How to clean an electronic board

benyflyguy

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52F4AD8D-FB18-4A03-A675-DE1CDDA7548D.jpeg it either someone spilt a sticky substance on this board or a battery leaked. I’m leaning toward the latter. What is the best way to clean it. The liquid doesn’t just evaporate, I was just wiping off with a paper towel carefully.
 
Horse would tell you to spray it down with some water, but that’s not good advice.
 
Horse would tell you to spray it down with some water, but that’s not good advice.

Why? I rinse all my boards off under running water after soldering them in order get rid of the solder flux. It's a pretty standard practice.

Unless you're concerned that the water will take whatever liquid spilled on the board and spread it into tight spaces?
 
Horse would tell you to spray it down with some water, but that’s not good advice.
Some lacquer thinner should clean it right up.

(Don’t do this)
 
Believe it or not it is actually industry practice (in many cases) to clean CCAs in some sort of an aqueous solution. Many times it is simply a water/alcohol based solution. I work with space grade PWBs/CCAs (which are stupidly expensive btw) and we use Ionox, which is more or less a water/alcohol solution. We have both immersion and a "glorified" dishwasher for cleaning CCAs.

That said, for a hobbyist, I would recommend starting with just some IPA. I do a lot of soldering myself on small flight control boards and have used IPA for years for general cleaning purposes. If you need something more heavy duty, MG Chemicals makes a good Flux Remover (which if you look at the SDS is essentially an alcohol based solution as well) that will really clean a board nicely.
 
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That said, for a hobbyist, I would recommend starting with just some IPA. I do a lot of soldering myself on small flight control boards and have used IPA for years for general cleaning purposes. If you need something more heavy duty, MG Chemicals makes a good Flux Remover (which if you look at the SDS is essentially an alcohol based solution as well) that will really clean a board nicely.

IPA? Which one?

Alesmith-IPA1.png

ci-goose-island-ipa-158e904177a3d9f0.jpeg
 
gentle soap, and water, scrub with soft paint brush, rinse with rubbing alcohol.
 
When I do soldering on boards, I pour an eyeball 50/50 mix of acetone and isopropyl alcohol into a shallow dish and apply it to the board with a toothbrush and wipe it up with lint-free wipes after. Cleans them up like new. Not sure if it'll work in your situation because I don't know what is on the board. But couldn't hurt.

Edit: I wrote denatured but I meant isopropyl.
 
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It’s definitely something that leaked out of a D-cell battery. Just looked at the others I have andone other leaked. Bastards!!! So going to order some of the cmc stuff I guess and spray it down and clean with a qtip the areas it seems stickier.
 
I have used a couple different methods. One is indeed rubbing alcohol. @Tom-D 's suggestion of a paint brush is also a favorite, especially trying to get between those multiple pin connectors or under components. Allow to dry thoroughly before applying power ;)

I've also used WD40 and low air pressure if the above isn't available. And it may help with future corrosion issues.
http://www.wd40.com.au/faqs/wd-40-multi-use-product-safe-electrical-parts/
Be sure to clean the WD40 off good, if you intend to solder afterwards.

side note - Soft paint brushes seem to work fairly well when cleaning computer keyboards too.
 
My father did instrument repair for a chemical company, and he regularly washed boards in a solution that was mostly water. (They were dried in a low-temp oven, as well.) Works best with "old school" electronics, I think.
 
We use 90% isopropyl alcohol for such things.

Jim
I'm wondering how well alcohol will react with The electrolyte ammonium chloride in the form of a paste.

Isn't that what the OP said was on the board?
 
Another reason I miss Radio Shack. Would electronic contact cleaner work? I still have 2 cans from RS....I treasure them.
 
What to use for cleaning depends on what will dissolve the offending substance. Try a little isopropyl alcohol, a little water, see which one works. If neither one does, I'd probably go for acetone next. Whatever you use, I generally use a soft bristle brush to apply and scrub, then a rinse with the cleanest water to which you have access, then blow-dry.
 
Nothing beat ultrasonic cleaning in 1,1,1-Trichloroethane followed by an immersive rinse in Freon TF for getting CCAs squeaky clean.
 
I'm wondering how well alcohol will react with The electrolyte ammonium chloride in the form of a paste.

Isn't that what the OP said was on the board?
The alcohol won't react with ammonium chloride; alcohols don't react with that stuff at room temperature and no catalyst.
The OP didn't say what the material was, I only saw that it came from a D-cell, which could be zinc-carbon or an alkaline cell. If a zinc-carbon cell, it could be ammonium and/or zinc chloride. If it is an alkaline cell, it will contain potassium hydroxide.
Those are all very water soluble, I'd wash the board with water followed by the isopropyl alcohol as mentioned by others.
 
Nothing beat ultrasonic cleaning in 1,1,1-Trichloroethane followed by an immersive rinse in Freon TF for getting CCAs squeaky clean.
Yeah, I'm an old geezer who remembers that stuff too. :)
 
Water and isopropyl alcohol will work, but don't use tap water if you can avoid it. Not sure about your water, but ours is high in iron and calcium. Get a jug of distilled water and use that, then finish up with the IPA. You might want to bake it at a low temp for a few hours to make sure you dry out any moisture that's become trapped.
 
Thank you all for the help. Will get distilled water and some isopropyl. There is an LCD attached with a ribbon harness that I don’t think will be ok in the oven. At this point it’s a 300 dollar bill to replace and not working at all..so I can’t make worse! Will
Keep u posted.
 
Sorry, I didn't see the "battery crud" part of the OPs post. Most all batteries these days are alkaline; I haven't seen a carbon-zinc dry cell in years. I neutralize the alkaline goop with vinegar cut 50-50 with water and quickly after that an alcohol-water 50-50 bath.

Jim
 
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