Yellow Epoxy Like Material on PCB?

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The discussion centers around a yellow epoxy-like material found on a PCB, speculated to be a two-part polyurethane used for protection against vibration and environmental damage. Participants express curiosity about its removal without damaging the PCB, with suggestions including paint strippers like dichloromethane. Concerns are raised about the safety of using such chemicals, especially without proper equipment and experience. The voltage of the PCB is clarified as 12 V DC, indicating it is not high voltage. Understanding the material's composition is essential for determining the safest removal method.
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I've seen the black epoxy on various pcbs to encapsulate it. I've also seen plenty of times a Clear coating. But this is my first time seeing this yellow stuff? Any idea what it is?
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BuddyBoy said:
But this is my first time seeing this yellow stuff? Any idea what it is?
My guess would be a two part polyurethane, being used there to protect surface components from vibration, physical and environmental damage.
 
Baluncore said:
My guess would be a two part polyurethane, being used there to protect surface components from vibration, physical and environmental damage.
Hey thanks. Any idea on how to remove it without damaging the PCB or what's underneath it?
 
BuddyBoy said:
Hey thanks. Any idea on how to remove it without damaging the PCB or what's underneath it?
Why do you want to remove it?

If you knew exactly what it was, you could probably find out what the recommended removal chemical is. But as @Baluncore implies, such chemicals are usually pretty dangerous and should not be used unless you have access to a chemical fume hood and experience using hazardous chemicals.
 
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