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Re:Silica Gel Took over the World by Workaccount2 on Tuesday April 01, 2025 @08:08PM (#43552545)
You are better off soaking the wet electronics in isopropyl alcohol then trying to dry them in a bag full of desiccant.

One of the things that kills wet electronics is the dried residue that is left behind, creating shorts. Alcohol will wash away the water and leave no residue after it dries.

If the device has ink or glue you'd like to try to preserve, deionized water will mostly work too.

Re:Silica Gel Took over the World by lightedman on Tuesday April 01, 2025 @08:40PM (#43552700)
At my work any electronics that have had a water bath or flux-added rework will get an ultrasonic alcohol bath and then a forced air drying run. Alcohol is just so damned good for so much.
Re:Silica Gel Took over the World by dieselgate on Tuesday April 01, 2025 @10:52PM (#43553265)
What percentage alcohol is used?
Re:Silica Gel Took over the World by arcmechanica on Wednesday April 02, 2025 @01:59AM (#43554013)
usually 99%
Re:Silica Gel Took over the World by lightedman on Wednesday April 02, 2025 @11:27PM (#43564368)
99%. 70% if I'm doing parts disinfection for medical devices.
Re:Silica Gel Took over the World by wkat4242 on Tuesday April 01, 2025 @08:46PM (#43552736)
I totally agree though my use of it is pretty different ;)
Re:Silica Gel Took over the World by fellerts on Wednesday April 02, 2025 @04:19AM (#43554637)
I'd be very scared of IPA in an ultrasonic cleaner. Sounds like a recipe for a fire. Or is your machine perhaps designed for safe IPA cleaning?
Re:Silica Gel Took over the World by jdietrich on Wednesday April 02, 2025 @05:56AM (#43555126)
A few companies do make ultrasonic cleaners that are designed for flammable solvents, but they aren't common.

The easiest option is to just fill a plastic food bag with solvent, throw your part in, seal it with a clip and float it in your ultrasonic bath. The bag contains the vapour for safety, and it's easy to switch between different solvents and solutions.

Re:Silica Gel Took over the World by 0_____0 on Wednesday April 02, 2025 @10:10AM (#43556893)
That's a quite elegant solution I hadn't considered before.
Re:Silica Gel Took over the World by adolph on Wednesday April 02, 2025 @11:10AM (#43557559)
That is next generation sous vide. Just controlling temperature is ho-hum. Getting it to just the right ultrasonic vibration to "cross-modulate the adipose frequency" is next level.

And someone is already doing it:

https://besservacuum.com/en/ultrasonic-food-treatment-machin...

Re:Silica Gel Took over the World by hilbert42 on Wednesday April 02, 2025 @06:01AM (#43555163)
I've used both EtOH and propan-2-ol (IPA) for decades in ultrasonic cleaners both at room temperature and heated (quite warm to feel but not boiling hot) and never had a problem with fire.
Re:Silica Gel Took over the World by benjijay on Wednesday April 02, 2025 @05:00AM (#43554859)
I'm scrolling before coffee and initially took your acronym as India Pale Ale, which would certainly be a different cleaning experience...
Re:Silica Gel Took over the World by Retr0id on Wednesday April 02, 2025 @04:34AM (#43554705)
Do ultrasonic cleaners get hot?
Re:Silica Gel Took over the World by adlpz on Wednesday April 02, 2025 @05:58AM (#43555143)
I've run isopropyl alcohol in an ultrasonic cleaner.

It did get significantly hot after a while. And smelly, so it was surely aerosoling (is that a word?) somewhat.

I did it outdoors and away from anything that could catch fire because it felt rightly sketchy.

Re:Silica Gel Took over the World by numpad0 on Wednesday April 02, 2025 @06:41AM (#43555368)
It's basically an industrial ultrasonic humidifier attached to the bottom of a buffet tray. And it does get warm.
Re:Silica Gel Took over the World by actionfromafar on Wednesday April 02, 2025 @04:37AM (#43554723)
Typically not (though some have heaters you can apply) but they atomize the fluid pretty well. The tiniest spark (static electricity) and some bad luck and you have the lid shooting into the roof and then a fire. As with everything, if you know what you are doing, go ahead.
Re:Silica Gel Took over the World by bradyd on Wednesday April 02, 2025 @01:07PM (#43558871)
A lot of ultrasonic cleaners have a heating element.
Re:Silica Gel Took over the World by lightedman on Wednesday April 02, 2025 @11:26PM (#43564358)
The machine doesn't get hotter than 50C. IPA isnt igniting at that temp.
Re:Silica Gel Took over the World by nullc on Thursday April 03, 2025 @03:06AM (#43565879)
Even more spicy is vapor phase cleaning... evaporate the solvent, condense on the part to be cleaned suspended above it. Very effective since the impurities are constantly distilled out.

