Compu's Conquests

[CC_333]

I hate to say it, but unless you're good at finding and repairing rotted traces and components, that board is probably doomed.

That being said, it looks like it *might* be salvageable with much work.

At least you got some good RAM!

c

 

[CompuNurd]

What's a good way to clean this up?

 

[TheWhiteFalcon]

Bathe it in vinegar and lightly scrub with a toothbrush. Remove any socketed chips or SIMMs (if the 030 is socketed it should be gold pinned and okay to leave), then rinse with regular water, then rinse again with distilled water. Then get it dry (compressed air, light 100 degree bake in the oven).

 

[Unknown_K]

Since it is winter and low humidity it should dry out in a day or two without baking. I never bake the boards I wash (soap and water) and they are all dry in a couple days.

 

[CompuNurd]

I use an air compressor then let them dry for half an hour.

 

[CompuNurd]

It's starting to look more hopeful than what I began with.



The question now is how to remove the trace amounts of corrosion? Acetone didn't help much.



And if I should even bother trying to restore the frame... Looks like it's going straight to the scrapyard. I will probably be buying a parts Mac SE to use for the metal frame.

 

[unity]

Sorry, but I can not agree with letting a board just sit. It needs some heat. Water in contact will metals causes corrosion. The water needs to be pulled out ASAP. I use a hairdryer initially then hang in front of a space heater. The heat sink hoot on the boards happen to hand right on the heater handle in front. Occasionally I shake the board and maybe take the hairdryer to it to blow out water from under stuff. Of course compressed air is best.

As good as that look though, I still think that board is a lost cause.

 

[CompuNurd]

Why does it look like a lost cause? Too corroded?

It at least boots to the simasimac screen, so it works to some degree..?

 

[unity]

Well I would LOVE to be proved wrong in my thoughts, so dont give up! But the vias in the SE/30, like the portable, seem sensitive to issues/corrosion. And my fear is that there is some corrosions, via the vias, into the other layers.

 

[CompuNurd]

How do I check for this?

 

[unity]

Continuity is the only way. Given the level of corrosion, thats a lot of checking! But really first things first. At this point is pretty much re-cap ready. I would start there, the caps. And go from there. IF you are lucky, the vias were all soldered shut. From what I see, the vast majority were. But I see a few holes, those are the ones that would concern me the most.

 

[CompuNurd]

Even if I get it working, the corrosion on the pins concerns me. Would it keep eating away at the pins until the chip fell off or didn't make electrical connection?

 

[unity]

Those pins are not too bad looking. I have seen worse that work fine. Just clean it well to remove the battery residue. You probably are already at that point, but a cleaning after the re-cap is always a good idea. You may have to get creative and somehow clean the contacts though with something. What I am not sure since they are hard to get to down in that holder. Maybe fold some fine grit sand paper and work it back and forth gently a couple times? If you try that, cleaning after would be a must to remove metal particles.

 

[CompuNurd]

I have a hot air station. I might pull up one or two of the chips and see if I can scrape or sand the corrosion off.

 

[unity]

I see you have another SE/30. Not sure if you tried, but if that system is good you may want to try this board that that boards ROM/RAM in this thing, just for giggles. There may be a power issue in this machine causing the problem. I have seen stranger things happen, especially with several Classics I worked on.

Just a though. Anytime I have multiple machines, I like to try parts on others to rule stuff out.

 

[CompuNurd]

I'll try that out tomorrow and report back.

Thanks!

 

[unity]

Its a long shot, but I told Uniserver once about two SE/30 boards I had. One was trashed, totally. But it worked fine. Another looked new and was dead, nothing I could do to save it.

 

[360alaska]

May just a 2000 grit sandpaper? And after that flux and tin and the flux should push the contamination outward.

 

[Elfen]

Even if I get it working, the corrosion on the pins concerns me. Would it keep eating away at the pins until the chip fell off or didn't make electrical connection?

Continuity is the only way. Given the level of corrosion, thats a lot of checking! But really first things first. At this point is pretty much re-cap ready. I would start there, the caps. And go from there. IF you are lucky, the vias were all soldered shut. From what I see, the vast majority were. But I see a few holes, those are the ones that would concern me the most.

That "Corrosion" is the battery acid itself and not the logic board. Logic boards use copper so corrosion there would be green or blue green in color, not red. You should be able to remove the battery acid and then then check for chewed up lines/traces. And of course - wash it (again!) to remove cap goo with ammonia, acetone, alcohol, so on. You know the routine.

If it can be brought back to life, you can do it. It just going to take a lot of time to get it done. But I figure like this - if you're a Mars colonist and your SE\30 board crapped out, you have no choice but to get it fixed no matter what since a new SE\30 shipped from earth is going to take 2 years to get to you on Mars!

 

[CompuNurd]

I never did bathe it in vinegar, but tried scrubbing contacts with acetone. Should I try vinegar next?