Post Molding Production and Services

About Post Molding Production

Most molders don’t offer post-production processes or secondary services. Instead, they just “shoot and ship” — They shoot plastic into the mold, cut it, and ship it to the customer. Then, the customer has to complete the assembly or handle other post-production processes. This increases costs and leads to long wait times.

Seaway Plastics Engineering and Wright Engineered Plastics offer full turnkey services and complete assemblies. Our post-production and secondary services include:

  • Sonic welding
  • Heat staking
  • Thermal and ultrasonic inserting
  • Post molding machining and CNC machining
  • Ultrasonic cleaning
  • Laser marking
  • Full painting capabilities
  • EMI/RFI shielding
  • Screen printing
  • Pad printing
  • Light assembly

Most of our processes meet NADCAP accreditation standards for 7004 and 7108, and our complete in-house operations and wide range of post-molding services allow our customers to take care of their whole project in one place.

Let the Seaway family handle your entire project from start to finish! Contact us today to talk about your project.

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Top Coat Painting & Shielding

Top Coat Painting & Shielding

Some projects rely on over-molding or in-mold design and decoration (IMDD) to add finishing touches, but these methods are not always an option due to color variations, material textures, security needs, part size, or other challenges. In these situations, customers should consider top coat painting or shielding.

Top coat painting and shielding add finishing touches to parts through film, paint, powdered plastics, or metallic vapors. These processes add aesthetic appeal, while also improving functionality and longevity.

Top Coat Painting

Top Coat Painting

Seaway Plastics and Wright Engineered Plastics offer the following injection molding painting processes:

  • Spray painting
  • Powder coating
  • Stamping/pad printing
  • In-mold painting

Each of these processes offers unique benefits, and the right option depends on the needs of the project. Many customers, for example, opt for spray painting because it is the simplest and most cost-effective option. Others opt for in-mold painting because they want adhesive properties that can outlast inclement weather, and this process reduces the risk of chipping or flaking by embedding plaint into the plastic material during the molding process.



Shielding prevents electronics from emitting certain electrical currents and increases device security and integrity. Without shielding, static would constantly disrupt phone calls and video streaming, and before this technique became popular, electromagnetic interference (EMIs) and radio frequency interference (RFIs) were much more prominent.

Molders use different shielding techniques to make plastics conductive, and they include electroless plating and electrolytic plating. With electroless plating, operators deposit a thin metal coating with a thickness of 1 micrometer to 12.5 micrometers onto parts.

Electrolytic plating, in contrast, ranges between  5 micrometers and 75 micrometers. This is not much more than the diameter of a strand of human hair, but it offers more protection than electroless plating.

Resins respond to shielding differently, and while some are very hospitable to the process, others may require a blend to work with shielding. The most receptive resins to shielding are:

  • Acrylonitrile Butadiene Styrene (ABS)
  • Nylon
  • PC/ABS Blend
  • PC/PBT
  • Poly Aryl Amide
  • Polybutylene Terephthalate (PBT)
  • Polycarbonate (PC)
  • Polyether Imide (PEI)
  • Polyphenylene Oxide (PPO)
  • Polyphthalamide (PPA)
  • Polyphthalamide (PPA)
  • Polystyrene (PS)

These resins are not as receptive to shielding:

  • Liquid Crystal Polymer
  • PEEK
  • Polyethylene
  • Polyimide
  • Polypropylene
  • Teflon (PTFE)

If you want shielding but were planning to use a resin that is not receptive to the process, you should consult with an engineer from Seaway Plastics or Wright Engineering Plastics. They can help you make the best decision for your project.

Our painting and shielding processes can help maximize the look and function of your parts. Contact us today to talk about your project and request a quote.

Featured Case Study About Post Molding Production

The company needed 10 new parts made for a new sensor used now for filtration systems for oil field workers. Through their initial planning, they understood that they needed a few different requirements met. The first was that they needed to produce these parts with a manufacturer that had high QA and QC standards and had stringent testing abilities to mimic real-world situations. The second was that they needed a specific plastic resin that would withstand extreme exposure to moisture, particles, and chemicals. The third was that they required a manufacturer with experience in producing parts made with this specific resin. Due to its highly engineered nature, creation of these parts required specialized attention and testing.


An Outstanding Commitment to Quality

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