Re: Advice for a new BGA rework station owner please
Hi guys
I'm still managing to break stuff
I decided to remove a north bridge from an ASUS P5P43TD motherboard today
This one https://www.badcaps.net/forum/showthread.php?t=79353
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. 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.
So I used a hotter profile I created for LGA sockets and I cleanly removed the north bridge first time.
But 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)
I decided to clean the chip and the PCB anyway (for practice) and that went well with no further pads lifted. 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 also warmed the area of PCB (and the BGA) with my hot air station first as well.
I also noticed after cleaning that two pads on the PCB right next to the two lifted ones were dull plain matt grey. I scratched them very lightly with a needle point and the grey whatever-it-was rubbed off leaving shiny pads
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 know I need to post some pics, I'll grab some tomorrow or on Monday.
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)
Also can I ask - are you folks using any flux during BGA removal?
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. Maybe that is my problem?
Hi guys
I'm still managing to break stuff
I decided to remove a north bridge from an ASUS P5P43TD motherboard today
This one https://www.badcaps.net/forum/showthread.php?t=79353
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. 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.
So I used a hotter profile I created for LGA sockets and I cleanly removed the north bridge first time.
But 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)
I decided to clean the chip and the PCB anyway (for practice) and that went well with no further pads lifted. 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 also warmed the area of PCB (and the BGA) with my hot air station first as well.
I also noticed after cleaning that two pads on the PCB right next to the two lifted ones were dull plain matt grey. I scratched them very lightly with a needle point and the grey whatever-it-was rubbed off leaving shiny pads
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 know I need to post some pics, I'll grab some tomorrow or on Monday.
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)
Also can I ask - are you folks using any flux during BGA removal?
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. Maybe that is my problem?
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