Water, I guess.

I remember an old thread about how to wash boards. Some people use water and detergent. I wash my boards with that and they are fine. It takes a lot of time to dry them but it's cheap and they look brand new.

Not even detergent. Just plain-ol water 😀

use simple green or one of its bazillion 'clones'.

I've heard many people doing this (even washing keyboards in the dishwasher), but I'm still reluctant to douse my electronic components in water.
Granted, you have to make sure it completely dries out. Maybe I will try it one day on a motherboard and/or keyboard I don't mind losing.

Just be sure to remove chipset heatsinks (if you can) and use forced dry air to dry it. It takes some time but works wonderful. Also remove bios battery.
I use detergent when serious dirt is involved. Some people manages to spill thermal.compound everywhere. And when a capacitor starts leaking it's best to be sure that the board is clean enough. Otherwise I just use water and works well too.

If you use a dishwasher, then remember to remove and electronic device you wash that has plastic on it, before the dry cycle kicks in full. Keyboards should be fine, as I've never had an issue with them. I did have an arcade PCB the had a couple plastic standoffs I couldn't remove without breaking them, go through the dry cycle and melt all over the board and rack. Also, sun dry the clean device for 48 hours after shake and drain and a quick once over with the hai dryer.

Kodai wrote:

If you use a dishwasher, then remember to remove and electronic device you wash that has plastic on it, before the dry cycle kicks in full. Keyboards should be fine, as I've never had an issue with them. I did have an arcade PCB the had a couple plastic standoffs I couldn't remove without breaking them, go through the dry cycle and melt all over the board and rack. Also, sun dry the clean device for 48 hours after shake and drain and a quick once over with the hai dryer.

These should be OK on the top rack.

This was over 20 years ago, but I did use the top rack. I think it was a Golly Ghost PCB (been so long, I cant remember anymore), but it had a set of plastic spacers that were placed on the PCB and heat sealed together. Thats why I couldn't remove them without breaking them. I do remember placing it on the top rack, and when I went to take the PCB out, the rather large corner spacers had melted all over the PCB and rack. Most electronics that have plastic made of nylon, and that should be able to handle the heat cycle on the top rack, but these were made of some sort of cheap, brittle, plastic that melted everywhere. Its a rare thing to worry about, but once it happens you cant help but take a few extra precautions.

As far as the OP's original dilemma, I'm at a loss. I've never run into a conformal coating that cant handle IPA. Run into many that IPA doesn't do a damn thing in so far as cleaning goes, but not one that is removed from it. My guess is its based off lacquer, and for the most part, they stopped using that on PCB's back in the 70's. If it is a lacquer based coating, then nothing is really going to clean it well without removing it. Anything with any type of alcohol in it will melt lacquer away like a hot knife through butter.

Here is a thought. Give the board a bath in 91% or better IPA (if you can find it get a gallon of pure or 100% denatured alcohol at a local Lowes, Home Depot, or whatever big box DIY store you have access too), and strip the board of its conformal coating. Then do a full cleaning and inspection touching up any joints that look like they could use a reheat. Then get some clear, hard coat shellac and brush it over the board with a fine haired brush. It dries quick and two or three coats could be done within an hour. The board will look brand new and it should restore its original protection as it sounds like its only some sort of shellac to begin with.

I guess I am one of those people who does not believe in using water when it comes to electronics. I may try to use distilled water one day though.

Kodai wrote:

As far as the OP's original dilemma, I'm at a loss.

You can see it by using rubbing alcohol on a Pentium III CPU.

And here this whole time I've been using rubbing alcohol to clean my electronics. Shit. 😵

mr_bigmouth_502 wrote:

And here this whole time I've been using rubbing alcohol to clean my electronics. Shit. 😵

You probably shouldn't worry too much, so far I've only noticed this effect on Pentium III CPUs. Their green PCBs just lose that shine finish after use of rubbing alcohol. It doesn't affect their working condition either.

Dreamer_of_the_past wrote:

mr_bigmouth_502 wrote:

And here this whole time I've been using rubbing alcohol to clean my electronics. Shit. 😵

You probably shouldn't worry too much, so far I've only noticed this effect on Pentium III CPUs. Their green PCBs just lose that shine finish after use of rubbing alcohol. It doesn't affect their working condition either.

It's been a while since I've done anything with Pentium IIIs, but I think I've noticed this effect before as well. I guess it's something to keep in mind if you collect CPUs.

Dreamer_of_the_past wrote:

I guess I am one of those people who does not believe in using water when it comes to electronics.

At the factory where they make those electronics, they use water to wash them before packing and shipping.

Sorry for yet another rez 😊

I've used rubbing alcohol extensively, but afaicr I've never (or perhaps a single time) used rubbing alcohol directly on PCBs, mostly because I don't think it's even needed.

I always try to use as few 'chemicals' as possible and usually only resort to rubbing alcohol when I'm trying to remove thermal goo or when cleaning the top off of CPUs. I do however vaguely remember having seen something like this when cleaning sA CPUs, as those for whatever reason were often drowning in that nasty thermal stuff that's very hard to remove (the silvery stuff), but I kinda thought it was that stuff or the rubbing itself that did that, though I also considered it being some kind of residue. I never really dove into the matter as I was never presented with malfunctions because of this.

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