Cleaning keyboards & mice & phonesa with alchol...

[Jeff Liebermann]

On Thu, 10 Mar 2022 06:49:55 -0800 (PST), Tim R
<timothy42bach@gmail.com> wrote:

I\'m not an electrical engineer but I don\'t think that\'s complete.
Other things can be current besides electrons, and in liquids
wouldn\'t the current be from other than electrons?

Nope. Just electrons (and holes). The electrons can be part of many
elements and molecules. The electrons are what \"moves\" in solutions
and wires. I don\'t know of any molecule or ion that will \"move\" in
the same manner as electrons. Electrons will move (conduct) through a
solid wire, through a conductive liquid, and through an ionized gas,
all connected in series without any chemical or physical change.
Electrons can even be convinced to flow through a vacuum. When you
talk about conductivity, you\'re really talking about the movement
(displacement) of electrons (or holes) through a solid, liquid, or
gas.

Water conducts very slightly, because a small amount of molecules
are dissociated into H+ and OH-. These would travel through the
fluid to the electrodes.

Nope. The ions do not travel through a solid wire.

Distilled water is an insulator.
<https://archive.epa.gov/water/archive/web/html/vms59.html>
<quote>
Conductivity is measured in micromhos per centimeter (µmhos/cm) or
microsiemens per centimeter (µs/cm). Distilled water has a
conductivity in the range of 0.5 to 3 µmhos/cm. The conductivity of
rivers in the United States generally ranges from 50 to 1500 µmhos/cm.
Studies of inland fresh waters indicate that streams supporting good
mixed fisheries have a range between 150 and 500 µhos/cm. Conductivity
outside this range could indicate that the water is not suitable for
certain species of fish or macroinvertebrates. Industrial waters can
range as high as 10,000 µmhos/cm.
</quote>

Take a look at TDS (total dissolved solids) meters.
<https://www.google.com/search?q=TDS+meter&tbm=isch>
These are commonly used to test for the total amount of crud in our
drinking water. Mostly, they react to the HCl (hydrochloric acid)
added to our water to kill off bacteria. There are also pH meters,
that will indicate if your favorite beverage is acidic or alkaline.

Incidentally, distilled (or de-ionized) water is tasteless. The
quality of good drinking water is not in the water, but rather in the
ionized additives.

I would imagine a small amount of isopropyl alcohol dissociates
into C3H7+ and OH- also.

Nope. Alcohols do not easily ionize. I\'ll spare you the organic
chemistry involved:
\"THE IONIZATION OF ALCOHOLS\"
<https://pubs.acs.org/doi/10.1021/ja01659a002>
In any case, like water, pure alcohol is an insulator because it
doesn\'t have any loosely bound electrons to promote conduction.

The EEs I knew talked about holes carrying current, I never really
grasped that but didn\'t need to.

Think of holes as the temporary lack of a loosely bound electron.
Holes are a term of convenience. Electric current was originally
declared to flow from + to - by Ben Franklin in about 1746. It wasn\'t
until 1897 that J.J. Thomson discovered the electron. 150 years of
doing it wrong was difficult to fix. The invention of semiconductors
and doping in about 1950, which uses both electron and hole flow
models, made things worse. So, electronics is still stuck with Ben
Franklin\'s hole flow, while physics and chemistry have successfully
switched to electron flow.


--
Jeff Liebermann jeffl@cruzio.com
PO Box 272 http://www.LearnByDestroying.com
Ben Lomond CA 95005-0272
Skype: JeffLiebermann AE6KS 831-336-2558

 

[Peter W.]

> Skype: JeffLiebermann AE6KS 831-336-2558

Jeff:

You are micturating vertically onto a braided convenience. For some the \"science\" is too much to handle in light of infinite \'what if\' speculations.

Mit der Dummheit kämpfen Götter selbst vergebens.

Schiller

Peter Wieck
Melrose Park, PA

 

[whit3rd]

On Thursday, March 10, 2022 at 6:49:59 AM UTC-8, timoth...@gmail.com wrote:

On Friday, February 25, 2022 at 10:19:26 PM UTC-5, YK wrote:

Why is rubbing alcohol not conductive?
It has electrons.

Electrons are current.
I\'m not an electrical engineer but I don\'t think that\'s complete. Other things can be current besides electrons, and in liquids wouldn\'t the current be from other than electrons?

Water conducts very slightly, because a small amount of molecules are dissociated into H+ and OH-. These would travel through the fluid to the electrodes. I would imagine a small amount of isopropyl alcohol dissociates into C3H7+ and OH- also.

Rubbing alcohol is hygroscopic (it absorbs water from normal ambient air). So, cleaning
with alcohol will usually, after the alcohol residue evaporates, leave a water film.
The water will evaporate, too (it\'s \'distilled\' from the air, so there\'s no residues expected),
but takes longer than alcohol. A printed circuit with water exposure will air-dry in
a few days at room temperature.

No isopropanol is \'pure\' after being exposed to air, like for a cleaning task. It\'s likely the water
that mainly contributes to conduction, either due to intrinsic dissociation or to pH from
minor contaminants (aka \'buffer agents\') that didn\'t get cleaned off.

 

[Phil Allison]

Witless IDIOT whit3rd wrote:

============================

Rubbing alcohol is hygroscopic (it absorbs water from normal ambient air).

** Very slowly....

> So, cleaning with alcohol will usually, after the alcohol residue evaporates, leave a water film.

** Not usually, the BPs are similar so both evap at once.

The water will evaporate, too (it\'s \'distilled\' from the air, so there\'s no residues expected),
but takes longer than alcohol. A printed circuit with water exposure will air-dry in
a few days at room temperature.

** Wrong - more likely it will take minutes, not days.
No more than 5 in a warm oven.

FYI

I regularly clean very dirty PCBs in hot water & dish washing liquid - rinse and then dry in a oven at 100C for 5 to 10 mins.
Come out looking like new.


...... Phil

 

[Jeff Liebermann]

On Thu, 10 Mar 2022 11:27:14 -0800 (PST), \"Peter W.\"
<peterwieck33@gmail.com> wrote:

>You are micturating vertically onto a braided convenience.

Hardly. I have half a kidney missing, which makes such feats of
urination difficult or impossible.

For some the \"science\" is too much to handle in light of
infinite \'what if\' speculations.

What if I explained the science in terms that the reader asking the
question might understand? While my explanations would never be
sufficient to pacify a genuine expert, I would think they would be
sufficient for someone of average intelligence wanting to know the
basics or at least what words to use for a subsequent Google search.

For example, think of an air gap transformer. Electrons go into the
primary winding. Electrons also leave the secondary winding. However,
in between, there are no electrons, only air. It also works in a
vacuum, so it\'s not electron movement via conduction through air
molecules. So, what happened?

Mit der Dummheit kämpfen Götter selbst vergebens.
Schiller

<https://en.wikipedia.org/wiki/The_Maid_of_Orleans_(play)>
\"Against stupidity, the gods themselves battle in vain.\"

Whom are you calling stupid? The person who asked an interesting
question, or me who dared to answer it?

Peter Wieck
Melrose Park, PA

--
Jeff Liebermann jeffl@cruzio.com
PO Box 272 http://www.LearnByDestroying.com
Ben Lomond CA 95005-0272
Skype: JeffLiebermann AE6KS 831-336-2558

 

[Mike Coon]

In article <po8k2h9c46rmks39tmaqo3aimn2b8ekg4j@4ax.com>,
jeffl@cruzio.com says...

On Thu, 10 Mar 2022 06:49:55 -0800 (PST), Tim R
timothy42bach@gmail.com> wrote:

I\'m not an electrical engineer but I don\'t think that\'s complete.
Other things can be current besides electrons, and in liquids
wouldn\'t the current be from other than electrons?

Nope. Just electrons (and holes). The electrons can be part of many
elements and molecules. The electrons are what \"moves\" in solutions
and wires. I don\'t know of any molecule or ion that will \"move\" in
the same manner as electrons. Electrons will move (conduct) through a
solid wire, through a conductive liquid, and through an ionized gas,
all connected in series without any chemical or physical change.
Electrons can even be convinced to flow through a vacuum. When you
talk about conductivity, you\'re really talking about the movement
(displacement) of electrons (or holes) through a solid, liquid, or
gas.

Water conducts very slightly, because a small amount of molecules
are dissociated into H+ and OH-. These would travel through the
fluid to the electrodes.

Nope. The ions do not travel through a solid wire.

Distilled water is an insulator.
https://archive.epa.gov/water/archive/web/html/vms59.html
quote
Conductivity is measured in micromhos per centimeter (µmhos/cm) or
microsiemens per centimeter (µs/cm). Distilled water has a
conductivity in the range of 0.5 to 3 µmhos/cm. The conductivity of
rivers in the United States generally ranges from 50 to 1500 µmhos/cm.
Studies of inland fresh waters indicate that streams supporting good
mixed fisheries have a range between 150 and 500 µhos/cm. Conductivity
outside this range could indicate that the water is not suitable for
certain species of fish or macroinvertebrates. Industrial waters can
range as high as 10,000 µmhos/cm.
/quote

Take a look at TDS (total dissolved solids) meters.
https://www.google.com/search?q=TDS+meter&tbm=isch
These are commonly used to test for the total amount of crud in our
drinking water. Mostly, they react to the HCl (hydrochloric acid)
added to our water to kill off bacteria. There are also pH meters,
that will indicate if your favorite beverage is acidic or alkaline.

Incidentally, distilled (or de-ionized) water is tasteless. The
quality of good drinking water is not in the water, but rather in the
ionized additives.

Electroplating works precisely because the ions move to the electrode
through the electrolyte and stick to it.

 

[Peter W.]

Whom are you calling stupid? The person who asked an interesting
question, or me who dared to answer it?

Jeff:

No such thing as a stupid question - but for the one not asked. But, the individual you are attempting to \'educate\' is not asking questions, but speculating. There may be a question-mark after the speculation, but it is not a question.

\"The time has come\", the Walrus said, \"To talk of many things: Of shoes - and ships - and sealing wax - Of cabbages - and kings- And why the sea is boiling hot - And whether pigs have wings.\"

It is nonsense. And attempting to enforce \'science\' or \'discipline\' or \'rigor\' on nonsense is an exercise in futility. As you are ever-the-gentleman, you are much more prone to grant others the benefit of the doubt - I am far less tolerant than you are. Not that I do not enjoy nonsense. It has its place and it can be great good fun.

Peter Wieck
Melrose Park, PA

 

[Tim R]

On Friday, March 11, 2022 at 5:16:06 AM UTC-5, Mike Coon wrote:

Electroplating works precisely because the ions move to the electrode
through the electrolyte and stick to it.

Corrosion is the same.
Ions move through the electrolyte, when they hit the dissimilar metal (which can be the same surface just at a place with slightly different electronegativity) then electrons move through the metal, so you have a complete circuit. I\'ve not done any electroplating but had some experience with corrosion protection.

So in a case like electroplating or corrosion, electrons are moving through the wired part of the circuit, ions are moving through the electrolyte part. The electrons that move with the ions are fixed to them, not loose like in a metal. I don\'t want to argue with Jeff but i always called that current, with ions as the charge carriers.

 

[whit3rd]

On Thursday, March 10, 2022 at 3:06:30 PM UTC-8, palli...@gmail.com wrote:

[vituperation extirpated] whit3rd wrote:

Rubbing alcohol is hygroscopic (it absorbs water from normal ambient air).
** Very slowly....
So, cleaning with alcohol will usually, after the alcohol residue evaporates, leave a water film.
** Not usually, the BPs are similar so both evap at once.
The water will evaporate, too (it\'s \'distilled\' from the air, so there\'s no residues expected),
but takes longer than alcohol. A printed circuit with water exposure will air-dry in
a few days at room temperature.
** Wrong - more likely it will take minutes, not days.

Depends on the purpose of the circuit; if nanoamps matter, or kilovolts are involved,
or components have nooks and crannies (remember, this was about keyboards to begin with)
the answer is different. How well sealed are your trimpots?

 

[ohg...@gmail.com]

On Tuesday, March 15, 2022 at 12:16:09 PM UTC-4, whit3rd wrote:

On Thursday, March 10, 2022 at 3:06:30 PM UTC-8, palli...@gmail.com wrote:
[vituperation extirpated] whit3rd wrote:

Rubbing alcohol is hygroscopic (it absorbs water from normal ambient air).
** Very slowly....
So, cleaning with alcohol will usually, after the alcohol residue evaporates, leave a water film.
** Not usually, the BPs are similar so both evap at once.
The water will evaporate, too (it\'s \'distilled\' from the air, so there\'s no residues expected),
but takes longer than alcohol. A printed circuit with water exposure will air-dry in
a few days at room temperature.
** Wrong - more likely it will take minutes, not days.
Depends on the purpose of the circuit; if nanoamps matter, or kilovolts are involved,
or components have nooks and crannies (remember, this was about keyboards to begin with)
the answer is different. How well sealed are your trimpots?

Back in the 70s, I was washing TV module and chassis boards before rebuilding them by putting them in the sink and using a commercially available sudsy ammonia cleaner cut 5:1 with water and a stiff paint brush. Before I did, I removed the transformers and anything else that would trap moisture. After washing and rinsing, I put the boards in a hotbox (cardboard box with a hole cut to fit the snout of a hair dryer) on low heat for about an hour, then reassembled. So clean they even shined. Never had a problem, but as you say, you\'ve got to make sure there\'s no trapped moisture.

 

[Phil Allison]

Witless Wanker Fuckwit wrote:
========================

Rubbing alcohol is hygroscopic (it absorbs water from normal ambient air).
** Very slowly....
So, cleaning with alcohol will usually, after the alcohol residue evaporates, leave a water film.
** Not usually, the BPs are similar so both evap at once.
The water will evaporate, too (it\'s \'distilled\' from the air, so there\'s no residues expected),
but takes longer than alcohol. A printed circuit with water exposure will air-dry in
a few days at room temperature.

** Wrong - more likely it will take minutes, not days.

Depends on the purpose of the circuit; if nanoamps matter, or kilovolts are involved,

** Context shift ?

> or components have nooks and crannies (remember, this was about keyboards to begin with)

** Quote: \" A printed circuit ... \"

Congenital LIARS slyly shift contexts and deliberately misquote.

Was it your mom or your dad who taught you to lie and cheat ?

Fuck you.


....... Phil

 

[whit3rd]

On Tuesday, March 15, 2022 at 2:01:57 PM UTC-7, palli...@gmail.com wrote:

whit3rd wrote:

...A printed circuit with water exposure will air-dry in
a few days at room temperature.

** Wrong - more likely it will take minutes, not days.

Depends on the purpose of the circuit; if nanoamps matter, or kilovolts are involved,
** Context shift ?
or components have nooks and crannies (remember, this was about keyboards to begin with)

** Quote: \" A printed circuit ... \"

Yeah, so? Do you see a lot of keyboards that are hand-wired, without a printed
circuit (sometimes flexible) attaching the other components? I\'ve cleaned a few by
total-immersion dipping.

 

[Peter W.]

Yeah, so? Do you see a lot of keyboards that are hand-wired, without a printed
circuit (sometimes flexible) attaching the other components? I\'ve cleaned a few by
total-immersion dipping.

Mpfff, yep! Or top rack in the dishwasher (Bosch), batteries out (wireless types), delicate cycle, 1/4 detergent load.

Not lost a patient yet. About once per year. Clean as the proverbial whistle.

Peter Wieck
Melrose Park, PA