Chosen Solution
I want to practice reballing of IC on iPhone logic boards. I bough several iPhone 4S boards ver cheaply, but I have run into trouble: the components are covered with brown coating that prohibits access to the individual elements. The coating is very hard and so far I have failed to remove it with my precision knife. What is the trick?
@lacek that stuff is the underfill. A PITA to remove. I use some heat ~120deg C and a dental pick when I have to remove it. Check on something like this for an idea.
