Structural Foam Molding Troubleshooting: Common Problems and Their Solutions

While structural foam molding is a very popular manufacturing process, some common issues can pop up during production. Fortunately, an experienced structural foam molding partner will be able to easily overcome and resolve these issues. So, what does structural foam molding troubleshooting look like? Let’s explore the most common issues and how you can fix them.

Structural Foam Molding Troubleshooting Common Problems

Sink Marks

When one region of the product cools more slowly than others, thicker regions may result, known as sink marks. This commonly occurs when the inner core of the product cools too rapidly, leading to depressions on the part surface, however, it can also be a result of inadequate venting during the production process.


Warping refers to part deformation caused by non-uniform cooling. This common issue can pose large issues for companies, as it makes the part unsuitable for its intended purpose. Warping is typically caused by an improper cooling rate and poor mold design.

Issues with Part Filling

When the mold is not filled all the way, the part filling will not form as intended. This causes the part to miss sections, making the product impossible to use. Generally, issues with part filling are caused by improper ventilation and inadequate material flow during the production process.

Fixing Common Structural Foam Molding Issues

Sink Marks

In order to prevent sink marks, you will need to re-evaluate parts of your manufacturing process. The best way to fix these issues is to adjust the cooling process so each area of the product cools at the same rate. This can be accomplished by implementing cooling channels and ensuring your mold is designed properly and contains adequate venting channels.


Since warping is also caused by improper and non-uniform cooling, you will need to adjust your manufacturing process to ensure the cooling process is ideal. This includes managing the cooling temperatures, implementing strategic cooling channel placements, and employing support structures to prevent the material from sinking.

Issues with Part Filling

To resolve issues with part filling, it is important to pay close attention to the design of your molds. Ensuring proper gate design and location and improving the ventilation of the mold will help prevent the mold from filling improperly.

Port Erie is Here for All of Your Structural Foam Molding Troubleshooting

Port Erie Plastics has been providing structural foam molding and injection molding services since 1953. In those years, we have gained unparalleled experience in each process and are able to easily identify issues as soon as they arise and make the necessary adjustments so you don’t lose valuable time and money during your production process.

We will assign an experienced plastics engineer to your project who will help you with finding alternative plastics, designing for manufacturability, and making sure the manufacturing process is going smoothly. Our team can also help you with your warehousing and distribution needs. With our two 100,000-square-foot warehouses and 75,000-square-foot storage facility, we can help with your project from start to finish.

Are you ready to start your structural foam molding project? Contact our team today.

Comments are closed