Also kinda explody.

Re:Silica Gel Took over the World by nyanpasu64 on Tuesday April 01, 2025 @09:36PM (#43552949)
One time I tried drying a water-soaked smartphone in alcohol, but the alcohol got under the LCD screen and made it look blotchy permanently. The phone still worked but I stopped using it.
Re:Silica Gel Took over the World by nicoburns on Wednesday April 02, 2025 @06:14AM (#43555226)
I think the protocol would generally be to disassemble the device and then clean with alcohol. Easier said than done with a phone of course.
Re:Silica Gel Took over the World by owenversteeg on Wednesday April 02, 2025 @02:55PM (#43560154)
Yeah, I've had the same issue; as far as I can tell it's not actually the LCD itself but the backlight and the diffuser that end up getting screwed up. If you're trying to save electronics, keep the isopropanol away from the screen.
Re:Silica Gel Took over the World by epakai on Friday April 04, 2025 @09:32AM (#43582117)
I did this with a surface go. I managed to drive off the alcohol with a heating plate. It took a few attempts. I think I heated it to 80 C or maybe even 100 C on the last run. End result was clean, except for a small line, possibly cracked diffuser.

I ruined a Thinkpad display the same way in the past, so I went for broke.

Re:Silica Gel Took over the World by hilbert42 on Wednesday April 02, 2025 @05:18AM (#43554940)
"You are better off soaking the wet electronics in isopropyl alcohol."

Where I am ethanol (EtOH-95%, H2O-5%) is much cheaper and much more readily available and works almost as well. If silica gel is not available, then a fan works well followed by a warm (not hot) oven baking. Make sure the alcohol has essentially all evaporated first.

Keep in mind that some components can be affected by both EtOH and propan-2-ol — component markings, coil doping resins can dissolve, etc. Both alcohols are also good at removing solder flux resins/residues. (Oh for the days when freon and freon mixtures were available, component damage never happened.)

Devices with power transformers pose special problems, best to dry with alcohol first (hoping enamel coatings on wire aren't softened), then bake in oven on warm heat for a long while, sometimes 24 hours or more is necessary. With transformers it's important that this is done as soon as possible after wetting.

Edit: as I'm reminded by nyanpasu64 keep both alcohols away from LCD screens (likely all screens). I had a netbook PC and put it in a carry bag with a bottle of EtOH and it leaked. The PC still worked but the screen suffered the same outcome.

Re:Silica Gel Took over the World by SirHumphrey on Wednesday April 02, 2025 @05:37AM (#43555022)
That may be country specific, but at least where I live, ethanol is much more expensive than isopropyl alcohol (30€/l vs 10€/l) - mostly because of dues on ethanol.
Re:Silica Gel Took over the World by hilbert42 on Wednesday April 02, 2025 @05:51AM (#43555103)
Right, if you live where duty is applied to ethanol then it's expensive. In Australia, where I am ethanol is available as a denatured product. That is, it includes a very small amount (much less than 1%) of denatonium (aka Bitrex) which renders it undrinkable (it's the bitterest substance known). As such, excise tax is not levied.

Here, one liter bottles of denatured ethanol are available in every supermarket everywhere, and up to 20 liters available in hardware stores (at bulk rates it's even cheaper).

For comparison, here denatured ethanol costs about $5/l [in US dollars] versus isopropyl at between $25 and $30/l.

Re:Silica Gel Took over the World by DebtDeflation on Wednesday April 02, 2025 @06:31AM (#43555319)
In the United States, if you buy "Denatured Alcohol" at a big box store, it will be a toxic brew of often 50-60% methanol as well as smaller amounts of MEK, MIBK, and even acetone in addition to the ethanol. However, you can order "Specially Denatured Alcohol (SDA)" from various chemical suppliers or even Amazon. "SDA 40B 200" will be 99.5% ethanol with 0.1% tert-butyl alcohol and 0.0005% denatonium benzoate. It's what I use for camp stove fuel since I refuse to carry methanol in my pack with food.
Re:Silica Gel Took over the World by hilbert42 on Wednesday April 02, 2025 @06:46AM (#43555389)
I understand the problem with purchasing EtOH in the US. Frankly, I consider adding MeOH, MEK, etc. to denature it as both dangerous and an archaic procedure. (Moreover, outside lab reagents, MeOH should never exist without denatonium, it's just too dangerous.)

Some people will drink EtOH whether it's denatured with MeOH, etc. or with the much safer denatonium. Why blind or kill these people when one doesn't need to? Sure, EtOH will likely get them anyway but why should the State be their executioner?

