I have a PCB with a big piece of aluminum used for heatsinking. The CNC'd aluminum touches all the hot components (DDR, power regulators, etc) using 1mm-thick thermal pads. There are 30 pads on the aluminum (ie. 30 components on my PCB need to be cooled).
Thermal pads come in 3 flavors: not sticky, sticky one side, and sticky two sides. I use sticky one side.
The problem is during disassembly: despite one side not being sticky, with 30 pads shmushed in there, separating the aluminum from the PCB requires alot of force, with much wedging/peeling/fiddling, and most importantly, bending of the PCB, which breaks my BGA solder joints.
So the question: Anyone have any bright ideas on how to disassemble the heatsink from a PCB that has lots of thermal pads?