Prototype Molds Speed up the Production Process

Posted by Al Timm on Aug 28, 2013 11:00:00 AM
Al Timm

blank.pngA surprising number of projects are completed without using a prototype mold—the general idea being that a prototype mold isn’t really necessary and is just an extra step that slows down overall development and production and adds cost. Actually, just the opposite is true—without a prototype mold, a lot of adjustments are usually required on the production tool, which drives up cost and delays production.

Depending on the complexity of the part, prototype tooling costs are typically 20-40 percent of production tooling costs. This is a result of softer tooling materials (faster cutting), usually single-cavity prototyping instead of multi-cavity production, and fewer bells and whistles compared to a production tool. Advantages to using a prototype mold include:

  • Ability to test different plastic materials. At this low-volume level, any material that can be molded in a production mold can also be run in a prototype mold, making this an effective way to test material performance before making a final selection.
  • Confirm that the part geometry is feasible. This is the perfect opportunity to see if the part fills properly without defects (voids, weld lines, flow marks, burning, sinks). If there are problems, it’s okay to weld and/or cut up the prototype tool because it has an inherently short lifespan, with the main goal of gathering data (much more caution is required for modifying production tools).

  • Optimize gate locations. The prototype mold can be welded and recut to change gate locations and test them prior to production. This eliminates the cost and lost time in modifying the production tool, which can reduce performance and shorten lifespan.

  • Modify mold to improve geometry as needed. The prototype mold can be revised (for example, adding or removing wall thickness, ribbing, radii) to perfect the part geometry for production. The new dimensions are then test-run in the prototyping mold, without taking the chance of damaging the production mold (or making adjustments).

  • Ideal for complex parts with difficult geometry. Tooling components like lifters and slides that are used to form undercuts in production molds are very expensive and not practical for a prototype mold. However, hand-loaded inserts can be used instead to test these features in the prototype mold, creating undercuts and other challenging geometry. 

  • Saves production time. Overall, it is quicker and cheaper to make tweaks on a prototype mold compared to the production mold.

Kaysun has the resources and experience to design, create, and revise prototype molds in-house—a competitive advantage in the industry. The information learned from the prototyping phase will lead to a final design that will require far fewer revisions to the production mold to make it production-ready. It also improves the long-term integrity of the production mold. This approach, up front, saves time and money on the back end of the project, optimizing cycle times and reducing overall production costs.

There is a keen interest in rapid prototyping and additive manufacturing these days—however, prototypes made from these processes lack the valuable production data that is gathered from prototype molds, such as ideal gate locations, fill rates, cooling rates, etc. Prototype mold results give engineers the information they need to identify and correct any part design or production challenges, resulting in a production process that maximizes manufacturability and speed to market.