There's something awfully wrong with that I reckon.

Re:Silica Gel Took over the World by InDubioProRubio on Wednesday April 02, 2025 @08:49AM (#43556068)
Puritan wrath, a nice mixture of hatred of ones own ant-existance and hatred on others not participating the labour camp race to the bottom, thats why?
Re:Silica Gel Took over the World by 0_____0 on Wednesday April 02, 2025 @10:08AM (#43556869)
Typically I would dismiss this as a bit overwrought but I came back from overseas last week and promptly was forced to drive in Boston, an activity that both takes place in the heart of US puritanism and perfectly encapsulates something that is frustrating in a way that could only happen in a place where "it's shit, it's supposed to be shit, and if you don't like it, there's the door" is a core principle.
Re:Silica Gel Took over the World by hilbert42 on Wednesday April 02, 2025 @11:27AM (#43557771)
Right, I was being polite, my question was rhetorical.
Re:Silica Gel Took over the World by 1oooqooq on Wednesday April 02, 2025 @09:19AM (#43556375)
it's cheaper and the free market is regulating itself as god intended.
Re:Silica Gel Took over the World by AStonesThrow on Friday April 04, 2025 @02:11AM (#43578853)
I had a recent adventure attempting to replenish my Food Grade 35% Hydrogen Peroxide.

Amazon wouldn't even ship the stuff here. I'm coming to realize that any truly potent or powerful substance is strictly off-limits in consumer spaces. Plenty of good reasons for that. But such things as pure isopropyl and pure H2O2 are so versatile and tantalizing to have on-hand, rather than household cleaners with proprietary formulas, as much dilution as possible, unique MSDS, and obnoxious fake fragrance.

I can walk down an entire aisle in the hardware store, chockablock with bottles of household cleaners, and they all amount to 2 or 3 active ingredients, endlessly remixed for credulous homemakers.

Re:Silica Gel Took over the World by hilbert42 on Saturday April 05, 2025 @02:17AM (#43591281)
35% — that's wishful thinking where I am. I can get 3% in a supermarket and 6% in a pharmacy. I can get H2O2 stronger than 6% but it's a major undertaking, and one is treated with suspicion and or put onto registers—like 'what the fuck do you want that dangerous stuff for?'.

"I'm coming to realize that any truly potent or powerful substance is strictly off-limits in consumer spaces."

There's no doubt about this and it's a damn pain. Outside industrial settings, chemicals that really work are becoming very difficult to get. I accept that highly concentrated (say >50%) H2O2 is dangerous and not something I want or need, and fuel grade (>70%) needs special handling thus the need for controls, but concentrations of about 20% are useful for bleaching where sodium hypochlorite is unsuitable, etc. For example, 6% H2O2 often isn't strong enough to remove foxing from documents, books, etc. so having ready access to a more concentrated solution that I could dilute to suit would be very useful.

It wasn't always like this, I'm old enough to remember when I could get most chemicals I wanted with little effort. Unfortunately, both occupational health and safety and terrorism have put the kibosh on ready availability, controls and restrictions have screwed all of us legitimate users.

Of course, restrictions covering to whom chemicals are sold haven't detrimentally affected the chemical companies one iota, in fact I'd maintain they've benefited them. They've proteced companies from potential lawsuits when users misuse chemicals and they've provided endless possibilities for them to market nigh-on-useless products to naïve consumers like the household cleaners to which you have referred. I could give examples of how some common household products have become less potent over the years but it'd take a full blog to go into details.

There's another downside here too, the less consumers know about the chemicals they use the more unskilled they become at actual chemistry—even if taught chemistry, using products whose ingredients are unknown doesn't add to their understanding. That's also a matter that I've not time to elaborate about here except to say lack of knowledge about chemicals is one of the significant reasons why society is becoming overly chemical-phobic.

Re:Silica Gel Took over the World by gpderetta on Wednesday April 02, 2025 @06:50AM (#43555398)
Isn't the ethanol denatured? There's a duty on that as well?
Re:Silica Gel Took over the World by hilbert42 on Wednesday April 02, 2025 @07:03AM (#43555468)
It is, with denatonium hence no excise tax.
Re:Silica Gel Took over the World by noname120 on Wednesday April 02, 2025 @07:57AM (#43555740)
Why not demineralized water instead of alcohol?
Re:Silica Gel Took over the World by Numerlor on Wednesday April 02, 2025 @08:37AM (#43555951)
Alcohol would dry up faster, demineralised water will have more time to dissolve and redeposit particles. Though you have to be careful with alcohol as it can destroy some plastics