• March 18, 2025
Last updated on April 2nd, 2026
When investing in injection molding solutions, it’s important to understand what splay is and how it plays a role in the outcome of your final product. In this post, we’ll walk through what injection molding splay looks like, why it’s problematic, and solutions to avoid this defect in your injection products.
What Is Injection Molding Splay?
Splay is a cosmetic defect in injection molding that appears as silvery streaks or blemishes that resemble star bursts on the surface of a plastic part. This can affect both the appearance and the performance of the part.
Common causes for splay in injection molding include:
- Hygroscopic plastics – Plastics such as nylons or polycarbonates are hygroscopic. This means that they naturally absorb moisture from their surrounding environment, causing the plastic to degrade when brought up to heat during the manufacturing process. Because of this, these plastic types must be dried before processing to help remove the moisture.
- Overheating materials – When materials are heated, if the injection speed is excessive, or the barrel, manifold, and drop temperatures are too high, this can cause splay in injection molding.
- Improper equipment – If your equipment is not properly sized or designed for injection molding, this can create splay as well. Improperly sized nozzle tips, sprues, gates, or mold geometry can all lead to issues during the manufacturing process.
Why Is Splay in Injection Molding Problematic?
Splay can be problematic for various reasons. First, it affects the final product visually, leaving streaks across the injection molding. When trying to maintain product standards, this can be an unacceptable development, and you may be required to redo the injection molding process. This results in more time and money spent.
Additionally, injection molding splay can also cause the final product to function improperly. Specifically in hygroscopic resins, the physical properties of the resin will degrade, causing the final product to be brittle. This also causes the product to not meet quality standards.
Overall, splay is a defect that creates issues with the final injection molding product’s appearance, quality, and performance, so it’s an issue that should be avoided.
How AdvancTEK Prevents Splay
When seeking out an injection molding supplier, you’ll want to ensure that any company you choose provides you with the best quality products. AdvancTEK is a leading provider of injection molding services, and we take the necessary measures during our injection molding process to prevent splay.
Some ways we work to prevent splay in injection molding include:
- Ensuring plastics are dried
- Using non-hygroscopic plastics
- Avoiding high temperatures
- Verifying that machinery is properly sized
With our team’s focus on providing the highest quality injection molding products, you can feel confident that our injection molding parts will be free from splay and meet your expectations and standards.
Why You Should Choose AdvancTEK
At AdvancTEK, we work to bring your ideas to life, as we offer design and development services that deliver custom solutions. If you have a design in mind, you can bring it to our team, and we’ll work closely with you to produce the product you’re looking for.
We also work with a variety of industries, putting our more than 35 years of experience to use in providing injection molding solutions. These include fields such as:
- Industrial
- Medical
- Battery and energy storage
- Telecommunications
- Powersports and recreation
- Construction and agriculture
As you attempt to avoid splay in injection molding and acquire the best quality products, AdvancTEK is your manufacturer of choice with extensive industry experience.
Avoid Splay Injection in Molding with AdvancTEK Today
If you’re searching for a reliable manufacturer who provides high-quality injection moldings, contact us today to get started on your next project.
