Insert Molding Application Examples:
- Electronic products (connectors)
- Automotive parts (engine fasteners)
- Medical devices (implant parts)
| Name | Detail |
|---|---|
| Size |
78.74in. x 59.05in. x 39.37in. 2000mm x 1500mm x 1000mm |
| Mold Cavities | Single or multi-cavity |
| Mold Life | Unlimited (We will open a new mold if the old one worn out) |
| Mold Storage | Forever |
| Mold Material | P20 Steel |
| General Tolerance | Normally +/- 0.008in.（0.2mm) |
Overmolding and Insert Molding Material
Overmolding General Material
A substrate is formed first, and then a second injection molding is performed to form a coating.
Common Materials:
- Substrate Material: ABS, PC, PA, PP, ABS/PC
- Coating Material: TPE, TPU, TPV, Silicone
Insert Molding General Material
Pre-inserted metal parts are encapsulated by injected plastic, then cooled and solidified into a single, durable component.
Common Materials:
- Metal inserts: steel, stainless steel, brass, aluminum
- Plastic: PA, ABS, PC, PP，PE
Overmolding Cost
- Requires additional mold design (two-step process)
- Requires more material (soft overmoulding)
- Suitable for high volume production, otherwise higher cost
Insert Molding Cost
- Metal inserts need to be purchased, but subsequent assembly can be reduced
- Suitable for automated production, reducing labor costs
Advantages of Overmolding
- Enhanced Grip & Comfort: Better grip and comfort for operators.
- Improved Durability: Boosts wear resistance and impact strength.
- Seamless Integration: Strong bonding and improved sealing.
- Aesthetic Functional Design: Soft-touch finish improves appearance.
- Vibration & Shock Absorption: Reduce vibration to extend service life.
Advantages of Insert Molding
- Stronger Bonding: Metal and plastic combined for higher mechanical strength.
- Reduced Assembly Time & Cost: Eliminates assembly, speeds production.
- Lightweight & Durable: Plastic reduces weight while keeping strength.
- Design Flexibility: Supports complex, precise multi-functional parts.
- Improved Reliability: Keeps metal inserts secure for stable performance.
Why Choose Jiangzhi As Your Overmolding Manufacturer？
Strong integration ability
Experienced engineering service
Quality is priority
Specialize in assembly
Logistics & fulfillment
FAQs of Overmoulding and Insert Molding
What is the difference between overmolding and insert molding?
Overmolding involves injecting two shots of materials to form the substrated and the overmold. Insert molding only involves injecting one shot of molten plastic, though the metal insert needs to be purchased or created separately.
What is the difference between two-shot molding and overmolding?
Two-shot molding typically makes sense only for larger production runs, whereas overmolding is more suitable for low-volume production runs.
Is overmolding expensive?
Overmolded parts are made in two-step process. This increases part cycle time and is thus more expensive than molding a single part with no overmolding.
What is an example of insert molding?
Insert molding is often used to add a plastic layer on top of a metal one, for example, to add a plastic handle to a metal screwdriver. Jiangzhi can also use insert molding to manufacture insulated pipes, wiring, and other similar products, or embed electronics into plastics.
