Designing for Selective Robotic Conformal Coating Processing: Rule 13 “Sticking coatings to non stick silicones is a pain”

Applying silicone RTVs to circuit boards to provide support to components for long term reliability is fine. Just don’t do it before you apply a conformal coating to the surface unless the conformal coating itself is a silicone. Acrylic and urethane coatings do not stick to silicone. So, don’t try unless you want defects appearing.

Rule 13

If you call out silicone staking materials for ruggedisation purposes, use a silicone conformal coating. If you don’t want to use a silicone conformal coating, then use a urethane or epoxy staking compound.

The Rules

The Rules for Selective Conformal Coating are straightforward. Follow them and you can save money and time in your application process. However, if the Rules are not followed, the resultant circuit board design can challenge even the most sophisticated conformal coating system and its operator to achieve the finish desired.

Click Designing Circuit Boards for Selective Robotic Conformal Coating for further Rules.

Advertisements

Tags: , , , , , , ,

About Dr Lee Hitchens

Dr Hitchens has been working in the electronics industry and the area of conformal coatings for over 25 years in various areas including sales and technical support. He has also been training people for almost the same amount of time in all areas of conformal coating whether that is materials & equipment selection, process development or troubleshooting to help them solve their particular problem. Recently, he decided that the industry needed a specific place where all of the useful knowledge on conformal coatings could be collated for users to find easily and use in their own production process. So, Nexus was born and he began the Nexus eBook project.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: