"Do not use solvents on electronic equipment"

[Sammy]

Many instruction booklets for domestic electronic equipment say do
not use cleaning solvents such as alcohol.

Is this advice given simply because they are trying to prevent
possible marking of the plastic casing?

Or can domestic cleaning solvents actually damage the electronics
inside in some way?

 

"Sammy" <no-one@no-where.com> wrote in message
news:Xns9789850A75F8A451E7A@66.250.146.159...

Many instruction booklets for domestic electronic equipment say do
not use cleaning solvents such as alcohol.

Is this advice given simply because they are trying to prevent
possible marking of the plastic casing?

Or can domestic cleaning solvents actually damage the electronics
inside in some way?

It is my impression that they dodge the entire gamut of liability this way.

If you used alcohol under their good graces, and disfigured the appliance,
or started it up and it caught fire, they would be liable.

It is your appliance...do what you wish, realizing that if you screw up,
it is on your own account.

 

[Ben Miller]

"Sammy" <no-one@no-where.com> wrote in message
news:Xns9789850A75F8A451E7A@66.250.146.159...

Many instruction booklets for domestic electronic equipment say do
not use cleaning solvents such as alcohol.

Is this advice given simply because they are trying to prevent
possible marking of the plastic casing?

Or can domestic cleaning solvents actually damage the electronics
inside in some way?

Alcohol and many other solvents degrade some plastics. This can not only
ruin the external appearance, but could affect insulation properties if the
material develops cracks.

Ben Miller

--
Benjamin D. Miller, PE
B. MILLER ENGINEERING
www.bmillerengineering.com

 

[Spehro Pefhany]

On Fri, 17 Mar 2006 14:12:24 GMT, the renowned <HLS@nospam.nix> wrote:

"Sammy" <no-one@no-where.com> wrote in message
news:Xns9789850A75F8A451E7A@66.250.146.159...
Many instruction booklets for domestic electronic equipment say do
not use cleaning solvents such as alcohol.

Is this advice given simply because they are trying to prevent
possible marking of the plastic casing?

Or can domestic cleaning solvents actually damage the electronics
inside in some way?

It is my impression that they dodge the entire gamut of liability this way.

If you used alcohol under their good graces, and disfigured the appliance,
or started it up and it caught fire, they would be liable.

It is your appliance...do what you wish, realizing that if you screw up,
it is on your own account.

In any case, alcohol is a pretty mild solvent to most electronic
components and housings. Things like petroleum solvents are more
likely to cause damage (eg. lacquer thinner) and acetone (eg. some
nail polish removers) is rather likely to cause damage to plastics or
to remove markings.

For the outside, a damp (NOT sopping wet) cloth, perhaps with a bit of
detergent is the safest, but I've never seen alcohol damage anything.


Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
speff@interlog.com Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com

 

[Long Ranger]

"Sammy" <no-one@no-where.com> wrote in message
news:Xns9789850A75F8A451E7A@66.250.146.159...

Many instruction booklets for domestic electronic equipment say do
not use cleaning solvents such as alcohol.

Is this advice given simply because they are trying to prevent
possible marking of the plastic casing?

Or can domestic cleaning solvents actually damage the electronics
inside in some way?

In my experience chlorinated solvents can instantly ruin certain plastics.
You don't find much of that anymore since the tree huggers came up with
their horse-shit about chlorine harming the ozone layer. I have washed down
some circuit boards with "plastic safe" spray solvents, only to see the
potting overlay dissolve into goo. One thing to remember about alcohol is
that the stuff you buy in the market called "Rubbing Alcohol" is mixed with
both water, and glycerin. The water is fairly innocuous, but the glycerin
leaves a faint oily residue on things. Not exactly the best pre-cleaner for
adhesives etc. Better to get friendly with your pharmacist and get some pure
isopropyl alcohol from him. I think pure isopropyl is a regulated thing
because it can be used in drug manufacture or something tlike that. Anyway,
it raises an eyebrow when you ask for it.One thing you can try as a last
resort on a non-functioning board before you trash it: Run it through your
dishwasher in the top rack with about half the usual dish powder. Obviously
this won't work when things like mechanical pots etc are incorporated, but I
have restored otherwise non-functioning boards several times like that.
There is a product called "Goof-Off" that is a really great solvent for
removing the adhesive left behind by labels, and it will even dissolve dried
latex paint fairly rapidly. You need to be very careful with it, and test
the substrate gently before you use it on plastics etc.

