Since this thread seems to get referenced by me and a few other people occasionally, I thought I'd add a footnote;
The pins on the LGA grids are copper. This is, without work hardening, a particularly ductile material that can be bent a lot without inducing metal fatigue failures.
It would seem that the pins on an LGA are extensively work hardened for springiness, and possibly even tempered a bit by the tool that makes them. At any rate, if a pin goes through more than about 60 degrees of plastic deformation, there's a good chance it will shear (the stress fractures will already have been created during the inititial knock that bent it).
Given that Foxconn make pretty much every LGA socket, I'm going to say that to make a correction you're going to have to overcompensate for the metal's hysterisis by about 10-15 degrees. What that means, for the non-engineers, is that if a pin is out to the left by 30 degrees, move it right 40-45 degrees. This should get it right first time. The fewer total degrees of movement you force the metal through, the less chance you have of snapping it off. 90 degrees just shears the pin right off (tested for **** 'n giggles on a dead board).
Put it this way. To correct a 30-degree bend the correct amount the first time requires you to move the pencil/tube/straw 40-45 degrees.
If you don't go far enough - no problem, put the pencil/tube/straw back and keep bending. This won't overwork the metal because you're not causing any plastic deformation (permanent bend), you're only stressing the metal in elastic deformation (does what it says on the tin - springs back unaffected).
If you go too far, you have to add the overshoot to the correction - so a 30 degree correction, overshot by 10 degrees and then corrected is the same as a 50 degree repair. It's going to be weak as hell but it'll work. Overshoot the other way and then recorrect and you're probably going to be looking at 70 degrees in total. Assuming the pin stayed in place, plugging the CPU in will probably be enough force to snap that pin anyway.
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