Any Tips for Repairing a Mangled PQFP?

[alxlab]

So I just noticed this on a Max ntosh Portable I was troubleshooting:

The SCC chip had been pushed so hard the pins on the sides are offset by 1 pin, broken traces, lifted traces and bent legs.

It amazingly still works in System 6.0.8 but 7 and up freezes on boot.

Any advice on how to proceed with repairing this without causing further damage?

 

[Elemenoh]

Oof that sucks. I might epoxy in little coper pads for the NC pins to anchor the chip down and then bodge the rest with really thin (maybe 40AWG wire. It'll take a lot of time and patience and still look like a mess after though.

 

[alxlab]

Correction. It's PLCC and not a PQFP. The pins were so bent I thought it was.

Just remove the chip and yeah...

That's a lot of missing and detached pads. One whole row of pins on the chip were broken too.

Will need a replacement chip. Maybe a PLCC socket would make the old chip usable but with so many pads missing trying ti remove the chip will probably rip the socket off the board.

 

[alxlab]

Well tried my best. Not too happy that I managed to put back some pads crooked, but it is what it is at this point.

The fuz is because I used tissue paper along with weight applied on top while curing to make sure the pad were pressed down properly.

I guess if I put a socket it would hide the ugliness.

 

[alxlab]

Here's the board with all the 0.10mm bodge wires .

Here's the final result! Great success! I ended up using a replacement chip with no socket.

All I can say is that I would recommend using JB Weld to fix pads. I was able to apply 300C for a fair amount of time with no pads detaching again.

 

[trag]

Beautiful work.

There was a thread somewhere in which a fellow basically rebuilt a hole in a board, or a fairly deep gouge, with a UV hardening solder mask.

That might have some application in this type of situation. https://www.amazon.com/dp/B01MUB4PJL/?coliid=I1KVVVH33K1WIW

I thought I had also saved a link to a usable UV light pen, but I don't seem to have it.

 

[Kai Robinson]

I think that might have been a IIfx board repair by @The House of Moth

 

[alxlab]

I had bought this particular set off of aliexpress for less than $7 CAD. The uv flash light was real garbage though.

View attachment 1693533781128.webp

Ended up buying the Darkbeam A300 UV flash light instead which was a looooooot better.

 

[alxlab]

I never knew this but it seems that the UV light tends to make flux residue show up as bright yellow.



It's useful when trying to clean off all the residue.