Lately i have been getting in more and more consoles where customers have tried to fix it themselves. Either bolt modding or heatgunning.
The chances of me repairing them when they have been worked on previously reduces greatly. The last 2 i got in where bolt modded with washers and such. Flowing them did not work, so i proceeded to lift the chip to ball em. After lifting several pads were missing. Both boards pads lifted, even though i had a clean lift.
The cause is warpage by using bolt mods. Sometimes chips are dead, because of too much heat with heat guns.
Now dont get me wrong, some people get their consoles to work with these x clamp mods. The reason they work is because they apply pressure on the chip so that it makes better contact with the board. However this is FORCED contact and causes warpage over time.
The faults with heatgunning lie with inconsistency in temperatures, uneven heating or too much heat. However i know some who do great with work with the heat guns, of course they ruined quite a few boards learning but eventually they figured out how high and how long to heat it up.
Those who actually properly repair consoles have spend a few hundred to a few thousand on the PROPER equipment. We have excellent success rates and rarely experiences failures unless of course we receive previously worked on consoles.
There are several different x clamp methods. The hybrid being the most talked about. I am sure some of them work really well. But the actual cause is not being fixed, its merely being covered up.
Think of duct taping a leaking pipe vs welding it. The duct tape will work but obviously a clean weld is the best or even replacing the pipe.
Regarding x clamps after a reflow or reball. A lot of techs do this to keep the repair lasting, but proper spacing and washer size comes into play. Not every washer is the same. Some might be .2mm off, others .05mm off. This does make a difference however, either not enough pressure is applied or too much pressure is applied to the chip. I personally do not use x clamps after my repair.
I do however turn the fans on high. Apply fresh thermal compound and tell the customer to keep it cool as possible.
Some may agree some may disagree. But to each his own, i just wanted to inform you all of my experiences in repairing consoles.