You have completed your search for an ideal conformal coating chemistry, one that will provide your PCBs the protection and reliability demanded by your industry and customers. After all that work, you probably assume your job is finished. Our apologies for being the bearer of bad news: There is still work to be done. In this basic presentation and discussion, we will talk about the proper choice and implementation of thinners for your coating. In many cases, a mistake in thinner can harm or even completely negate the protective properties of your conformal coating when applied to your PCB.