Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here


PCB overmolding

PCB overmolding

PCB overmolding

PCB Overmolding is required. In Past, we had used PA678 material with low pressure molding provision. But it attracts moisture through cables inside PCB. What should be the best alternative to avoid moistures. Now we are looking similar low pressure molding but need to avoid moisture inside. Please advise!

RE: PCB overmolding

Can parylene coating be done before overmolding? will it work?

RE: PCB overmolding

Yes. We had similar problems with moisture intrusion along hardware seams and wire strands. Parylene coating over the fully assembled and soldered boards, prior to overmolding, got us around it. We tested by immersing the overmolded boards in water; previously overmolded boards failed due to water intrusion in about 24-48 hours. I think the latest coated boards went well past 2 months. Talk to a parylene coater about which of the varieties of parylene you want, some are more water resistant than others.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members! Already a Member? Login


White Paper - Considerations for choosing a 3D printing technology
The adoption of 3D printing into major companies’ product development life cycles is a testament to the technology’s incredible benefits to consumers, designers, engineers and manufacturers. While traditional production methods have limitations in manufacturability, 3D printing provides unparalleled design freedom due to the additive method of building parts layer by layer. Download Now
White Paper - Are all 3D printed metals the same?
With so many different 3D printing metal systems and processes today, how can you know exactly what you’re getting? Today, there are several different methods for manufacturing 3D printed metal components with their own strengths and limits. Download Now

Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close