I'm attempting to do the RGB mod for the NES, but I'm running into a few problems removing the original PPU.
I have a desoldering tool that works pretty well, about 75% of the time. It's basically like a soldering iron with a hollow tip and it uses suction to remove the solder. The problem is that sometimes the solder is down inside the holes and it seems to be nearly impossible to get out.
I was able to remove the original PPU, but a few of the holes are partially clogged. I had tried a couple of things to get them cleaned out, but it wasn't really working all that well. Basically what I was trying was to stick a thin piece of metal (chip pin, staple, etc.) in the hole and heat it. The soldering iron I was using at the time has a rather large chisel tip so it was a little tricky. I was able to get the solder to melt inside the hole, but I couldn't get it all cleaned out.
So then I had the idea that if I could find a soldering iron with a small enough tip I could just stick it inside the hole and push the solder out. It seemed like a good idea to me at the time...
So I went to a local electronics store and found a $3 iron with a small conical tip. It looks like about 0.8 mm or so. They had smaller tips at the store, but they didn't look like they would fit the iron I already had nor would they fit the the cheap one I found. So anyways, I bought the cheap iron and found that the tip is just small enough to fit a little ways inside the holes on the motherboard. I thought, "Sweet, this just might work."
So I heat up the iron, stick it down inside the hole...what's that burning smell?!! All inside the hole and just around it is all black now and it smells terrible. I'm thinking it must be beyond hope of recovery now.
Sorry for the long backstory...my main question is--how do you remove solder from inside the pinholes without frying the board?