The technology behind thermoforming can be confusing, which is why we're offering you an inside look at how we develop a part through this process.

Technology MoldStep One: Building a Prototype Mold

We typically begin with a prototype mold. Prototype molds can be designed on a CAD system and then CNC cut directly from the CAD file, or they can be fabricated by hand. The prototype mold is typically made of epoxy or wood.

Step Two: Molding Prototype Parts from a Prototype tool

The prototype tool we create will typically allow you to get a small lot of parts which allow you to test your product. In this stage, we will work on any fine tuning or adjusting that needs to be done. The parts that run off a prototype tool will typically not be of the same quality as an aluminum mold, but should provide enough information for design verification.

Step Three: Casting an Aluminum Mold

After the prototypes are approved, the pattern will be prepped for casting. Once the pattern has been prepped, we then send it to a foundry where an aluminum casting is made. The finished aluminum casting has embedded water lines that will help remove the heat from the tool and the plastic part during the production process.

Step Four: Molding Pre-Production Parts

When the new tool is received from the foundry, it will be set up and run to verify that all the desired dimensions and features are intact so that the finished part is built to your specifications. At this time, we recommend ordering enough parts to thoroughly test the product before full-scale production begins.

Material Selection Considerations

  • End-use application
  • Environmental
  • Indoor / outdoor temps
  • Impact & flammability requirements
  • Chemical exposure
  • Part life & function
Tool Cost Variations
  • Material
  • Complexity
  • Tolerances
  • Aesthetic requirements
Twin Sheet Forming is a process that involves vacuum forming two plastic sheets simultaneously by utilizing opposing female molds and bonding the two halves together while they are still hot. The result is a hollow finished piece which looks very similar to a blow molded product but with several cost and manufacturing advantages:
  • Increased structural integrity & rigidity
  • Enclosed cross section capability
  • Lower tooling cost
  • Internal reinforcement options (structural member, rigid foam, etc)
Request for Proposal
Interested in learning how your product can benefit from thermoforming at Prairie Plastics, Inc.? Submit your request for proposal to us today and find out!

Prairie Plastics, Inc.
522 Progress Way
PO Box 450
Sun Prairie, WI 53590
Ph: 608-834-9122
Fax: 608-299-3773