By Tom Seratti, President, SMT Supplies
In my years working closely with production managers and engineers in the electronics manufacturing industry, one recurring issue I often hear about is conformal coating defects. These defects can create serious headaches on the production line and lead to costly rework, delays, and even dissatisfied customers. I’ve spent much time discussing solutions with industry experts to know what works—and what doesn’t—when it comes to preventing these defects.
Whether you’re just starting to explore conformal coatings or looking to improve your existing processes, here are some tried-and-true strategies I’ve gathered from the field.
- Choose the Right Coating Material
One of the most important factors in preventing defects is selecting the appropriate conformal coating for the job. Each material—whether it's acrylic, urethane, silicone, or parylene—has its own strengths and weaknesses. I always advise my customers to work closely with their suppliers to ensure they’re using the right coating for the specific environmental conditions their products will face.
I can’t tell you how many times I’ve seen teams run into trouble simply because they didn’t fully understand the curing requirements or application methods for their coating material. It pays to get it right from the start.
- Fine-Tune Your Application Process
I’m often asked which application method is best: spraying, brushing, or dipping. While each method has its place, ensuring that your process is optimized for consistency is key. Spraying often provides the most uniform results, but it’s crucial to dial in settings like spray pressure and pattern.
I’ve seen customers achieve great results by doing test runs before moving to full production. It might take a little extra time, but catching issues early saves you from the pain of defects further down the line.
- Control the Environment
This one comes up in nearly every conversation I have with production managers—environmental conditions play a massive role in the success of conformal coatings. Humidity and temperature can both affect how well the coating adheres and cures. Too much moisture can cause bubbles or delamination, while a poor temperature range can extend curing times or cause uneven coating.
I always recommend setting up environmental controls in your coating area to ensure consistent conditions. It’s one of those small investments that pays off big when it comes to avoiding defects.
- Emphasize Surface Cleanliness
I’ve learned from my clients that no matter how advanced the coating process is, if the surface isn’t clean, defects will follow. Dust, oils, and other contaminants can wreak havoc on adhesion. Making sure that components are cleaned properly before coating is an essential step that sometimes gets overlooked.
Many production managers I work with have implemented stricter cleaning protocols, such as using gloves when handling parts and adding extra cleaning steps with specialized equipment, like ultrasonic cleaners. The results? Fewer defects and more reliable coatings.
- Stay Ahead with Training
One thing I’ve learned from working with production teams is that even the best tools and materials can’t replace a well-trained team. Training is crucial for preventing conformal coating defects. Regular workshops and updates on the latest application techniques and best practices can go a long way toward maintaining quality. Our supplier, Techspray, has an excellent webinar on Conformal Coating Defects – How to Diagnose, Repair, and Prevent.
Explore High-Quality Coating Solutions: Techspray and Chemtronics
When it comes to conformal coating, using high-quality products can make all the difference in preventing defects. Two brands we often recommend at SMT Supplies are Techspray and Chemtronics. Both offer a wide range of conformal coatings that are known for their reliability and ease of application. Techspray’s acrylic-based coatings are particularly popular for their quick drying times and easy rework ability, while Chemtronics provides a variety of silicone and urethane coatings designed for harsher environments. Many production managers I work with have seen fewer defects and improved protection by switching to these trusted brands. If you haven’t considered them yet, it’s worth exploring how they can fit into your production process.
Final Thoughts
Preventing conformal coating defects doesn’t have to be an uphill battle. By choosing the right material, refining your application process, controlling environmental conditions, maintaining a clean surface, and investing in both technology and training, you can significantly reduce the risk of defects in your production line.
As someone who works alongside electronics manufacturers every day, I’ve seen these strategies work time and again. If you’re facing challenges with conformal coating, we’d be happy to discuss possible solutions or help you find the right products for your specific needs.
Contact us — we’re here to help make your production run as smoothly as possible!