Identify Sealant on PCB

Discussion in 'General Electronics Chat' started by spudgun00, Apr 15, 2013.

  1. spudgun00

    Thread Starter New Member

    Apr 15, 2013
    I'm trying to identify a potting on this PCB. It is attached to a vehicle so it must be quite maleable and 'tough' to handle the jarring and occassional stress. My understanding is that it probably won't be Epoxy as it's too hard and will crack under stress.

    So what is it? Polyurethene? Silicon?

    Also how do I remove it? I heard the if its Epoxy then you would use a heat gun and a scalpel. Is it the same process if its Polyurethene or Silicon?
  2. Kermit2

    AAC Fanatic!

    Feb 5, 2010
    It looks like a standard blob of self vulcanizing rubber silicone sealant. Nothing much will affect it but it is soft and can be removed with a razor blade. strong acetic acid (vinegar) may be able to remove any residue left after you have mechanically removed most of the mass.

    For other types of PCB coatings....

    First try alcohol

    Then try acetone

    Then try dichloromethane(brake parts cleaner)

    If none of those work try letting some hydralic brake fluid soak into a small area for several hours and repeat the wash with acetone on the softened area.

    if these don't affect the substance then you will have to resort to a heat gun and scraper