Solve Consistency Issues with Automated Conformal Coating Inspection

Automation continues to be a driving force behind high-quality electronics manufacturing, and for good reason. It makes outcomes more predictable. Quality, consistency, and operator safety are all improved. More and more production processes are benefiting from automation including conformal coating inspection.
In a manual process, operators inspect coated boards for adherence to keep out zones, accurate coating thicknesses, the existence of bubbles, and consistent coverage. This requires a high-level of skill and experience that’s honed over time. How much skill? Let’s look at one example. When verifying coating thickness, operators must learn to visually assess the level of light or “glow” emitted from the coating material under UV light. Although an operator can achieve an acceptable level of qualitative accuracy, it would not be possible to match the accuracy of automated inspection. Like any manual process it’s difficult to achieve repeatability. Results vary from operator to operator and human error is unavoidable. Other common concerns include over exposure to chemicals and fumes affecting operator safety and damaged boards due to frequent handling. If you’re trying to manage any of these concerns, automation is the solution.
The Nordson ASYMTEK FX-940UV Series automates the conformal coating inspection process – working together with the Select Coat SL-940 Conformal Coating system to deliver ongoing coating quality and consistency. Programming and operations methods can be combined to create an efficient coating line that maintains repeatability across batches. The system is SMEMA compatible and available in batch and inline configurations to accommodate varied manufacturing floor space needs. How does it work? There are two powerful modes.
Large Area Grid Inspection Mode (Auto-Tune)
In Auto-Tune mode, the system scans known good boards and the software “learns” the variations across coated areas to capture the passing criteria. This method is excellent for quick inspection recipe development. The system’s automatic learning capabilities enable the inspection of coated and non-coated areas within minutes of scanning the first article.

Individual Part Inspection Mode
In this mode, the system analyzes critical areas for coverage, non-coverage, and coating thickness. Areas around fillets can be inspected and selective bubble detection can be performed. When paired with optional side cameras, the sides of components can also be inspected.

The FX-940UV Series makes inspection of conformal coatings simple and convenient – providing complete inspection coverage at unmatched low false-failure rates. Advanced High-Power UV Lighting and image processing technology support coverage inspection, color inspection, normalized correlation, and rule-based algorithms.
In our next post, we’ll discuss how you can use FX-940UV process data to gain better control over your conformal coating process prior to inspection.
For more information, please contact us at asktheexperts@nordsonasymtek.com.