About Mold Design and Tooling

At Seaway Plastics, we can quickly build aluminum molds, aluminum-and-steel combinations, or hardened steel molds ranging from Class 105 to Class 101, all in the United States.  Our highly qualified designers, engineers, and tool makers can guide customers to the optimal materials based on:

  • Resin desired for the product
  • Number of anticipated shots
  • The expected life of the mold
  • Production, prototype & Bridge Molds
  • Other project specifications
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Large & Multi-Part Projects

Our professional engineering and production teams can handle large, multi-part projects, and our equipment and facilities are designed to meet the most demanding needs of almost any project.

Fast & Flexible

Seaway’s in-house tool rooms in Florida and Minnesota offer the capability for fast and flexible mold making. Our mold designers and CNC programmers use the most advanced software to meet the tooling needs of our customers.


  • 20 CNC machines including 5-axis machines
  • 6 Electronic Discharge machines (EDM both wire & sinker)
  • Makino wire CNC
  • Makino sinker CNC
  • 10-ton crane
  • Single to high cavitation
  • Upfront DFM 
  • Mold Flow and design support

Service Molds

Following the initial production runs required for new products, used high-volume molds are often repurposed for low-volume runs to make service and repair parts.

We are experts at evaluating your current molds to determine whether they are worth the investment of moving and repairing them for low volume production. We can support your mold use strategy in a number of areas including:

  • Low-volume transfers
  • End-of-life production
  • Transfer previously high-volume tooling for low-volume applications


We also help with reshoring. When offshore production becomes less profitable due to shipping costs, quality concerns, or intellectual property issues, we can gather the tools and arrange to have them back in the United States and producing new parts in just weeks.

When you’re ready to reshore, let us know how we can help you bring jobs back to the USA. Or contact us about your other mold transfer needs.

New Tooling Projects

Part of the Seaway Advantage is our in-house tool shop. At each Seaway location, tooling and process engineers will collaborate directly with your team to ensure a smooth development phase that hits deadlines and stays within budget.

Mold Design

Featured Case Study

Featured Case Study

Mold Design and Tooling

Looking to extend their innovation in the surgical realm, this medical device company devised a new surgical arm to assist in different operations. Having so many moving parts that needed to meet different requirements, many manufacturers would have had to outsource for some parts. This then increased not only the complexity of the supply chain but also time spent per part. That’s where Seaway’s mold design and tooling comes in.

Existing Mold Transfers

When injection molding businesses move, close down, downscale, or merge with other entities, they often have nowhere to house their molds, and they have to transfer their molds/tools to another molder. This requires them to search for plastic injection molders, and go through the process of relocating the tools and the entire manufacturing process to another factory.

Seaway Plastics has rehoused hundreds of tools. We store tools in our climate-controlled warehouses, and when they arrive, we carefully examine them to find and address any faults, blemishes, or irregularities. We also assist with mold-moving logistics and tool transfers.

Existing Mold Transfers


An Outstanding Commitment to Quality

Ready to Discuss Your Injection Molding Project?