Damage from desoldering?

tonyarbisi

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I am pretty new to working on pcbs. I had an amp I saw start smoking on a Double Dragon board and the sound quit working. So I ordered a new one and am working to replace. After removing the component, the board looks like this. I think the bottom side looks ok, but the top side especially on the right looked kind of damaged. Did I damage it or is it just oxidized and burnt flux? I have tried cleaning with flux cleanr and alcohol and a toothbrush. But it doesn't seem to get cleaned off. If damaged, thoughts on repair? Thanks for any help.
 

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Looks like you pulled lotsa pads on the top side there. The only real damaged traces are on the top side, looks like pin 2 hooks up to that ground plane.

For the future, make sure you remove all solder, and if it feels stuck reflow and try again. If you know the part is bad and you are struggling with your equipment, cutting the pins also and removing the pins one at a time helps a lot.
 
Yikes. Please add "NSFW" in the title.

But, really, soldering/desoldering is an acquired skill that comes with lots of practice and time.
Also you need the correct equipment. And patience. More heat (and hold-down pressure) is not necessarily a good idea as you seem to have discovered. :(

What tool(s) did you use here?
 
Uggg, was what I was thinking. I just used a soldering iron, solder, flux and desoldering braid. Thought it would be pretty easy, but it didn't seem to want to come out all the way. I added solder to them and then tried to get them out by trying to heat them all enough at once to remove, but I couldn't get them all heated at once. Some moved but couldn't get them all. So ended up cutting the pins and doing each by themselves. Looks like I needed to practice my desoldering some more on some scrap boards. Yeah was guessing I put too much heat and pressure on it trying to get things moving. :confused: Thank you all for the confirmation. Looks like I need to learn some pad repair.
 
Yikes. Please add "NSFW" in the title.

But, really, soldering/desoldering is an acquired skill that comes with lots of practice and time.
Also you need the correct equipment. And patience. More heat (and hold-down pressure) is not necessarily a good idea as you seem to have discovered. :(

What tool(s) did you use here?
What does NSFW mean?
 
You may want to consider a desolder gun of some sorts. Even a simple one like this:
https://a.co/d/7KHnkcd
If you don't want to spend alot. It will do a way better job than a soldering iron and braid.
Otherwise you could spend the money on a Hakko gun or a knock off version of a hakko.
 
if you all look close the through hole plating is still intact. I always do continuity tests on chips/parts I remove on the solder pads top and bottom. they usually always beep suggesting the through hole plating is still intact.

this was from a Gravitar board the other day where the 6012 was apparently socketed by some hillbilly that had no business doing what they did (see picture). the socket was so junk you could just lift the chip out with your fingers, so that had to go and this is what I was left with. I'm honestly intrigued it worked like this with all the traces burned off the pads. this was an involved patch process but it now works. sidenote: I'm thankful I don't see this hack nonsense daily anymore.

440184907_430443662910632_7674112870618980768_n.jpg

in other words your patch operation is small fries by comparison. sand/scrape open a portion of the mask (red box) and feed a wire strand (the line going to the hole) up through the hole from the solder/under side and fold it over against the area you sanded and solder the strand into the sanded area. install your new part and solder accordingly with the wire strand running parallel to the amp leg. test that your ground pin is making contact with the amp leg. #profit #FunctionalityOverAesthetics

20240504_143312.jpg
 
when you braided it did you use it on the top side too the lift the solder from the top. to resolder new chips the pads must be polished so they have no oxide on them so that the solder will flow and connect on both sides otherwise top pads might not be connected to legs
 
S-993a is a good middle-ground if you don't want to invest in a Hakko but hate those manual pop-type vacuum suckers. Paid $80 for one a few years back on banggood and it's been rock solid.
 
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