 

[Roy L. Fuchs]

On Fri, 17 Mar 2006 13:04:42 GMT, Sammy <no-one@no-where.com> Gave us:

Many instruction booklets for domestic electronic equipment say do
not use cleaning solvents such as alcohol.

Is this advice given simply because they are trying to prevent
possible marking of the plastic casing?

Or can domestic cleaning solvents actually damage the electronics
inside in some way?

Alcohol isn't a solvent as it relates to the components on a Circuit
Card Assembly (CCA), per se (it will solve fluxes). They are talking
about reactive solvents like lacquer thinner, or benzene, or toluene,
or other petroleum based solvents. Any of those in the family that
would melt plastic parts. Another thing a solvent can and does do is
get into the vents of an EL cap and screw them up. One has to watch
for that as well.

If you have a bare CCA in your hands (mind proper ESD procedures)
you can heat up some alcohol (90% or better) in a microwave and wash
the board down, Or immerse it, then blow it off with air and you
should see no residuals. You should also bake it out at 60C for a
bit.

Most modern assembly facilities these days use "water soluble"
fluxes, and if you have a good oven that has good temp control, you
can wash a CCA with water (not if it has transformers on it) and then
bake it out for an hour at 60C to dry the CCA and the PCB itself out.

The alcohol is what I use as it "dries" a lot easier, and requires
much less baking time (15-30min). The reason I use it hot is so it
doesn't attract water so much. Hot air gun even works if you are
careful with it.

I wouldn't use any cleaners on an assemble product that has plastic
housings, or places that can trap liquids.

I disassemble if I want PCB assembly level cleaning.

 

[Roy L. Fuchs]

On Fri, 17 Mar 2006 10:51:15 -0500, Spehro Pefhany
<speffSNIP@interlogDOTyou.knowwhat> Gave us:

On Fri, 17 Mar 2006 14:12:24 GMT, the renowned <HLS@nospam.nix> wrote:


"Sammy" <no-one@no-where.com> wrote in message
news:Xns9789850A75F8A451E7A@66.250.146.159...
Many instruction booklets for domestic electronic equipment say do
not use cleaning solvents such as alcohol.

Is this advice given simply because they are trying to prevent
possible marking of the plastic casing?

Or can domestic cleaning solvents actually damage the electronics
inside in some way?

It is my impression that they dodge the entire gamut of liability this way.

If you used alcohol under their good graces, and disfigured the appliance,
or started it up and it caught fire, they would be liable.

It is your appliance...do what you wish, realizing that if you screw up,
it is on your own account.

In any case, alcohol is a pretty mild solvent to most electronic
components and housings. Things like petroleum solvents are more
likely to cause damage (eg. lacquer thinner) and acetone (eg. some
nail polish removers) is rather likely to cause damage to plastics or
to remove markings.

For the outside, a damp (NOT sopping wet) cloth, perhaps with a bit of
detergent is the safest, but I've never seen alcohol damage anything.

Most of the plastic used for cases on products will slowly "dry out"

and degrade from the surface in, and as BM stated, can hinder the
insulative performance of the case, even though it not all that
likely. They can also discolor.

He asked about the electronics though. I spoke about cleaning the
boards if in hand, but spoke against cleaning assembled products as
there are too many places that can trap the cleaning liquid(s) used.

In any instance, care is needed to ensure that there is no liquids
left behind when the task is completed.

 

[Roy L. Fuchs]

On Fri, 17 Mar 2006 17:07:37 GMT, "Long Ranger"
<worpylorpkins@mindspring.com> Gave us:

"Sammy" <no-one@no-where.com> wrote in message
news:Xns9789850A75F8A451E7A@66.250.146.159...
Many instruction booklets for domestic electronic equipment say do
not use cleaning solvents such as alcohol.

