It's like some sort of oxide that rejects flux. I know i isn't very exciting) you will see some of those dull grey pads I was talking about on the BGA and PCB which I have to scrape to clean them up. Please could you advise on that?Īlso if you watch the video through (please. I'm not sure I am cleaning the PCB to the standard required for reballing and replacing the BGA.
Sorry there is no audio on these - I'm trying some new recording software on my PC rather than using my phone and I need to get a microphone. Here are a couple of videos of the inspection before clean up I've posted some pics of the profile during soak phase and just at the moment the profile completed I used a lower temperature profile and it came off without damage to the BGA or motherboard. I decided to remove the South Bridge from the ASUS P5P45TD that I wrecked last week trying to remove the North Bridge I'm not using any but I do have some Topnik liquid flux I could possibly get to run under the edges of the BGA before removal. I'm not sure if the problem was too much heat during removal of the BGA, or if there was a problem with some sort of corrosion/damage on those pads anyway (bear in mind the motherboard did not work)Īlso can I ask - are you folks using any flux during BGA removal? I know I need to post some pics, I'll grab some tomorrow or on Monday.
So two pads lifted from the PCB in one corner, all others (and all pads on the BGA) were good = not quite a success LoL I scratched them very lightly with a needle point and the grey whatever-it-was rubbed off leaving shiny pads I also noticed after cleaning that two pads on the PCB right next to the two lifted ones were dull plain matt grey.
I also warmed the area of PCB (and the BGA) with my hot air station first as well. Following previous advice from here I was using my T12 with BC3 tip at the slightly lower temp of 320C and small 1-2cm strips of braid cut from the reel this time. I decided to clean the chip and the PCB anyway (for practice) and that went well with no further pads lifted. So I used a hotter profile I created for LGA sockets and I cleanly removed the north bridge first time.īut examining it under the microscope before cleaning I could see that two pads right on one corner of the BGA had come off the PCB (and they were still stuck to the BGA) 230-240C on the PCB temp probe (260-265C final nozzle temperature) just doesn't seem to do it even though you would think the solder should have melted already. One thing I found out last week is I have to get quite a bit of heat into ATX motherboards for quite some time to remove large components (such as CPU sockets) My temperature probe right next to the chip has to get up to a good 260C-270C for 20-30 seconds (which requires an upper and lower nozzle temperature up to 285C for the last 15 seconds) or they don't come off. I decided to remove a north bridge from an ASUS P5P43TD motherboard today