Long live thrift stores....

[Topcat]

I was told that the local thrift shop had a bunch of computers for sale really cheap......reluctantly I went and checked it out...... I know now why I was reluctant, there was a pile of beat to shit emachines systems and a few banged up dells, all of which was s370, socket A, and a few 478 systems, nothing too terribly recent....most all beat to hell and overpriced.

I guess there's a white sheep hiding amongst every herd of black sheep... I walked around the shelf to the other side, low-n-behold, there's a 20" Imac sitting there, KB, mouse, and all. Sticker on it says "runs for 5 minutes then shuts down, $10.00" For 10 bucks, what the hell. I took it up front, paid and left. Sure enough, I get it home, and we all know what was ailing it.

This one is going to be part of an experiment. Details later.

[ratdude747]

Re: Long live thrift stores....

if anyone can fix it you can! lucky you :jealous:

[Junk Parts]

Re: Long live thrift stores....

After you make it work again you know what you may need to do....LOL Cut the case all to hell and cover it with fans.

[seanc]

Re: Long live thrift stores....

Bonus points if you explore the PSU.
I still have a dead PSU I wasn't able to fix, here.

[Topcat]

Re: Long live thrift stores....

Bonus points if you explore the PSU.
I still have a dead PSU I wasn't able to fix, here.

Yes, that's standard procedure around here. PSU gets recapped when the logic board does. I have some more G5's on the way for some experiments, which will be released later....this one was just a lucky find.... I havent recapped it yet, I'm waiting for some goodies to arrive.

[stj]

Re: Long live thrift stores....

i did one of those,

the mobo is a bitch to desolder from - i have never seen a pcb soak up heat like those!

[Topcat]

Re: Long live thrift stores....

i did one of those,

the mobo is a bitch to desolder from - i have never seen a pcb soak up heat like those!

Try stuffing polymer caps with fatter leads into those tiny holes.... I've found I always have to turn up the heat on the soldering station to easily reflow the solder. It takes longer to get one apart than it does to recap it.

[Colt45ws]

Re: Long live thrift stores....

Im not a apple fan but for $10 I would've taken it too!

[severach]

Re: Long live thrift stores....

the mobo is a bitch to desolder from - i have never seen a pcb soak up heat like those!

Yep. The Hakko 808 is able to take the caps out but is unable to clear many of the holes even with the help of an SMD heater. That's the only board yet I've needed to drill to remove the solder.

The new caps were soldered with tin/lead.

[Topcat]

Re: Long live thrift stores....

^
NEVER drill out a through hole on a multi-layer PCB!! If there's a plane in the layers connected to the tube in the through hole, and the hole is drilled out, then the contact will be destroyed, as well as the rest of the board. A good pick and a hot iron, iMac boards aren't any more difficult than anything else.

[Dgtech]

Re: Long live thrift stores....

You got me ready to do some thrift store hopping!!! I just lucked out last week when I saw an ad on CL for an oscilloscope. This guy is selling like 20 used tube O'scopes (30 Mhz) for $90 each. I glanced around the room and I saw a portable Tektronics TDS 1002 Digital storage scope and I asked him, " how much for the little one" he told me $30. LOL. It was the last portable one he had. That guy had no idea what he had. He was selling off the school's remaining electronics lab equipment.

Keep looking for deals, they are out there!!!

[severach]

Re: Long live thrift stores....

NEVER drill out a through hole on a multi-layer PCB!!

Not only do I have the right size drills, the Apple solder quality is so poor on that board that the solder doesn't wick to the component side. This allows perfect alignment which eliminates the danger of slicing the plate through.

I don't drill unless I need to. I was able to clear many of the holes with my guns but a few wouldn't clear without the drill and since this board is a regular customer I wasn't going to reassemble that low quality Apple product with anything less than 100% tin lead solder.

Next you're going to tell me that I'm in danger of removing the plate through by using a gas torch file to clean the arc soot from laptop power jack holes.

[NxB]

Re: Long live thrift stores....

Drill press with tiny bits could do it.

[Topcat]

Re: Long live thrift stores....

Not only do I have the right size drills, the Apple solder quality is so poor on that board that the solder doesn't wick to the component side. This allows perfect alignment which eliminates the danger of slicing the plate through.

I don't drill unless I need to. I was able to clear many of the holes with my guns but a few wouldn't clear without the drill and since this board is a regular customer I wasn't going to reassemble that low quality Apple product with anything less than 100% tin lead solder.

Next you're going to tell me that I'm in danger of removing the plate through by using a gas torch file to clean the arc soot from laptop power jack holes.

I'm not telling you anything, do yours the way you want, it's not my board and I really don't care. However, I've seen more than a few people destroy their board doing this, which is why I don't condone it, especially for a novice. Most of the members of this site are indeed novices when it comes to component level repair, which is why they came here in the first place. Its definitely not the recommended process to clear a through hole, especially when something as simple as a hotter iron and a cheap dentist's pick will do the same thing with zero risk.

[willawake]

Re: Long live thrift stores....

the Apple solder quality is so poor on that board that the solder doesn't wick to the component side

uuh work both sides then?

[Topcat]

Re: Long live thrift stores....

^
Or use a pick. Clears the holes in less than 3 seconds per hole, no drilling required....

[kc8adu]

Re: Long live thrift stores....

^
NEVER drill out a through hole on a multi-layer PCB!! If there's a plane in the layers connected to the tube in the through hole, and the hole is drilled out, then the contact will be destroyed, as well as the rest of the board. A good pick and a hot iron, iMac boards aren't any more difficult than anything else.

+1
got a ton of billable hours on a irreplaceable industrial board someone tried that on.
i have never seen someone as happy as the owner of that machine when i flipped the breaker and the screen lit up with the japanese comic faces.it was some custom one off machine made by hitach-seiki for a .gov contract.
the moron who drilled out a bunch of holes not only got fired but i bet he also got the bill.
he made a real mess of that board!