Finally re-capped my SE/30 (pics, and first power-on movie)

[RWallmow]

Been so much talk of bad caps and re-capping lately, I decided to re-cap my SE/30.

Old caps were so bad they almost fell off the board, very light pull and they came right off cold, I didn't even have to desolder them.

Mind you I am not very good at surface mount soldering, and all I had on hand was radial-lead capacitors, so it is not going to win any best of show awards, but she runs like the day she was new ;-)

re-capped board: pile-o-blown-caps: Closeup of C2-C7:

 

[RickNel]

Working = good!

I just did my first re-cap on a llsi. I was a bit nervous about SMD, but I found black solid tantalums that matched others on the board. The key was to use solder paste, and tweezers to hold the cap in position while flowing the first side, then firm pressure on top to settle it while flowing the second side. A few slightly crooked to the eye, but all contacts OK and tight AFAIK.

Rick

 

[RWallmow]

Working = good!

I just did my first re-cap on a llsi. I was a bit nervous about SMD, but I found black solid tantalums that matched others on the board. The key was to use solder paste, and tweezers to hold the cap in position while flowing the first side, then firm pressure on top to settle it while flowing the second side. A few slightly crooked to the eye, but all contacts OK and tight AFAIK.

Rick

Yeah, I was nervous about the SMD work on this, more nervous about removing old than I was about soldering the new just because I heard horror stories about people lifting traces removing the old caps, but mine were so rotten that they pulled right up without any force, I am literally surprised they hadn't fallen off on their own.

I had re-capped another SE/30 about a decade ago, but had extensive help and guidance from a friend who did SMD soldering for his job, so he knew his stuff, and did most the removal of the old for me.


On another note, I tested the SE/30 further since the video, and all ill effects are gone, it is truly working 100%. The bad caps had affected the SWIM chip operation, floppy read/write was erratic, most of the time not recognizing disks were inserted, now sees all the floppies I have inserted into it.

 

[DOS lives on!!]

Well done on it! Another computer added to the "working" list. Once those caps go corrupt, they sure turn problematic.

I recapped my first motherboard a few days ago. Thing's been sitting around for over five years.
Thanks for the advice on the use of flux. The first soldering, I didn't use flux. Bad mistake that was, and the motherboard wouldn't start up. After fluxing the leads, the solder flowed right into the hole.

 

[RWallmow]

Well done on it! Another computer added to the "working" list. Once those caps go corrupt, they sure turn problematic.

I recapped my first motherboard a few days ago. Thing's been sitting around for over five years.
Thanks for the advice on the use of flux. The first soldering, I didn't use flux. Bad mistake that was, and the motherboard wouldn't start up. After fluxing the leads, the solder flowed right into the hole.

Yeah, I used plenty of flux, probably too much, but it worked well enough, didn't have to swear at it too much ;-)

All the burnt looking areas around the solder joints are excess burnt flux, I cleaned it up a bit more after the photos were taken.

 

[Hatta]

Flux is weird. When I use flux, sometimes I'll get a joint that just won't wet properly. Clean off all the flux and it wets fine. But then if I don't use flux, I'll get a joint that just won't wet properly. And then I add flux and it wets fine.

 

[Stone]

DUH, flux core solder -- it's a no-brainer.

 

[RWallmow]

Flux is weird. When I use flux, sometimes I'll get a joint that just won't wet properly. Clean off all the flux and it wets fine. But then if I don't use flux, I'll get a joint that just won't wet properly. And then I add flux and it wets fine.

Yeah, some connections take more than one attempt, there was one that was heavily corroded on this SE/30 from the leaked cap, took a few attempts, and more cleaning, to get it to wet.

DUH, flux core solder -- it's a no-brainer.

I still like dipping the cap leads into some flux, make it "stick" quicker, less time with the heat on it, at least in my experience. Plus with through the hole leads, it pretty much ensures that it will wick some solder up into the holes better.