Introduction to Injection Mold Fabrication


It can take a few weeks to make an injection mold, but it may take months for complex ones.


Molds for plastic injection can be tricky. Some molds are basic and some are very complicated. Sometimes its the availability of the chosen material that holds up the process.

The time it takes to create an injection mold can vary significantly, depending on the complexity of the design and the specifics of the materials used. Understanding mold fabrication is helpful for any business owner, utilizing injection molding companies to plan and execute production efficiently.

JDI Plastics knows a thing or two about the time it takes to make an injection mold. We have the experience and capabilities, as well as high-quality suppliers, to provide your business with precise plastic parts at scale

Key Takeaways: 

  • Time Frame: Mold fabrication can range from a few weeks to several months.
  • Complexity: The more complex the mold, the longer the fabrication time.
  • Materials: Availability and type of materials directly impact lead times.
  • Customization: Custom requirements can extend the fabrication process.
  • Efficiency: Advanced planning and design can significantly reduce time delays.

How Long Does It Take to Make an Injection Mold?

Typical Time Frames to Make an Injection Mold

The timeline for fabricating an injection mold can vary widely, primarily depending on the mold’s complexity and design. 

Typically, a simple mold might take anywhere from 2 to 4 weeks to complete, while more complex molds could require 6 to 8 weeks or more. 

This variance is due to the intricacies involved in designing and machining the mold to meet precise specifications. 

The table below provides a clearer picture of how different types of molds stack up against each other in terms of fabrication time.

Fabrication Time for Different Mold Types

Mold Type Simple Molds Complex Molds Prototype Molds
Timeframe 3-4 weeks 6-10 weeks 2-3 weeks

Simple vs. Complex Molds

When comparing simple and complex molds, the primary difference lies in the fabrication time. 

Simple molds, typically used for less intricate parts, can be completed relatively quickly due to their straightforward design and fewer cavities. 

In contrast, complex molds require more time because of their detailed features, multiple cavities, and the need for precise engineering and testing. The complexity not only adds to the design and manufacturing time but also necessitates additional rounds of testing to ensure quality and functionality. (1)

Prototype vs. Production Molds

The distinction between prototype and production molds is significant in terms of their fabrication time. Prototype molds, generally used for initial testing and validation of a design, are made quicker – often within 2 to 3 weeks. 

These molds are not intended for high-volume production but rather for creating a limited number of parts to assess the design’s viability. On the other hand, production molds, designed for mass manufacturing, take longer to fabricate. 

This extended timeframe, typically 4 to 10 weeks, is due to the need for durability and the ability to withstand high production volumes without compromising the quality of the parts produced.

Understanding the Injection Molding Process

Injection molding is a cornerstone of modern manufacturing, known for its ability to produce high volumes of plastic parts with precision.

The process begins with designing a mold, which is then used to shape molten plastic into the desired form. This method is renowned for its efficiency and versatility, making it a preferred choice for a wide range of products, from simple household items to complex medical devices.

Steps in the Injection Molding Process

  • Design: Creating a detailed mold design based on the part specifications.
  • Material Selection: Choosing the appropriate plastic material for the part.
  • Mold Creation: Designing and fabricating the mold, often from steel or aluminum.
  • Molding: Injecting molten plastic into the mold and cooling it to form the part.
  • Finishing: Applying any necessary post-molding processes like painting or assembly.

Factors Influencing Mold Fabrication Time

The time required to fabricate an injection mold is not a fixed value but varies based on several key factors. These include the complexity of the mold design, the type of materials used, and the specific requirements of the project.

Complexity of the Mold Design

The complexity of a mold’s design is a primary factor in determining its fabrication time. 

Intricate designs with detailed features, multiple cavities, or complex geometries require more time for both design and manufacturing. Some of the mold features that cause extensive time requirements are slides, lifter, core functions, and many more.  

The precision needed for these molds often necessitates additional testing and refinement, further extending the timeline.

Material and Component Availability

The availability of materials and components needed for the mold can significantly impact the overall lead time. 

Delays in sourcing the right materials or specific components can push back the start of mold fabrication. The choice of material, whether it’s a standard or a specialized one, also plays a crucial role in determining the timeline.

Custom Requirements and Specifications

Custom requirements and specifications can add to the complexity and time needed for mold fabrication. 

Tailored designs, unique material needs, or specific tolerances demand additional attention and time in both the design and manufacturing stages. Custom molds often require more iterations and testing to ensure they meet the exact needs of the project.

Overcoming Delays in Mold Fabrication

Minimizing delays in mold fabrication is crucial for maintaining project timelines and ensuring efficient production. 

The key lies in proactive planning and precise execution. By identifying potential bottlenecks early and implementing effective strategies, manufacturers can significantly reduce the risk of delays. 

Streamlining the design process, choosing readily available materials, and maintaining clear communication with all stakeholders are vital steps in this direction.

  1. Early Design Finalization: Lock in designs early to avoid last-minute changes.
  2. Material Selection: Opt for materials that are readily available to avoid sourcing delays.
  3. Effective Communication: Maintain clear, ongoing communication with the design and fabrication teams.
  4. Advanced Planning: Schedule and plan each stage of the mold fabrication process meticulously.
  5. Quality Control Checks: Implement regular quality checks to catch and rectify issues promptly.

Conclusion: Maximizing Efficiency in Mold Making

The time it takes to fabricate an injection mold can vary greatly, influenced by factors like mold complexity, material availability, and custom requirements. 

JDI Plastics understands these bottlenecks in the process. We offer a streamlined yet tailorable system to provide our clients with the highest-quality precision injected plastic parts 

By focusing on efficient planning, clear communication, and leveraging a deep understanding of the injection molding process, JDI Plastics consistently delivers superior results, reinforcing our reputation as a trusted partner in the manufacturing industry.




  1. How long does it take to get an injection molded part made?, Elaine Chen,