Is this advice given simply because they are trying to prevent
possible marking of the plastic casing?

Or can domestic cleaning solvents actually damage the electronics
inside in some way?

In my experience chlorinated solvents can instantly ruin certain plastics.

Nearly ALL plastics.

You don't find much of that anymore since the tree huggers came up with
their horse-shit about chlorine harming the ozone layer.

You're a goddamned retard. The ozone hole above Antarctica ALSO has
with it a HUGE chlorine cloud, dumbass. BTW, that is a nearly TWO
decades old FACT, proven by NASA and the Space Shuttle missions.

I have washed down
some circuit boards with "plastic safe" spray solvents, only to see the
potting overlay dissolve into goo.

One should never attempt to clean a potted assembly with solvents.
MAYBE alcohol, and a subsequent oven bake cycle.

If you are talking about a conformal coating, the above still applies.

One thing to remember about alcohol is
that the stuff you buy in the market called "Rubbing Alcohol" is mixed with
both water, and glycerin.

Just water, generally.

The water is fairly innocuous, but the glycerin
leaves a faint oily residue on things. Not exactly the best pre-cleaner for
adhesives etc.

When was this thread ever about cleaning adhesives?

Better to get friendly with your pharmacist and get some pure
isopropyl alcohol from him.

Or order it from digi-key or mouser or E-bay.

I think pure isopropyl is a regulated thing
because it can be used in drug manufacture or something tlike that.

Not! Still guessing, eh loner boy?

Anyway,
it raises an eyebrow when you ask for it.

You're so full of shit, your eyes are brown, and there is a foul
stench emanating from your ears.

One thing you can try as a last
resort on a non-functioning board before you trash it: Run it through your
dishwasher in the top rack with about half the usual dish powder.

Wrong! A few drops of LIQUID soap (saponifier), but NO powders as
they can be trapped without ever "melting" into the wash.

Obviously
this won't work when things like mechanical pots etc are incorporated, but I
have restored otherwise non-functioning boards several times like that.

Hahahaha. In the restoration business, eh? What if there are
transformers on the board? Why no mention of a bake cycle to dry the
board out? Are you new to electronics, ranger boy?

There is a product called "Goof-Off" that is a really great solvent for
removing the adhesive left behind by labels,

He never said a damned thing about a label.

and it will even dissolve dried
latex paint fairly rapidly. You need to be very careful with it, and test
the substrate gently before you use it on plastics etc.

Substrate? Do you mean "test an area not visible on the finished
assembly"?

 

[y_p_w]

Roy L. Fuchs wrote:

On Fri, 17 Mar 2006 13:04:42 GMT, Sammy <no-one@no-where.com> Gave us:

Many instruction booklets for domestic electronic equipment say do
not use cleaning solvents such as alcohol.

Is this advice given simply because they are trying to prevent
possible marking of the plastic casing?

Or can domestic cleaning solvents actually damage the electronics
inside in some way?

Alcohol isn't a solvent as it relates to the components on a Circuit
Card Assembly (CCA), per se (it will solve fluxes). They are talking
about reactive solvents like lacquer thinner, or benzene, or toluene,
or other petroleum based solvents. Any of those in the family that
would melt plastic parts. Another thing a solvent can and does do is
get into the vents of an EL cap and screw them up. One has to watch
for that as well.

I believe that typical glass/epoxy circuit boards and most electronics
components are generally resistant to most solvents. It's the
housing around the electronics that's a bigger issue.

I've found a whole lot of things can damage the ABS housing used
for lots of electronic components. I have a halogenated hydrocarbon
tape head cleaner (perc). I've spilled sunscreen that's damaged the
case of a Walkman - likely some silicone emulsifier. DEET insect
repellent will eat through a host of plastics (esp clothing) including
styrenes, polyester, and spandex, as well as rayon.

