Good day, I'm still working on mounting my ZEROtherm NV120. I got stuck installing the heatsink because I needed a long phillips screw driver to turn the mounting screws into the back plate. I need to go buy a long shank screw driver. This delay gave me the opportunity to think about the installation a bit.... The question that jumped into my mind was this. To what torgue value do I tighten the screws? I don't want to crush the chip or stress the board any more than necessary but want to make sure I get a good contact betweent he sink and the chip. Anybody have a number? Thanks, Phil ps, the heatsink manual gives no indication of how tight.
Looking at the mechanism, I'd say the springs will limit how tight you can get it, although it's not always a completely concrete method, it works nicely on my HR-03GT, which has screws over the mounting bolts. They don't stop you over-tightening, but it's pretty obvious when it's well seated.
The spring is an interesting idea but does not ensure you get the right mounting force. When tightening the screws, the amount of force applied is directly proportional to the amount of compression of the spring based on the formula Force=SpringConstant x Defletion. This formula holds true until the spring is completely compressed. At full compression, the bolt tries to compress the metal of the spring and the force rises dramatically, as if you were clamping without the spring. If the spring was removed and the screw clamped down on the base plate then the base plate behaves as a very rigid spring with a near infinite SpringConstant. In other words, the spring provides a method to slowly ramp up the holding force, provided you don't fully collapse it. But, you still come back to the same question. How much force is the right force? Obviously it's within the compression range of the spring, but where? btw, I'm an engineer. Phil
I have that heatsink and the correct amount of pressure is when the screw is completely through. The heatsink won't let you go any further. You'll know when it gets to that point. If I'm completely missing what you are asking then sorry. Your second post confused me somewhat.