Hi I did a reflow on a laptop board and after the reflow the board is warped in the area I did the reflow in, and now the laptop screen does not turn on at all when I put it back into the laptop. Original problem was the wifi (I did the reflow more or less as a test to see if i could fix it or not).
So I was wondering where I went wrong- could it be too much heat I used to cause warping? I had a pre heater on the bottom set to the max (250 C) which brought the top of the board to a temp of arround 80C. Then I used hot air nozzle to further heat the southbridge chipset on top. I had to set the temp to arround 450 C in order to get one of my thermal meters to show a temp of 270 C on the top of the board on the southbridge chipset. I let the chipset roast for about 2 minutes then I cut the heat down. I also used a no clean flux as I heated the board.
If that did not cause the warping maybe it was my holding jig? it has a spring loaded arm on it which puts pressure on the board. Maybe that is what caused it? I must admit when I loaded the part I did have it set very tight.
Also I noticed lots of residue from the no clean flux left behind, I cleaned it off and testes it again just incase that was causing a short out but even after cleaning it does not work (the laptop board). any ideas where I went wrong?
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