 

[Spehro Pefhany]

On 17 Mar 2006 10:36:16 -0800, the renowned "y_p_w"
<y_p_w@hotmail.com> wrote:

Roy L. Fuchs wrote:
On Fri, 17 Mar 2006 13:04:42 GMT, Sammy <no-one@no-where.com> Gave us:

Many instruction booklets for domestic electronic equipment say do
not use cleaning solvents such as alcohol.

Is this advice given simply because they are trying to prevent
possible marking of the plastic casing?

Or can domestic cleaning solvents actually damage the electronics
inside in some way?

Alcohol isn't a solvent as it relates to the components on a Circuit
Card Assembly (CCA), per se (it will solve fluxes). They are talking
about reactive solvents like lacquer thinner, or benzene, or toluene,
or other petroleum based solvents. Any of those in the family that
would melt plastic parts. Another thing a solvent can and does do is
get into the vents of an EL cap and screw them up. One has to watch
for that as well.

I believe that typical glass/epoxy circuit boards and most electronics
components are generally resistant to most solvents. It's the
housing around the electronics that's a bigger issue.

I've found a whole lot of things can damage the ABS housing used
for lots of electronic components. I have a halogenated hydrocarbon
tape head cleaner (perc). I've spilled sunscreen that's damaged the
case of a Walkman - likely some silicone emulsifier. DEET insect
repellent will eat through a host of plastics (esp clothing) including
styrenes, polyester, and spandex, as well as rayon.

Acrylic can be damaged by some of the more active solvents- cause
brittleness and stress corrosion cracking (eg. where fasteners contact
the material). ABS can be softened by a lot of solvents but it does
not seem to suffer that kind of 'hidden' damage.


Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
speff@interlog.com Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com

 

[y_p_w]

Spehro Pefhany wrote:

On 17 Mar 2006 10:36:16 -0800, the renowned "y_p_w"
y_p_w@hotmail.com> wrote:
I've found a whole lot of things can damage the ABS housing used
for lots of electronic components. I have a halogenated hydrocarbon
tape head cleaner (perc). I've spilled sunscreen that's damaged the
case of a Walkman - likely some silicone emulsifier. DEET insect
repellent will eat through a host of plastics (esp clothing) including
styrenes, polyester, and spandex, as well as rayon.

Acrylic can be damaged by some of the more active solvents- cause
brittleness and stress corrosion cracking (eg. where fasteners contact
the material). ABS can be softened by a lot of solvents but it does
not seem to suffer that kind of 'hidden' damage.

I used to wear a certain brand of sunscreen that tended to feel
great on the skin. My keyboard at work has these black areas
that scrape off easily. It feels soft and sticky. Compact Disc
jewel cases are another common item that will be affected by a
host of solvents.

 

[Spehro Pefhany]

On 17 Mar 2006 13:42:09 -0800, the renowned "y_p_w"
<y_p_w@hotmail.com> wrote:

Spehro Pefhany wrote:
On 17 Mar 2006 10:36:16 -0800, the renowned "y_p_w"
y_p_w@hotmail.com> wrote:
I've found a whole lot of things can damage the ABS housing used
for lots of electronic components. I have a halogenated hydrocarbon
tape head cleaner (perc). I've spilled sunscreen that's damaged the
case of a Walkman - likely some silicone emulsifier. DEET insect
repellent will eat through a host of plastics (esp clothing) including
styrenes, polyester, and spandex, as well as rayon.

Acrylic can be damaged by some of the more active solvents- cause
brittleness and stress corrosion cracking (eg. where fasteners contact
the material). ABS can be softened by a lot of solvents but it does
not seem to suffer that kind of 'hidden' damage.

I used to wear a certain brand of sunscreen that tended to feel
great on the skin. My keyboard at work has these black areas
that scrape off easily. It feels soft and sticky. Compact Disc
jewel cases are another common item that will be affected by a
host of solvents.

CD-ROM jewel cases are typically acrylic for the clear part, and ABS
for the opaque part. I think CD jewel cases might tend towards the
cheaper polystrene for the clear part.


Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
speff@interlog.com Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com

 

[Tim Shoppa]

Sammy wrote:

Many instruction booklets for domestic electronic equipment say do
not use cleaning solvents such as alcohol.

Is this advice given simply because they are trying to prevent
possible marking of the plastic casing?

Or can domestic cleaning solvents actually damage the electronics
inside in some way?

Some cleaners can leave behind a slightly conductive residue that can
affect very-high-impedance circuits in a bad way. Most drugstore
isopropyl actually has a small amount of oil in too, and this oil can
leave behind a thin film.

In general non-oil-containing isopropyl isn't so bad for most modern
electronics.

But a note about more powerful solvents (acetones, other hydrocarbons):

Last summer I got a pair of prescription sunglass lenses put into a
pair of Ray-Ban frames. They looked fine when I took them out of the
store. But within a few hours, there were literally hundred of little
hairline cracks on the surface. I head back to Lenscrafters, and by the
time I get there the frame now is cracked into 5 or so pieces. I take
a number, explain what's happening, and we watch as the frames are
self-destructing in front of our eyes, literally falling apart into a
bunch of little grey discolored chunks. They get me an explanation: the
lab had used acetone to clean the frames after mounting the lenses, and
acetone attacks this particular lightweight plastic in an awful way.
Needless to say, I never clean this pair of glasses with anything but
water anymore!

I had thought that generally modern plastics were more resistant to
common solvents than older plastics. But the disintegration in front of
my eyes changed my mind!

Tim.

 

[y_p_w]

Spehro Pefhany wrote:

On 17 Mar 2006 13:42:09 -0800, the renowned "y_p_w"
y_p_w@hotmail.com> wrote:

Spehro Pefhany wrote:
On 17 Mar 2006 10:36:16 -0800, the renowned "y_p_w"
y_p_w@hotmail.com> wrote:
I've found a whole lot of things can damage the ABS housing used
for lots of electronic components. I have a halogenated hydrocarbon
tape head cleaner (perc). I've spilled sunscreen that's damaged the
case of a Walkman - likely some silicone emulsifier. DEET insect
repellent will eat through a host of plastics (esp clothing) including
styrenes, polyester, and spandex, as well as rayon.

Acrylic can be damaged by some of the more active solvents- cause
brittleness and stress corrosion cracking (eg. where fasteners contact
the material). ABS can be softened by a lot of solvents but it does
not seem to suffer that kind of 'hidden' damage.

I used to wear a certain brand of sunscreen that tended to feel
great on the skin. My keyboard at work has these black areas
that scrape off easily. It feels soft and sticky. Compact Disc
jewel cases are another common item that will be affected by a
host of solvents.

CD-ROM jewel cases are typically acrylic for the clear part, and ABS
for the opaque part. I think CD jewel cases might tend towards the
cheaper polystrene for the clear part.

There are several manufacturers of polypropylene CD/DVD cases.
My personal favorite is DiscSavers. They don't crack and aren't
affected by most solvents.

I'm baffled as to why polystyrene when it's well known that just
looking at it funny causes damage.

 

[Roy L. Fuchs]

On Fri, 17 Mar 2006 17:56:15 -0500, Spehro Pefhany
<speffSNIP@interlogDOTyou.knowwhat> Gave us:

On 17 Mar 2006 13:42:09 -0800, the renowned "y_p_w"
y_p_w@hotmail.com> wrote:

Spehro Pefhany wrote:
On 17 Mar 2006 10:36:16 -0800, the renowned "y_p_w"
y_p_w@hotmail.com> wrote:
I've found a whole lot of things can damage the ABS housing used
for lots of electronic components. I have a halogenated hydrocarbon
tape head cleaner (perc). I've spilled sunscreen that's damaged the
case of a Walkman - likely some silicone emulsifier. DEET insect
repellent will eat through a host of plastics (esp clothing) including
styrenes, polyester, and spandex, as well as rayon.

Acrylic can be damaged by some of the more active solvents- cause
brittleness and stress corrosion cracking (eg. where fasteners contact
the material). ABS can be softened by a lot of solvents but it does
not seem to suffer that kind of 'hidden' damage.

