PVA Pro Tip #27: Mastering Bubble-Free Coating – Frequently Asked Questions
Mastering Bubble-Free Coating with Selective Conformal Coating Systems
Bubbles at component corners? Learn how programming techniques and underfill strategies can eliminate air entrapment during the coating process.
Q: How can programming my selective coating robot influence air entrapment, and how do I perform an underfill using a detailing valve?
Programming impacts coating flow and air entrapment. Using a detailing valve such as the JDX, apply coating to two opposing edges to allow capillary action to pull material underneath and force out trapped air before the main coating. PathMaster X’s drag-and-drop and offline programming make this process faster and more precise.
Q: What might be the reason for seeing bubbles at the corners of components even after the conformal coating has fully cured?
If you observe bubbles at component corners post-cure, it’s likely that air was entrapped during the coating application process itself.
Q: What is an “underfill” process in the context of applying conformal coating?
In this context, an underfill process is a strategic technique used on components that have the potential to trap air during the regular conformal coating application.
Q: How does employing an underfill process help in preventing the formation of bubbles around components?
By applying an initial layer of coating to specific edges of a component, the underfill process allows any trapped air underneath to escape before the component is fully encapsulated by the main coating layer.
Q: After completing the underfill process on certain components, can I proceed with the general spraying of conformal coating over the entire circuit board?
Yes, once you have performed the underfill on the necessary components, you can confidently proceed with spraying the conformal coating over the rest of the circuit board without worrying about producing bubbles around those specific components.