Need advice. PCB tracks (See my PCB pic)

[Jonk]

Edit:

Okay, sorry. Here's a better pic. In a post awhile ago I expressed my concern over my own brutalizing of my PCB on a couple of my PM1000 strips.

A couple reasons for it: Cheap soldering needle that wasn't hot/fast enough. Also, I think in some instances I may have "over-cleaned" the flux off. I used 99 percent alchohol, but I think it may have started to eat at the PCB tracks too much.

Regardless of what you guys say, these channels still sound awesome. And I'm totally going to use them. I'm just wondering how far I went in terms of really doing harm.

So, you'll see that the green tracks are eaten away a bit at the edges, and the gold colored track is showing from underneath. What do you guys think of this? I mean, the connection is still there right? (They still sound good to me, but I still wanna know) Is the green top layer more of a protective coating and the gold layer underneath is where the real connections are?

And advice or comments are welcome.

[r0ck1r0ck2]

what's the problem jonky?

[tINY]

Looks like a late 70's discrete design using a single sided PCB.....




-tINY

[ulysses]

It's a Yamaha PM1000 input module, right?

[Cojo]

It's a trick question...

[r0ck1r0ck2]

yep that your standard army issue pm1000..

oooohh this is like waiting for the mystery to develope...

[Jonk]

Okay,
Posted a better pic. See above.

[ulysses]

That green stuff is the "solder mask" layer, which is a conformal coating that protects the circuit board. It's an even polymer coating applied to the entire circuitboard except for the pads around the holes. It is only present in places where you don't actually do any soldering, so if you're careful soldering then you shouldn't mess it up too much. But even if you do, it's not going to wreck your board. The copper traces underneath are not going to be affected by alcohol. True, if the conformal coating is removed it will expose the copper to air which will slowly corrode it but you're talking about a process of decades in most dry studio conditions. In other words, be more careful soldering, but don't worry about it. Use actual flux remover rather than alcohol so you can remove the flux quickly without scrubbing off the green plastic soldermask layer.

In summary, your alcohol did not "eat away" the traces at all. The protective layer is good to leave intact, but don't sweat it.

[tINY]

You should use a little flux when you are desoldering the contacts. Then use solderwick to remove the extra solder, clean with de-fluxer, and then resolder.

To preserve the vintage sound, you should find freon PCB de-fluxer (it works better anyway...)




-tINY

[Jonk]

Okay,

Cool. That's kind of what I was imagining was going on. I had no idea there was even a deflux product. I'll have to look into that.

One more question, just for reference, I've heard of people adding flux before, but I don't quite understand this. I thought the flux was in the solder, and then you have to clean it off when you've soldered a new connection because it more or less comes to the surface and spills over the sides of a joint when you heat up the solder.

Is there a flux-less solder or something? And in that case people are adding their own flux? This seems like an extra step that could kind of be a pain in the ass.

What's the theory here?

[ulysses]

Flux is used to prevent oxidation of the solder while it's melted. It basically inhibits a chemical reaction from taking place. Most solder has a flux core, a tiny thread of solder running through the center of it so that you always get an appropriate amount of flux for the amount of solder you're using. You can buy solder without flux but it's difficult to work with.
After the board is finished being soldered at the factory, all of the flux is generally removed from the solder joints. So when you go to make a repair or replace a component, it's hard to get the solder to flow again unless you add a little more flux. It can be done, but the solder flows MUCH better if there's a little bit of flux. That's why it's sometimes helpful to add a little bit of new solder when you're trying to desolder something - it's not the additional solder that's helping, it's the flux in its core. But you can buy flux by itself (I have a can of it that looks like a can of shoe polish, and it's lasting me years). By putting a little bit of paste flux on the solder joint before you try to rework it, you end up not needing so much heat or time to get the solder to flow. It saves a lot of abuse on the circuitboard. But when you're done, you generally want to clean the new flux off of the new solder as well. So you add a little flux, desolder the pin, remove and replace the component, resolder it. When you're done working on the board, then you deflux it.