Circuit Board in Heatsink Embedded in Gray Rubber Material?

[111R]

I'm working on a brushless DC motor controller. The heat sink that contains the circuit board is completely embedded in a gray rubber type substance. It seems like it must have been filled with this as a liquid.

Any ideas on how to remove this material without destroying components on the board?

Thank you

 

[3DDave]

Different materials require different methods. Some of the methods require toxic or dangerous materials. Most of them require great care to avoid damaging the components and traces on the board. At the extreme end it may require multiple assemblies to experiment on.

There are plenty of YouTube videos and website discussions about how to deal with all of this.

I think most people, if it is soft, just dig slowly at it with a sharp knife/scalpel.

 

[TugboatEng]

As a cure in place rubber I would assume silicone or polyurethane. Methylene chloride will dissolve polyurethane. Here is a silicone manufacture's take'

https://www.google.com/url?sa=t&sou...Vaw2J_eT-TWijeNE9W9kB9F3R&cshid=1621403841129

 

[itsmoked]

If you are lucky enough to have a rubbery conformal coating just carve it out with an Exacto type knife (don't give your money to Exacto go with Excel), preferably a chisel point type.

Keith Cress
kcress -

http://www.flaminsystems.com