I Need Re-balling Help........, ACHI IR PRO SC advise and tips needed Options

[Skeeterbite]

I tried to do a re ball on my first PS3 fat, did not turn out good.......

I just got my new ACHI IR PRO SC and it has 2 preset patterns.

I ran preset #2 for lead-free solder and after the alarm I could not remove the chip.
So I ran preset #2 for a second time, and again, could not remove the chip.

I set up another pattern a little higher temp and longer dwell time on the final temp, and was able to get the chip off, BUT it had blistered (destroyed) the chip and board......

Correct me if Im wrong but I think the RSX plate on top of the GPU chip is the reason that the #2 preset did not work.

I have taken that RSX plate off of 2 other GPU chips in the past to be able to do reflows properly, one of the plates came off nicely but the other came off with 1 of the 4 black chips still attached to it. (broke the chip)

The thermal paste under the plate is always beyond dry and useless, it is rock hard and very difficult to get off. It is restricting heat transfer from the chip to the plate, therefore restricting heat transfer from the plate the the heat sync.

So.... couple of questions:

Is there a way to remove that plate without destroying the chip so I can heat the chip directly?

Can anyone help me out with the pattern for the playstations? (r1,l1,d1, r2,l2,d2, ect.....)

[herman69]

Bit of a late reply, but try this....

LEAD FREE SOLDER - (Top Heater 32mm above board - Bottom temp 260c with TC just above heatplates)
R1 85*C - 180 seconds
R2 140*C - 45 seconds
R3 170*C - 45 seconds
R4 225*C - 45 seconds

LEADED SOLDER - (Top Heater 32mm above board - Bottom temp 260c with TC just above heatplates)
R1 85*C - 180 seconds
R2 150*C - 55 seconds
R3 185 *C- 55 seconds

That's with the thermocouple 2mm away from the bottom right corner of the GPU.