One Size Does Not Fit All: Why Use Custom Resins for Injection Molding

Home Blog
By: Liz Lipply | September 26, 2019

Injection molding is a tried and true manufacturing method that has experienced small, incremental changes over the years. It used to be, if you had a product or part to be manufactured, your injection molding manufacturer would provide you with a list of polymers to choose from. Your design and engineering teamcustom resin square peg would work together along with the injection molding team to select a resin that would suit your needs. A variety of factors would be considered including durability, cost, flexibility and cosmetics.

Ready for a secret? It still works like that.

With most manufacturers, you are going to need to select the resin for your part from a list of available options. However, modern facilities have moved into a more advanced method of providing an option not previously available on that list—custom engineered resins.

Advances are being made relatively frequently in polymers and resins. This is one area where science and technology continue to improve. But, when there are literally hundreds—even thousands—of resins available, why would you need something beyond traditional choices? Read on to learn why developing a custom engineered resin may be the best, most cost-effective way to manufacture a product.

Custom Resin May Lower Costs

At first, it might seem that selecting a custom engineered resin would cost more than going with a readily available option. While there will certainly be an upfront cost that you would not otherwise incur—the cost to research and develop the resin, this is a one-time fee.

With all the various features to consider when it comes to resins including ductility, rigidity, dimensional stability, temperature tolerance, chemical resistance and more, there are many variations and trade-offs. You might find what appears to be the perfect resin for your product, but it may be in limited supply or material costs could be high.

By developing your own resin, you are better able to control the supply and cut out the frustration of dealing with additional suppliers and middlemen. Also, it may also be possible to have the resin developed in closer proximity to the injection molding plant. This means you may cut down on supply and transportation costs associated with a project.

What if you don’t need all the features of a more expensive resin, but you need an enhanced rigidity? Working with a manufacturer that can custom engineer resin solutions can help meet your needs and save money, especially when you’re dealing with large and potentially repeated production runs. Why pay for features you don’t want?

Choose a Custom Resin When you Need Specificity

As previously stated, there are already a lot of options available when it comes to resins and polymers for injection molding. However, certain applications have very specific needs. When designers and engineers are working to produce a part that your business depends on, getting everything right is critical.

With existing resins, you may end up making trade-offs. One resin may have the ductility you are looking for, but may not be electroplatable. Luckily, customized resins can give you everything you need for your specifications.

What if your project has requirements that no one else has brought forth before? That is a case where you would want to work with a resin specialist who can create a resin that fits your product. It’s also important to note that this unique mix may be created just for your company but it could become available to anyone. So, always check contracts, especially if you are concerned with trade secrets.

Ensure Consistency Over Time

In manufacturing it comes as no surprise that parts, components and mixtures can vary greatly over time. If you are relying on a specific company for your resin, you are, in a way, at their mercy. If they have production issues, you will have production delays or other problems.

By developing a proprietary resin compound, you have more control over your supply. This may mean working with additional manufacturers to produce enough resin for your projects. It might also mean working to ensure that your resin mixture can continue to be manufactured, even if another company falters or discontinues a resin, filler or modifier. There are a number of sources for base resins and compounding services available.  Resin manufacturers may make small changes over time that offer a similar or comparable product, but it is not always the same. If you want the highest level of consistency, you need to be in control of your own resin.

Ferriot, Inc. can work with you to make sure you have the best possible resin for your project. If the resin does not already exist, we will help you create a proprietary resin solution. We understand the demands of high production injection molding for a variety of industries including aerospace, automotive, and medical devices and we will go to great lengths to make sure that your product is the best it can possibly be. Schedule a consultation today to learn more about custom engineered resin or click on the image below to download our workbook on selecting the right resin for your project.  

Learn more: 


Get the Injection Molding Resin Selection Workbook

Recent Posts

How Can We Help?


Ferriot’s experienced engineers are here to guide you through every critical step in your injection molding journey, from concept to completion.