Welcome to Part 3 of our series covering all aspects of injection molding: tools, considerations, and applications. In Part 3, the conclusion of the series, we feature family molds.

Family molds are similar to multi-cavity molds in that they contain two or more cavities within the family mold layout to produce multiple pieces per cycle. The fundamental difference with family molds is that they are designed to make different parts within the same mold tool. 

The typical practical application of a family mold is as follows: 

  • Producing various components and parts for a larger or more complex product
  • Using the family mold to create, for instance, two opposite halves of a housing assembly that can snap together, or multiple plastic components for a medical device

Next, we’ll look at some pros and cons of using a family mold for injection molding:

Pros

  • High-cost efficiency over the mold’s life span, with the need to only produce one mold tool instead of several
  • Faster overall production times, making multiple part types in one cycle
  • The ability to manufacture several part forms in one mold tool, with two being just the minimum

Cons

  • Increased engineering complexity, with the need to account for varying resin flows, holding times, and cooling times — as well as more complex runner layouts
  • Higher upfront production costs due to this increased complexity
  • Greater susceptibility to part defects

Next, we’ll cover types of applications where a family mold would be the right choice.

Family Mold Uses for Injection Molding

The below examples are some of the best-suited scenarios for family molds:

  • Products where numerous parts and components can be manufactured from the same material, with the same appearance (e.g., material color)
  • Scenarios where fast time to market and high productivity are critical
  • When working with a mold manufacturing partner that can conduct flow analysis to reduce the chance of part defects and help ensure you gain full advantage of the speed benefits of family molds
  • High-volume applications where the form and appearance of components are unlikely to be changed in the near future (this should enable the maximum ROI for the higher upfront cost of a family mold)

Crescent Industries offers a broad range of tooling solutions for injection molding — including expertise in family molds, single-cavity, and multi-cavity molds — with capabilities for up to 96 parts per cycle. We look forward to sharing our expertise to help you develop the best mold tooling solution for your project. 

To learn more about our services and to discuss your project with us, contact Crescent Industries today.


Resources:

http://www.mhs-hotrunners.com/familymolding.html

http://www.janler.com/CombinationFamilyMolds.html

https://www.smlease.com/entries/plastic-design/single-cavity-multi-cavity-and-family-molds/

https://www.plastopialtd.com/family-mold/

https://www.crescentind.com/tooling

Topics: injection mold building