introduction to my Macintosh SE/30 'hell toaster' projectby quirble, march 4 2025 CRTs are dangerous! reckless soldering is also dangerous! breathing in lead fumes from leaded solder and flux paste... time will tell if this is dangerous. I don't recommend it.years ago, some neighbors moved away. oh well, we didn't like them that much anyway. but we put on a nice facade of liking them so they gave us some stuff for free as "moving away gifts". one of those was a Macintosh SE/30 compact macintosh computer, produced from 1989 to 1991. these machines nowadays are infamous for an unprecedented amount of upgradability, both out of the box and through extensive 3rd party hardware modifications. with modifications like a new ROM, they can even support up to a maximum of 128mb of RAM! from a 1980s personal computer!!unfortunately mine never worked. 1980s/1990s macintoshes age less-than-gracefully; PRAM batteries explode, capacitors leak, chips die... most SE/30s experience at least 1 of these things, mine got two. THANKFULLY it was not the PRAM battery exploding, but unthankfully, it was still capacitors leaking and chips dying. thankfully i have a bunch of nice soldering equipment now (that i barely know how to use), so to finally try and make a dent in getting this project rolling, i thought i'd mess around a bit. recap it, maybe replace a chip or two that failed... what could go wrong???
this is an old image of the original symptom it had. no boot, and this weird screen. this is an EXTREMELY common failure type for SE/30s (commonly referred to as "Simasimac"), and it's supposedly extremely frustrating to actually pinpoint the issue. it can be as simple as "PRAM battery exploded and destroyed half the motherboard", to "one of your RAM chips failed", to something like "you need to check every single trace leading to the ROM SIMM for continuity because any one of them failing will cause this", and mostly is just answered by saying "yeah recap the motherboard". so you're telling me that this could be the result of ANY problem?? taking the motherboard out, and yep. there's capacitor gunk EVERYWHERE, and several of the legs of the chips on the "Extreme Problematic Zone" are gone. the "Extreme Problematic Zone", by the way, is all of THESE 16-pin SOIC chips, UA8 to UG8, which consist of various shiftregs and video multiplexers. this area oftentimes gets bombed the hardest by capacitors, my board not being an exception.
i had to remove all the old "yellow band" capacitors... which made a mess of my tweezers when the yellow bands MELTED ONTO THEM from the SMD rework heatgun i was using. and obviously because their legs were missing, i hot air'd some of the really problematic-looking Ux8 chips too, to replace them with new ones. unfortunately a LOT of damage had been done here, not just from my crappy handling of hot air but also from the extremely problematic capacitor goo. it almost seemed like some of the pads had disintegrated!! as for the others, the everpresent goo was stuck on basically every existing pad. aaaaand.... washing the board in the dishwasher did nothing. neither did scrubbing it up close with strong alcohol. the goo was stuck stuck. i eventually figured out that pouring an unbelievable amount of flux and lead solder onto the pad, and then scrubbing it as hard as possible with solder wick and high heat cleaned it effectively enough. but doing this process managed to eat EVEN MORE pads off the board!! (i told you this was a toaster from hell)
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