The Mac SE/30 From Hell (Or: How NOT to Solder!)

d0pefish

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This one's for our tokyoracer :) <3

So, tokyoracer had received a Macintosh SE/30 that "didn't work", and threw it in the post for me to look at along with some other fun gear. I've never been acquainted with classic 68k Macs before, and I thought it'd be fun to see if I could help find what was wrong. :)

Well, put it this way - it didn't bloody take very long to work that one out. :roll:

Basically, classic Macs suffer capacitor plague just like our beloved Amigas, and replacing the motherboard capacitors is a common repair.

So, of course a previous owner reckoned it'd be a great idea to get to work with a fistful of cheap Chinese capacitors and.. going by the "work" you're about to see, a plumbing soldering iron. :Doh:

Check this out.

Not even attached!


*shudder*... :nono:


Hang on... what the HELL? :wooha: :nono:


Seriously, what the hell is up with that trace?


I'll just give that cap a little push and... Oh teh NOES!!!! :eek:veractor:


The trace is just...floating and he's tried to solder it to the leg! :sigh: The pad is obviously missing :(

So, the first thing I did was undo this awful "repair", and removed all the capacitors. I noticed that on just about every pad, he'd left the legs of the old original capacitors behind! This means he's just gone round snapping them off!

Seriously guys, I hope none of you ever do this. You're going to take a pad and probably a trace with it by doing that, just like this guy. You must have patience, the right equipment, and desolder the components with care! :( This is not a task for dad's 200W garage soldering iron! (n)

Also, he'd tried to solder the new caps onto the pads without any cleaning up! There was residue and electrolyte everywhere, and the pads were still tarnished and coated in corrosion when he'd attempted to do the fix.

Lots of flux, solder wick, Isopropyl alcohol, and a fibreglass PCB pen were the order of the day to sort this mess out. :D

When Chris gave me this board, and I described these issues, he wasn't very optimistic about a fix being possible, but I said I'd do everything I could.

I wanted to get this Mac working. :)

So, here's where that trace went - under one of the Sony chips. I removed the chips and discovered more horrors underneath.


After a cleanup, and a look under the second chip:


The chips also received a good scrub and the legs were cleaned up. Sockets were installed in their place, along with a wire to bridge the broken trace - lucky that that was the only broken connection! :D

New capacitors in place (I used tantalum parts like the 68k Mac Wiki recommends, and instead of fairly average axial capacitors, I decided to adapt my favorite Panasonics in their place with some heatshrink to protect their legs).


And ready for testing! It was too costly and inconvenient for Chris to package up the rest of the Mac (he says they weigh more than you'd think with their CRTs!) so I used a spare ATX PSU to apply the correct voltages to the board and listen for signs of life from the speaker.


The result?
IT WORKS! :drinkin::arms:pint::thumbsup2::thumbsup2:
Initially I got the BONG followed by the "Chimes of Doom", but this was because I hadn't populated enough memory banks. :) Either way, according to Chris it had never bonged before and never booted, so this was very exciting! :)

I have a video of me showing the Mac powering up for the first time after taking care of the damage - I will upload it very soon :)

I called Chris last night, and the conversation started something like this:

*ring...* *ring...*
Chris: Alright chap?
Me: Yeah dude! I gotta show you something. Listen to this!
*BONG*
Chris: OMFG...


So, hopefully we can see this cool little Mac booting up properly one day, once it's back in Chris' posession and he can reassemble it.

Cheers guys! (y)
 
Looks like a great job! (y)

A shame I trew a working one out a couple of months ago (no space)

How do you lift a track, is that by exessive heat?
 
Thanks guys :)

Yes, a combination of too much heat, corrosion from the leaked electrolyte, and the act of PULLING the component off the board. If you have to pull, the solder isn't fully melted and you will be stressing the pad.

Surface mount components should never have to be pulled off with force - once you heat the solder with a hot-air rework tool, the components can simply be picked up with tweezers :)
 
I love these stories, they really give me a warm glow inside as our members help each other and more classic computers are given a new lease of life! This is what Amibay is all about!

:grouphug:
 
Thanks :)

I'm glad that you enjoyed the post.
I really enjoy servicing old/dead machines, I was glowing when I heard that startup sound last night! Made the whole job worthwhile for sure! :D
 
Aww, way cool. I've gotta get my SE/30 working sometime...no horrors like that, thank God, just needs a hard drive and a recapped logic board.
 
Uff amazing but it's look better from ps3 board or mobile phones who i sometimes recived .Somebody ,using stiupid Youtube solution, try heat IC using heater for remove old paint!
 
Freakin' awesome!!!

The old pictures just dont do it justice, the board was a s****y mess. D0pefish's magicical soldering and electronic god like skills has managed to do the impossible and make her alive again! Im totally lost for words!!! :eek:

A great little computer rescued from certain death, never knew she would come round like this, thank you so much D. :D

:arms:arms:arms:arms:arms:arms
 
Hi Zaxon!

Nice to see you on here mate - my UltraSatan is still working great! (y)

Yes, sadly amateur attempts to repair things can often make matters much worse. :( Those garage/paint heat-guns are lethal!

@tokyoracer:
Aw, shucks dude :) Welcome any time, I'm glad to have helped mate :D
 
I will just make a note that I didn't attempt these bodge repairs, it's how I received the board. :p
 
The capacitor leakage is not corrosive as a battery leak, but the spillage is "good" enough to melt the adhesive who held copper traces in place.

My personal advice is always wash a board with capacitor leakage prior to any attempt of repair.

@Dopefish: excellently done, mate.

And thanks for teh pr0n!:)
 
/indignant

My Black & Decker heat gun is my rework station and I've not had any problems reflowing 48-pin TSOPS and other SMD stuff; it does take some practice and skill to use a heat gun properly, though.

@ Zaxon & d0pefish

I know exactly what you mean about Youtube though; a little knowledge is a dangerous thing when it comes to soldering and reflowing.....:roll:

Hmm.. a toaster oven or a hot air rework station for rework? That's a tough call to make.....:LOL:
 
What does reflowing mean?? :oops:

Ive got one of these Macs which whines when i switch it on, Ive been told the caps need replacing.
 
I've fixed laptops and graphics cards in my regular kitchen oven, but this was before I invested in my station :)

Not knocking the technique at all - it can work! (y) You understand what we're getting at anyway :)

@Taj:
Reflowing is "simply" heating solder until it melts into liquid form but without actually removing the component - the technique is used to fix solder which is fractured or not reliably attached to a joint, but not bad enough to require a complete desolder/resolder.

Your typical Xbox 360 fix, basically :)

There is some technique to it though, accidents can happen if you take a ham-fisted approach :LOL:
 
Ahh, makes sense to me now, thanks Dale!

Done the 360 fix a few times too ;)
 
OK, so your hardware pr0n has inspired me to open my old Mac up! Firstly, its a Mac Classic 2, and secondly, the motherboard looks totally different from the pics you have posted :blink:

I have posted a pic below, when I switch it on it makes a whining noise, which upon searching the net seems to be leaking capacitors, but they look OK to me??:blink:

Any ideas?
 

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