Short Run Plastic Injection Molding: Benefits and Drawbacks

Short run plastic injection molding, also known as low-volume injection molding, is a manufacturing process used to produce limited quantities of parts.
Main topics

Some companies require Low-volume Production due to the nature of their product or their services. Short run plastic injection molding is an innovative approach that meets that need, offering a cost-effective and versatile solution for various industries.

Let’s explore what short-run plastic injection molding is, its advantages and disadvantages, and the types of projects that can benefit from this method.

What is Short-Run Plastic Injection Molding?

Short Run Plastic Injection Molding, also known as Low-volume Injection Molding, is a manufacturing process used to produce limited quantities of plastic parts. Typically, this involves production runs ranging from a few dozen to a few thousand units. Unlike traditional injection molding, which is optimized for high-volume production, short-run molding is designed to be flexible and economical for smaller batches.

Process Overview:

  1. Design and Prototyping: The process begins with the design and prototyping phase, often utilizing 3D printing or SLA (stereolithography) to create detailed models of the part.
  2. Tooling: Once the design is finalized, a mold is created. For short runs, tooling can be made from softer, less expensive materials like aluminum, which reduces cost and lead time.
  3. Injection Molding: The plastic material is heated until it becomes molten and is then injected into the mold cavity. After cooling and solidifying, the part is ejected from the mold.
  4. Quality Control: Each part undergoes rigorous quality checks to ensure it meets the required specifications.

Pros of Short-Run Plastic Injection Molding

Cost-Effective for Small Batches:

One of the main advantages of low-volume injection molding is its cost efficiency for small productions. Traditional high-volume injection molding requires significant investment in hard tooling and setup, which can be prohibitive for small quantities. Short-run molding uses less expensive tooling materials and faster setup times, making it more affordable.

Faster Turnaround:

This method significantly reduces lead times. The use of rapid tooling and streamlined production processes allows for quicker development and delivery of parts. This is particularly beneficial for projects with tight deadlines or those requiring quick market entry.


This method offers greater flexibility in design modifications and iterations. Since the tooling is less costly and quicker to produce, changes can be made more easily without substantial financial impact. This makes it ideal for prototyping and refining product designs before committing to high-volume production.

Lower Risk:

For new product development, this method allows companies to test the market and validate designs without the risk associated with large-scale production. This approach helps identify potential issues and gather customer feedback early in the process.

Cons of Short-Run Plastic Injection Molding

Higher Per-Unit Cost:

While the initial tooling and setup costs are lower, the per-unit cost of low-volume injection molding can be higher compared to high-volume production. This is due to the amortization of tooling costs over a smaller number of parts and less optimization in the production process.

Tooling Durability:

The tooling used in it, often made from aluminum or other softer materials, is less durable than the hardened steel molds used in high-volume production. This means the tooling may wear out more quickly, especially if the production volume exceeds the initial estimates.

Limited Material Options:

Short-run injection molding may offer fewer material choices compared to traditional methods. Certain high-performance plastics that require specific processing conditions may not be suitable for the rapid tooling and molding techniques used in short runs.

Ideal Applications for Short-Run Plastic Injection Molding

Prototyping and Product Development:
One of the most common uses of this approach is in the prototyping and product development stages. It allows designers and engineers to create functional prototypes that closely resemble the final product, facilitating testing and validation.

Market Testing and Limited Edition Products:
Companies can use short-run molding to produce limited quantities of products for market testing. This approach helps gauge consumer interest and gather valuable feedback before scaling up to full production. Additionally, it is ideal for creating limited edition products or customized items.

Bridge Production:
Short-run molding is an excellent solution for bridge production. This involves producing parts in small quantities to meet immediate demand while the tooling and setup for high-volume production are being completed.

Replacement Parts and Spare Components:
Manufacturers can use it to produce replacement parts and spare components for machinery, equipment, or consumer products. This is particularly useful for industries where maintaining a large inventory of spare parts is not feasible.

Specialized Industrial Applications:
Industries such as medical devices, aerospace, and automotive often require specialized parts in small quantities. Short-run plastic injection molding can produce these components with high precision and quality, meeting industry standards.

At ARRK, we specialize in providing comprehensive Product Design and Development. Our expertise in manufacturing solutions ensures that we can meet your specific needs and help bring your innovative ideas to life. Contact us today to learn more about how we can support your next project. Learn more with our blog content, such as, master model manufacturing: key components and advantages or how are monitoring drones revolutionizing surveillance?.

Begin Your Journey with Expert Support

If you’ve got your design files at the ready and are eager to see your ideas materialize, you’re in the perfect spot!
Ready to take the first step but unsure about the details? Get in touch with us for a seamless start to your project’s journey.