I've calmed down a little bit (just a little).
Firstly, I have no issue whatsoever with people asking questions or having a discussion about different opinions. In fact that's how you learn and become more knowledgeable. On the other hand, I'll be damned if I'm going to let two self-professed know-it-alls who don't have 1/100 the professional board repair experience I have--and have probably never attended a professional electronics seminar, training session or conference where things like this are discussed--call me full of shit.
As I said I've just calmed down a little bit. Although I do still get a laugh every time I think about Clay's suggestion that mustard is better than vinegar in neutralizing alkaline damage and picture someone pushing the mustard under a chip with a toothpick (or maybe a cocktail wienie). I will be telling that story at the next conference I speak at.
I can confidently state that all professional board repair/rework facilities use acid to neutralize base damage on a board and use a base to neutralize acid damage on a board (as is recommended by the IPC). Of course they don't use vinegar (or mustard), they pay about 10 times as much for something with roughly the same pH. I figured since you have to buy the professional solution by the barrel, most hobbyists would prefer an equivalent solution.
For those hobbyists who are now totally confused about chemically neutralizing alkaline damage let me explain the fallacies in the previous assertions. After this I'm done with the thread and when I have time will post the information on my website where people can have respectful discussions.
For anyone interested there's already an article on media blasting on my free website.
1. You will never get glass bead media into all the nooks and crannies where alkili hide since the beads are thousands of times larger than an alkali molecule. Have a look at the inductor on a WPC CPU board (shown below) and explain to me how the media gets in-between the coils of wire and neutralizes the alkali that have seeped in there. The same is true all over the board.
2. If you do not chemically clean the board then you will need to remove all of the chips, sockets and connectors. Because if even one has some alkali under it you're screwed since clearly bead blasting will not get under components.
3. If you bead blast before you neutralize the alkali that is "above the surface" you are in fact spreading the alkali molecules around the board and contaminating other areas. At this point you need to clean the entire board, not just part of it.
4. If you look at the photos I've posted above you can see where the alkali has gotten under the solder mask. Where else do you think it's hiding that you can't see?
Now let's talk about bead blasting.
1. Most hobbyists aren't going to bead blast their boards. Therefore a combination of chemical and physical (sandpaper or whatever) is needed. In fact if Clay would have shut-up and just listened he would have found that I do a three step process: chemically neutralize the damage, bead blast the board and chemically neutralize it again.
2. According to a study done by NASA, glass beads create an electro-static discharge of -1,764 to -2,097 volts during media blasting. This was deemed to be "unacceptable levels of surface voltages." In other words you are potentially damaging components. Therefore you really should use an ESD safe micro-blaster. The reason for the micro-blaster as compared to using a sand-blasting rig, which is a serious no-no by the way, is so you can control and minimize the media hitting sensitive components (CMOS and other chips for example). You also want to prevent damage to the component packages.
3. Even the board repair guys aren't going to spend several thousand dollars for an ESD micro-blaster. Although I do have a reasonably priced (home-made) recommendation in my media blasting article above.
4. Since you should be doing controlled media blasting and not bombarding chips you are not going to remove all alkali. How are you going to get under all of the resistors, for example, without damaging the coating on the resistor. The answer is you can't unless you lightly bead blast in which case you're probably not getting all of the alkali. See the image below where I damaged a resistor package while bead blasting.
5. Any type of physical cleaning requires you to see where the damage is. As I have previously stated alkali is not always a visible white powder or displayed by dark spots under the solder mask. In other words if you're relying on the physical approach you would have to remove every bit of solder mask on the lower part of the board because any of it could be contaminated.
6. FYI Clay, glass bead are so 1980's. Most board repair/rework facilities are now using wheat starch.
Rather than tell everyone they're an idiot if they don't do it my way, I'll leave it up to each of you to make up your own minds based on the information provided.
This is how you have a discussion Clay, rather than making hyperbolic, ill-informed statements and calling people out. Of course as I said before this isn't about neutralizing alkaline damage, it's about your ego.
This thread is a perfect example of why Pinside can't have nice things.