I used to wear a certain brand of sunscreen that tended to feel
great on the skin. My keyboard at work has these black areas
that scrape off easily. It feels soft and sticky. Compact Disc
jewel cases are another common item that will be affected by a
host of solvents.

CD-ROM jewel cases are typically acrylic for the clear part,

Polycarbonate, actually.

and ABS
for the opaque part.

Whatever. got a link?

I think CD jewel cases might tend towards the
cheaper polystrene for the clear part.

Polycarbonate throughout.

 

[Roy L. Fuchs]

On 17 Mar 2006 15:22:44 -0800, "Tim Shoppa" <shoppa@trailing-edge.com>
Gave us:

Sammy wrote:
Many instruction booklets for domestic electronic equipment say do
not use cleaning solvents such as alcohol.

Is this advice given simply because they are trying to prevent
possible marking of the plastic casing?

Or can domestic cleaning solvents actually damage the electronics
inside in some way?

Some cleaners can leave behind a slightly conductive residue that can
affect very-high-impedance circuits in a bad way. Most drugstore
isopropyl actually has a small amount of oil in too, and this oil can
leave behind a thin film.

In general non-oil-containing isopropyl isn't so bad for most modern
electronics.

But a note about more powerful solvents (acetones, other hydrocarbons):

Last summer I got a pair of prescription sunglass lenses put into a
pair of Ray-Ban frames. They looked fine when I took them out of the
store. But within a few hours, there were literally hundred of little
hairline cracks on the surface. I head back to Lenscrafters, and by the
time I get there the frame now is cracked into 5 or so pieces. I take
a number, explain what's happening, and we watch as the frames are
self-destructing in front of our eyes, literally falling apart into a
bunch of little grey discolored chunks. They get me an explanation: the
lab had used acetone to clean the frames after mounting the lenses, and
acetone attacks this particular lightweight plastic in an awful way.
Needless to say, I never clean this pair of glasses with anything but
water anymore!

I had thought that generally modern plastics were more resistant to
common solvents than older plastics. But the disintegration in front of
my eyes changed my mind!

The word for today is VULCANIZATION

http://m-w.com/dictionary/vulcanization

With rubber, it is a good thing. With plastics, it is usually a bad
thing.Especially if they weren't meant to be that way.

 

[Spehro Pefhany]

On 17 Mar 2006 15:23:01 -0800, the renowned "y_p_w"
<y_p_w@hotmail.com> wrote:

Spehro Pefhany wrote:
On 17 Mar 2006 13:42:09 -0800, the renowned "y_p_w"
y_p_w@hotmail.com> wrote:

Spehro Pefhany wrote:
On 17 Mar 2006 10:36:16 -0800, the renowned "y_p_w"
y_p_w@hotmail.com> wrote:
I've found a whole lot of things can damage the ABS housing used
for lots of electronic components. I have a halogenated hydrocarbon
tape head cleaner (perc). I've spilled sunscreen that's damaged the
case of a Walkman - likely some silicone emulsifier. DEET insect
repellent will eat through a host of plastics (esp clothing) including
styrenes, polyester, and spandex, as well as rayon.

Acrylic can be damaged by some of the more active solvents- cause
brittleness and stress corrosion cracking (eg. where fasteners contact
the material). ABS can be softened by a lot of solvents but it does
not seem to suffer that kind of 'hidden' damage.

I used to wear a certain brand of sunscreen that tended to feel
great on the skin. My keyboard at work has these black areas
that scrape off easily. It feels soft and sticky. Compact Disc
jewel cases are another common item that will be affected by a
host of solvents.

CD-ROM jewel cases are typically acrylic for the clear part, and ABS
for the opaque part. I think CD jewel cases might tend towards the
cheaper polystrene for the clear part.

There are several manufacturers of polypropylene CD/DVD cases.
My personal favorite is DiscSavers. They don't crack and aren't
affected by most solvents.

