Soldering technique - best practices

The brown residue is of course the flux.
Different brands of solder have different amounts of flux in them. I had to return an entire roll of "economy" solder because it left a massive amount of flux mess all over my work. The Kester will be much cleaner and solve most of the problem.

For cleaning, I like to dip a toothbrush into a capfull of alcohol. The bristles do a good job of getting between pins. Dry with a paper towel.
 
Goof Off or acetone work better than isopropyl.
For cleaning flux, I use a mixture of Denatured Alcohol(~90%) and Naphtha(~10%). Way better than IPA and doesn't give off the horrible vapors like Goof Off. It's also very inexpensive at Home Depot/Lowes...

I use a little glass solvent pump dispenser
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~Brad
 
So, in my recent experience with working on a Taito SI cocktail (that I got a lot of help from you folks, btw)...

**Edit** thanks in particular to @Arcade2007 !

When I pulled the GM-140 monitor chassis out of the game, it was just covered in what looked like goopy flux all over. I can say for certain that I was the first person to remove the monitor chassis, every nut/bolt fastener still had the red thread locker on it, and they had never been cracked.

Either the chassis left the factory like this in 1978, or maybe somehow something got spilled onto the chassis at some point, but whatever...

Point is that the whole PCB was just shiny from some sticky build-up, which looks like 45 yr old flux to me. Look by the adjustment pots...

The only thing I could cut it with was with naptha & alcohol, like Brad mentioned. My mix for this one was probably more like 50/50 though, because this stuff was set up like amber.

I use these nylon brushes for cleaning boards. I find they work very well.


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Love it. That looks amazing.

That goop (or something like it) is on a lot of G07's, as well as G05-802 deflection boards. (Both Electrohome, FWIW.)

It's like there was a different process for soldering these, which used a different kind of flux. Not as clean as later boards. I've always wondered how it was different, as the industry seemed to get away from it at some point.
 
IKR? Every G07 I've ever worked on looks like this. I'm convinced that Electrohome's factory was actually on fire during the production of these. Dig that F901 fuse holder this one came in with...

Before and after of this G07 I just finished up. Hit it with simple green before the repair, and cleaned up after with naptha/alcohol w/ those nylon brushes.
 

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