About Overmolding
Overmolding is a unique injection molding process that results in a seamless combination of multiple materials into a single part or product. It typically includes a rigid, plastic-base component overlaid with a thin, pliable, rubber-like thermoplastic elastomer (TPE) exterior layer or other materials using either a single-shot (insert molding) or two-shot (multiple-shot molding) technique.
Advantages of Overmolding
Increasingly popular with manufacturers, you may find overmolding to be an excellent option for your next project when you consider the significant advantages it provides.
- Better adhesion between components
- More compact design
- Lower labor costs during production
- Noise and vibration reduction
- Protection from UV and corrosive chemicals
- Waterproofing
- Electrical insulation
- Improvement of product viability and customer satisfaction.
Durability
It affords enhanced product design and manufacturing. The precision with which you can place inserts into a mold design cannot be achieved with other molding processes. In short, plastic parts with integrated components are much more robust and more reliable.
Light Weight
Plastic parts can be up to 50 percent lighter than their metal counterparts, which is one of the primary reasons many industries are turning to plastic molding for parts. From fuel efficiency to better ease-of-use for surgical instruments, lighter weight enhances performance and functionality.
Smaller in Size
The insert molding process allows the production of much smaller or thinner parts without sacrificing durability or performance. A simple example is vehicle components. Thinner door and console parts mean more room in the interior of the car.
Which material is suitable for your overmolding project?
Increasingly popular with manufacturers, you may find overmolding to be an excellent option for your next project when you consider the significant advantages it provides.
- Better adhesion between components
- More compact design
- Lower labor costs during production
- Noise and vibration reduction
- Protection from UV and corrosive chemicals
- Waterproofing
- Electrical insulation
- Improvement of product viability and customer satisfaction.
Plastic Over Plastic
At first, a rigid plastic substrate is molded, then another rigid plastic is molded onto or around the substrate. The plastics could differ in color and resin.
Rubber Over Plastic
At first, a rigid plastic substrate is molded, then a soft rubber or TPE is molded onto or around the substrate. This is often used to give a soft grip area to a rigid part.
Plastic Over Metal
At first, a metal substrate is machined, cast or formed, then the substrate is inserted into an injection molding tool, and the plastic is molded onto or around the metal. This is often used to capture metal components in a plastic part.
Rubber Over Metal
At first, a metal substrate is machined, cast, or formed. Then the substrate is inserted into an injection molding tool, and the rubber or TPE is molded onto or around the metal. This is often used to provide a soft-grip surface.
Material options
Moxperts offer a wide variety of certified alloys for rapid overmolding services. If the material is not listed, feel free to contact us for a customized solution.
- Acetal polyoxymethylene (POM)
- Acrylonitrile butadiene styrene (ABS)
- Ethylene Propylene Diene Monomer Rubber (EPDM)
- Nylon 66 (PA66)
- Glass-filled, polyamide (PA-GF)
- High density polyethylene (HDPE)
- Low density polyethylene (LDPE)
- Liquid Crystal Polymer (LCP)
- Melt Processable Rubber (MPR)
- Polybutylene terephthalate (PBT)
- Polycarbonate (PC)
- Glass-filled polycarbonate (PC-GF)
- ABS polycarbonate (PC-ABS)
- Polyethylene terephthalate (PET)
- Polymethyl methacrylate (acrylic) (PMMA)
- Polyphenylene sulfide (PPS)
- Polypropylene (PP)
- Polyvinyl Chloride (PVC)
- Polystyrene (PS)
- Polystyrene +
- polyphenyl ethers (PS-PPE)
- Thermoplastic elastomer (TPE)
- Thermoplastic vulcanizates (TPV)
Prototype
Finishing Services
As molded
- Part number
- Logo
Standards for plastic injection molding surface finishes established by Society of Plastic Industry (SPI).
- Grade A: Glossy Injection Molding Surface Finish. Min. roughness: 0.012 μm. Mainly for Acrylic, PC.
- Grade B: Semi-Glossy Injection Molding Surface Finish. Min. roughness: 0.05 μm. Mainly for ABS, HDPE, Nylon, PP, Polystyrene.
- Grade C: Matte Injection Molding Surface Finish. Min. roughness: 0.35 μm. Mainly for ABS, HDPE, Nylon, PP, Polystyrene.
- Grade D: Textured Injection Molding Surface Finish. Min. roughness: 0.80 μm. Mainly for ABS, HDPE, Nylon, PP, Polystyrene, TPU.
