a Leader in Custom Injection Molding

SeaGate Plastics' 26,000 sq. foot injection molding facility located in Addison, Michigan specializes in injection molding and related processes. Our machine capabilities range from 35 to 650 tons of clamp force. Processes such as insert molding and standard injection molding are available to meet your specialized molding needs. We can produce custom products in addition to our standard product line.

At SeaGate Plastics we utilize the newest technologies at our plastic injection molding facility. We utilize robotic parts handling and material reclaim process for more environmentally friendly processing.

Our insert molding capability encapsulates metal or different plastic materials and other substrates in Thermoplastic to create more complex designs that combine rigid and flexible materials and can eliminate assembly and fasteners.

If you need a prototype on sample tooling, we can do that for you. We are able to make prototype parts quickly and cost effective for you. We also have established relationships with numerous experienced tooling sources which allow us to be more effective in making your parts correctly and on time.

What SeaGate Plastics can do for you?

  • Assist with proper material selection
  • Design considerations for you plastic parts
  • Effective manufacturing ideas
  • Assemble your plastic parts
  • Customized packaging of your plastic parts
  • Printing
  • Application of tapes

SeaGate Plastics capabilities:

  • Numerous single and multi head CNC routers with 3 and 5 axis capability
  • Advanced 5-axis routing and machining services to exact customer specifications
  • Advanced CAD/CAM and solid modeling supported design development and engineering
  • Cost effective prototyping and flexible production capabilities
  • Low and High volume production capability
  • CNC router cutting of parts up to 60” x 120” x 3 ½” thick
  • Computerized production saw cutting capability up to 102”
  • Die cutting
  • Screen printing capability up to 18x48”
  • Milling plastic parts
  • Drilling plastic parts
  • Tapping plastic parts
  • Plane plastics parts
  • Assembly
    • Adhesive bonding of plastics
    • Ultrasonic plastic welding
    • Thermal welding
    • Mechanical fastening

Common machined and fabricated plastic materials include:

  • ABS (Acrylonitrile Butadiene Styrene)
  • Acrylic
  • Foamed PVC
  • HDPE (Virgin & Recycled)
  • HIPS (High Impact Polystyrene)
  • Nylon
  • PC (Polycarbonate)
  • Plastic lumber
  • PP (Polypropylene)
  • PVC (Polyvinyl Chloride)
  • Plastic Electrically Conductive/Static Dissipative
  • UHMW (Ultra High Molecular Weight)

ex. Injection Molded Dunnage


ex. Urethane Rollers


ex. Thermoplastic Rubber (TPR) Glass Dunnage


ex. Thermoplastic Rubber (TPR) Glass Dunnage


ex. Point of Purchase display Hooks