I'm baffled as to why polystyrene when it's well known that just
looking at it funny causes damage.

1) It's really clear, so it helps sell the product

2) It's really cheap

Polycarbonate would be nice, but perhaps a bit expensive (and it
scratches more easily than acrylic, and it's a bit yellow).


Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
speff@interlog.com Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com

 

[William P.N. Smith]

Sammy <no-one@no-where.com> wrote:

Many instruction booklets for domestic electronic equipment say do
not use cleaning solvents such as alcohol.

I've had rubbing alcohol ruin the translucent red cover for an LED
display on a couple of pieces of test equipment. Also, don't let the
cleaning folks with their typical spray cleaners or furniture polishes
anywere near stuff you want to see thru (VCR displays, etc).

 

[Spehro Pefhany]

On Fri, 17 Mar 2006 23:40:02 GMT, the renowned Roy L. Fuchs
<roylfuchs@urfargingicehole.org> wrote:

On Fri, 17 Mar 2006 17:56:15 -0500, Spehro Pefhany
speffSNIP@interlogDOTyou.knowwhat> Gave us:

On 17 Mar 2006 13:42:09 -0800, the renowned "y_p_w"
y_p_w@hotmail.com> wrote:

Spehro Pefhany wrote:
On 17 Mar 2006 10:36:16 -0800, the renowned "y_p_w"
y_p_w@hotmail.com> wrote:
I've found a whole lot of things can damage the ABS housing used
for lots of electronic components. I have a halogenated hydrocarbon
tape head cleaner (perc). I've spilled sunscreen that's damaged the
case of a Walkman - likely some silicone emulsifier. DEET insect
repellent will eat through a host of plastics (esp clothing) including
styrenes, polyester, and spandex, as well as rayon.

Acrylic can be damaged by some of the more active solvents- cause
brittleness and stress corrosion cracking (eg. where fasteners contact
the material). ABS can be softened by a lot of solvents but it does
not seem to suffer that kind of 'hidden' damage.

I used to wear a certain brand of sunscreen that tended to feel
great on the skin. My keyboard at work has these black areas
that scrape off easily. It feels soft and sticky. Compact Disc
jewel cases are another common item that will be affected by a
host of solvents.

CD-ROM jewel cases are typically acrylic for the clear part,

Polycarbonate, actually.

I'd like a pointer to a source of polycarbonate cases.


Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
speff@interlog.com Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com

 

[Abstract Dissonance]

"Tim Shoppa" <shoppa@trailing-edge.com> wrote in message
news:1142637764.747736.82390@z34g2000cwc.googlegroups.com...

Sammy wrote:
Many instruction booklets for domestic electronic equipment say do
not use cleaning solvents such as alcohol.

Is this advice given simply because they are trying to prevent
possible marking of the plastic casing?

Or can domestic cleaning solvents actually damage the electronics
inside in some way?

Some cleaners can leave behind a slightly conductive residue that can
affect very-high-impedance circuits in a bad way. Most drugstore
isopropyl actually has a small amount of oil in too, and this oil can
leave behind a thin film.

In general non-oil-containing isopropyl isn't so bad for most modern
electronics.

But a note about more powerful solvents (acetones, other hydrocarbons):

Last summer I got a pair of prescription sunglass lenses put into a
pair of Ray-Ban frames. They looked fine when I took them out of the
store. But within a few hours, there were literally hundred of little
hairline cracks on the surface. I head back to Lenscrafters, and by the
time I get there the frame now is cracked into 5 or so pieces. I take
a number, explain what's happening, and we watch as the frames are
self-destructing in front of our eyes, literally falling apart into a
bunch of little grey discolored chunks. They get me an explanation: the
lab had used acetone to clean the frames after mounting the lenses, and
acetone attacks this particular lightweight plastic in an awful way.
Needless to say, I never clean this pair of glasses with anything but
water anymore!

I had thought that generally modern plastics were more resistant to
common solvents than older plastics. But the disintegration in front of
my eyes changed my mind!

Tim.

I wonder if this is there method to get you to buy from them again?