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Comment by raicem | Hacker News Reader

> These commenters are speaking authoritatively on subjects about which they are completely ignorant, but they are strident in doing so because they are repeating what everybody knows. They are intellectually secure in the center of a vast mob; their wisdom was received, not crafted.

This is an important takeaway for me, maybe even more than “electirc devices are washable”.

World is filled with conventional wisdom that limits us in countless directions. Knowing how things work empower us to break these “rules”.

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It's not the water that's the issue generally - it's the minerals in the water.

The article author got lucky this time - when electronics die from water contact, it's usually the minerals bridging connections and creating shorts. Letting the device dry does not remove those shorts. Some places have such hard water (lots of minerals) that evaporated water leaves calcium, limestone and other deposits on the surface of everything it's touched.

Does that mean doing it once will always cause an issue? Of course not... but repeatedly doing this, and/or becoming used to washing electronics in the dishwasher is a recipe to ruin them in the long term.

I would not personally want to play games with a toaster that can be replaced for $20 at your local Walmart...

dried calcium carbonate is not a very good conductor, and neither calcium carbonate nor calcium oxide is deliquescent

(edit: i said 'calcium chloride' which is of course both wrong and irrelevant)

i think the bigger issue with electronics is overheating their electrolytic capacitors

you do realize the reason why fires get started is because things become a BAD conductor right?

it's not that simple. it's because things are medium bad conductors, like the nichrome wire in the toaster, which is absolutely fantastic for setting things on fire

things that are really good conductors like the copper wires in the toaster don't heat up (much) because they don't drop much voltage, and things that are really bad conductors, like the panels that support the nichrome wires and like calcium carbonate, don't heat up at all, because they don't carry any current. it's the things that are in between that cause fires: they can carry enough current to be a problem, while also dropping enough voltage to be a problem

this has been introductory electrical engineering 101. i'll be here all week, don't forget to tip your server, and read chapters 1 of horowitz & hill by monday

that's partially true; however, I still think I was right.

yes, there are places that don't heat up because the current doesn't go through them, but only because they have easier paths. if the electricity wanted to go through them, they would heat up hotter than anything else.

the point is, things can corrode, electricity goes in places it wasn't intended or through resistances it wasn't intended, and becomes a fire hazard.

Would mineral deposits be sufficiently large and conductive that they would cause an actual issue between components?

They would probably represent nothing more than minor stray resistance/capacitance.

Assuming it was conductive enough, a scales bridge between higher voltage parts would just represent a path of material a few microns thick that would vaporize as soon as the toaster would be plugged in.

For other electronic devices, any component with a hole, like a microphone, barometric, humidity sensor, or mechanical (HDD), is more likely to suffer a more permanent fate. If water gets inside a relay housing, chemicals from the washing liquid may damage or gunk the contacts and reduce their life. LCD screens, glued parts and thin plastics don't fare well in dishwashers either...

A lot of household appliances use potted relays and conformal coatings. If you pull the control board out of your clothes washer you'll see what I mean. It's particularly important because the control board is often within spitting distance of a solenoid that's holding back 60-80 psi of water.

> Would mineral deposits be sufficiently large and conductive that they would cause an actual issue between components?

> They would probably represent nothing more than minor stray resistance/capacitance.

Spoken like someone who has never maintained any electronic devices. Skepticism should err on the side of risk management.

>Would mineral deposits be sufficiently large and conductive that they would cause an actual issue between components?

A good proportion of water-damaged cellphones can be revived just by washing the logic board thoroughly in isopropyl alcohol. It's possible that this is due to small amounts of water trapped in crevices, but I've seen it work on boards that looked bone-dry under the microscope.

Crevices could be inside components. Alcohol will extract the water by diluting it and then evaporating

totally agree, I had an electrical device catch on fire because of this exact instance

Once electronics gets wet (like stuff you plug into a wall), it usually should be discarded for safety's sake.

edit: its not just that, the water causes the copper to oxidise and swell, touching places it shouldnt

After you take it out of the dishwasher, rinse it with distilled water, then let it dry.

A $20 something you are about to throw away is the perfect thing to play games with.

It’s the fire risk that’s the issue not 20$.

What fire risk if it's in a dishwasher? :)

You only save money if you plug it in afterwards. At which point residue poses a fire risk.

