How to remove corrosion from color classic motherboard?

[habibrobert]

Any ideas on how to remove the corrosion from the legs of the various components on this motherboard? I've included a photo of what it looks like so far. To be honest, I can't tell if is corrosion of goo left over from leaky pram battery. I washed the motherbaoard twice already and still it wont go away. So I'm guessing it is corrosion? I don't want to use a wirebrush for fear of damaging the traces. Anyone have any ideas? Or should I just let it be? Will it get worse?

Thanks.

 

[Macdrone]

I use alcohol like already mentioned to you with a toothbrush.

 

[Charlieman]

Rust on aluminium legs?

 

[Macdrone]

Its bimetallic corrosion from moisture and age. I saw it alot before I ever saw it on a motherboard on aluminum superstructure ships. Salt usaully made it much worse much faster but just air moisture and leaky caps plus different meatals in vacinity with leaky caps and you get the same outcome.

 

[Charlieman]

Where does the iron originate?

 

[Macdrone]

Does not have to be iron but the screws for starters. Only has to be close not always intimate contact. Most of the frames are ferrous, seen plenty of regular rust on 128's and centris/quadras lately to know they have to be.

 

[habibrobert]

I've been using a tooth brush along with some rubbing alcohol, but to no avail, every time the alcohol dries up, I can see the corrosion again

 

[Macdrone]

I know uniserver uses a scraper of some sort to go in between legs of chips and the like. I have a scraper made out of soft wood and i do pretty well not going near traces. I also for harder stuff have used a soft wire brush and pulled in and away in straight lines for some bad stuff. Tooth picks may be a good cheap choice also. You may not need to remove it all if after recap it works, as long as its not conducting across, which a mulimeter you should be able to check if worried.

 

[TylerEss]

I'm not an expert, and I don't even play one on TV, but I do have years of experience as a talentless hack.

I've found that it doesn't seem to get any worse, if you remove the source of the problem (leaky capacitor goo) and get it nice and clean.

 

[nettrekker]

I've not tried this yet, and I won't do it to a precious apple board

until I've confirmed it on a scrap board:

50/50 mix of water, vinegar, and some salt, scrub with toothbrush.

Maybe one tablespoon of salt per cup of liquid? It's guesswork.

Rinse this with water, then rinse again with rubbing alcohol.

Use 91% alcohol, not the 50% or the green "witch hazel" stuff.

Then scrub with a mixture of water and baking soda.

A few tablespoons per cup? Again, guesswork.

For the final rinse, use generic bottled filtered water

instead of tap water, and not "spring" water which might

contain delicious trace minerals.

Microwave this water to get it near boiling.

Get the board bone-dry by "baking" it in the oven at very low

temperature, approx 125degrees F for a half hour.

That or place in front of a large fan for a day.

Water likes to bead up and hide in crevasses, less of a concern on

the larger-pitched parts on 1980's electronics, a real pain to achieve

bone-dry status on modern BGA based laptop motherboards.

If you want to skip a step, just make a 50/50 mix of vinegar and baking soda.

 

[trag]

I have not tried this, but in theory...

If the metal is oxidized, then coating it liberally with solder flux and then burning the rosin off with a soldering pencil, or ever a heat gun, should remove the oxides, maybe.

One of soldering rosin's purposes is to combine with oxygen and keep it out of and off of the metal that is being soldered.

http://amzn.com/B004RIF3BM

 

[uniserver]

Started using acetone it gets that nasty stuff off pretty good.

I use paper towel twisted up, try to use decent quality paper towel.

 

[James1095]

I usually use a little squirt of Deoxit, let it soak for a few minutes and then scrub it with a Magic Eraser (melamine foam) and it usually makes a big improvement. For more severe corrosion you can try a green scouring sponge but take care as it will scrape up the PCB. Dental type picks are good for getting nooks & crannies, you can get sets of those at tool shops.