Also, many dishwashers have a garbage disposal which isn’t inside the water and may fail if the cord gets into it. Not likely to happen, but enough people try it and someone may directly get an electrical fire while the dishwasher is running.

To be fair, a toaster is always a fire risk. That's why the manual says never put them under flammable things. You should always assume your toaster will catch fire.

The toaster body itself may not be a big deal, but the cord and plug are also going to be a risk here.

A toaster (at least a cheap toaster) is an electrical device, not an electronic one, as stated by the author in the article. Please look up the difference if you don't know what it is.

We have toasters that run linux, connect to the internet, and play doom. Explain to me how they aren't electronic devices.

Even cheap toasters (I take toaster apart for fun) have true electronics these days because it's usually cheaper to implement things like timers electronically and if the toaster has a display it certainly has some electronics. But I suspect that the absolute simplest toasters are purely mechanical and electrical.

Most toasters these days actually use a PT8A2514A (https://www.diodes.com/assets/Datasheets/PT8A2514A.pdf) microcontroller. But it is still safe to wash, for the same reason as it is usually safe to wash a keyboard.

It's not every day you see a datasheet with a "bagel" in the diagram.

I was curious so I did some searching -- this is the cheapest toaster that I'm aware of in the US, and it surprisingly does have a custom IC that handles the timing: https://www.youtube.com/watch?v=zLFG068HtgM

Why not play such games? If it works, it works; if it fails, it only costs $20 to replace at your local Walmart!

Because failure modes of toasters may include fire.

A toaster is normally filled with dessicated carbohydrate particles, which are an explosive fire risk.

I would think going through dishwasher would significantly reduce the fire risk.

And once you start using it again they begin replenishing.

Except now the toaster may or may not be compromised in some way. There’s no amount of benefit here worth even a minuscule risk of a house fire.

Of course I've seen the opposite all the time. People who find issues with the conventional reasoning, and then apply their own _extremely faulty reasoning_ to reach their own conclusion!

Someone having incorrect reasoning doesn't mean they are wrong, just that they do not know (in the sense of knowing something for the right reasons)

Case in point: OP decided to wash the toaster in the dishwasher. Their story about walking through water assuming that their hair dryer experiment validated them walking through water with a bunch of sockets.... they are applying super hand-wavy reasoning in the same way as the critics are!

The funny thing about the whole piece is that while "an unplugged toaster through the washing machine is probably fine" is not a huge leap, so much in the PS is indicative of how I would not really trust this person much for their decision making

> so much in the PS is indicative of how I would not really trust this person much for their decision making

That escalated fast.

If he is this reckless with toasters - imagine the dangers he poses to his students!

OTOH I find few people trustworthy in decision making of any kind.

Spot on. This “teacher” is doing a piss-poor job of challenging “conventional wisdom” that saves lives. What are students learning from him cavalierly running a hairdryer underwater and marching into electrified water?

Yes, electricians often have plenty of experience with getting shocked. But all it takes is one dumb mistake and you quickly die a horrible death, with muscles locked up unable to self-rescue in a location where immediate bystanders will risk their own lives to rescue.

What kind of dumbass proudly tells about wading into electrified flooding in front of colleagues when there wasn’t even any urgent reason to do so? What would it have cost to simply wait and cut the power first, calling the power company if necessary if a breaker box could not be safely reached for some reason (unlikely)?

And many/most circuits outside code-compliant kitchens and baths aren’t GFCI, and GFCI doesn’t protect against all electrocutions (you can be electrocuted in a short without a ground fault). Now consider electrical fires from getting sloppy with damaged wiring and electrical devices, which are a leading cause of deaths from fire.

I've always put my (dumb, wired) keyboards in the dishwasher and they have always come out great.

I'm a statistic of one, though. I don't know if I just got lucky.

Are they dumb? Isn't there a microprocessor in every keyboard?

Yes, and it is perfectly safe to wash a simple circuit board, as long as the rinse water is clean, and it gets dried reasonable quickly. Both conditions are met in a dishwasher.

Yes, sorry, I meant there's no battery.

Microprocessors (especially older ones) are _very_ hard to kill. They're a piece of silicon embedded in epoxy essentially, very inert. There are a lot of people who wash arcade PCBs in the dishwasher, not a practice I endorse, but it works.

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