Electronics Repair (sci.electronics.repair) Discussion of repairing electronic equipment. Topics include requests for assistance, where to obtain servicing information and parts, techniques for diagnosis and repair, and annecdotes about success, failures and problems.

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Sounds a bit like one of those late night cable programs "When Good Snakes
Go Bad" :-)

We have discussed this topic on here a number of times, and one thing that
usually comes up is how you get the stuff off. There's a switcher that I do
which has a pair of small radial electrolytics 'folded over' and glued down
on top of a whole bunch of surface mount components on the small drive /
control sub-board. Some of the components that are under the glue run quite
hot - a zener for instance - and this has a double whammy effect on the
board in that first it turns the glue brown, which then becomes conductive,
and then it also does a nice job of conducting the heat into the caps, to
ultimately **** those as well.

The glue gets right down between the pins of the PWM / driver IC amongst
other places, and is an absolute bitch to remove, without damaging assorted
gnat's-bollock sized support components in the vicinity.

Well, today, quite by accident, I discovered that my favoured flux removal
chemical - Servisol Deflux 160 aerosol - does a nice job of softening the
glue up. Not quite to the point of actually dissolving it, but enough that
it can then be fairly easily picked off with a fine scalpel blade, and then
scrubbed off with an old toothbrush, once you've got the thick of it off.

Arfa

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On Tue, 11 Sep 2012 17:42:06 +0100, "Arfa Daily"
wrote:

Well, today, quite by accident, I discovered that my favoured flux removal
chemical - Servisol Deflux 160 aerosol - does a nice job of softening the
glue up.


Nice find.
http://www.farnell.com/datasheets/1323625.pdf
Looks like it's mostly naptha (white gas, Coleman fuel, etc) and
ether. I vaguely recall finding that the yellow crud is an acrylic,
which is attacked by both naptha and ethers. MEK or acetone would
work better but would probably wreck other parts on the PCB.

http://www.alibaba.com/product-gs/482344777/One_component_solvent_resistant_flame_retardant.ht ml
http://www.aliexpress.com/store/product/accept-sample-order-wholesale-flame-retardant-yellow-adhesive-free-shipping-for-you/906248_439369255.html
http://www.sonycid.jp/en/products/mc4/sc121.html


--
Jeff Liebermann
150 Felker St #D
http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
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"Arfa Daily" wrote in message
...
Sounds a bit like one of those late night cable programs "When Good Snakes
Go Bad" :-)

We have discussed this topic on here a number of times, and one thing that
usually comes up is how you get the stuff off. There's a switcher that I
do which has a pair of small radial electrolytics 'folded over' and glued
down on top of a whole bunch of surface mount components on the small
drive / control sub-board. Some of the components that are under the glue
run quite hot - a zener for instance - and this has a double whammy effect
on the board in that first it turns the glue brown, which then becomes
conductive, and then it also does a nice job of conducting the heat into
the caps, to ultimately **** those as well.

The glue gets right down between the pins of the PWM / driver IC amongst
other places, and is an absolute bitch to remove, without damaging
assorted gnat's-bollock sized support components in the vicinity.

Well, today, quite by accident, I discovered that my favoured flux removal
chemical - Servisol Deflux 160 aerosol - does a nice job of softening the
glue up. Not quite to the point of actually dissolving it, but enough that
it can then be fairly easily picked off with a fine scalpel blade, and
then scrubbed off with an old toothbrush, once you've got the thick of it
off.

Arfa



Thanks, I've a pair of Tannoy powered monitors caked in the stuff.
As luck would have it I've just finished a can of Deflux 160.


These Tannoy still have a lot of the original yellow in it, I was wondering
WTF I was going to do about it because it does not want to shift easily at
all.
They have used it everywhere.



Cheers,

Gareth.

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Arfa Daily wrote:

Sounds a bit like one of those late night cable programs "When Good Snakes
Go Bad" :-)

We have discussed this topic on here a number of times, and one thing that
usually comes up is how you get the stuff off. There's a switcher that I do
which has a pair of small radial electrolytics 'folded over' and glued down
on top of a whole bunch of surface mount components on the small drive /
control sub-board. Some of the components that are under the glue run quite
hot - a zener for instance - and this has a double whammy effect on the
board in that first it turns the glue brown, which then becomes conductive,
and then it also does a nice job of conducting the heat into the caps, to
ultimately **** those as well.

The glue gets right down between the pins of the PWM / driver IC amongst
other places, and is an absolute bitch to remove, without damaging assorted
gnat's-bollock sized support components in the vicinity.

Well, today, quite by accident, I discovered that my favoured flux removal
chemical - Servisol Deflux 160 aerosol - does a nice job of softening the
glue up. Not quite to the point of actually dissolving it, but enough that
it can then be fairly easily picked off with a fine scalpel blade, and then
scrubbed off with an old toothbrush, once you've got the thick of it off.



Is there a MSDS for that chemical?
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p.s.

I also find Deflux 160 great for removing permanent marker etc from mixing
desks.

(the usual precautions to be applied with plastics)



Gareth.



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Gareth Magennis wrote:

p.s.

I also find Deflux 160 great for removing permanent marker etc from mixing
desks.

(the usual precautions to be applied with plastics)



I use a citrus based solvent for that. 'Goo Gone Pro Power'

http://googone.com/GG-Browse-Products/Goo-Gone-Quart

http://googone.com/c.983960/site/gg/..._Pro_Power.pdf
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"Michael A. Terrell" wrote in message
news

Arfa Daily wrote:

Sounds a bit like one of those late night cable programs "When Good
Snakes
Go Bad" :-)

We have discussed this topic on here a number of times, and one thing
that
usually comes up is how you get the stuff off. There's a switcher that I
do
which has a pair of small radial electrolytics 'folded over' and glued
down
on top of a whole bunch of surface mount components on the small drive /
control sub-board. Some of the components that are under the glue run
quite
hot - a zener for instance - and this has a double whammy effect on the
board in that first it turns the glue brown, which then becomes
conductive,
and then it also does a nice job of conducting the heat into the caps, to
ultimately **** those as well.

The glue gets right down between the pins of the PWM / driver IC amongst
other places, and is an absolute bitch to remove, without damaging
assorted
gnat's-bollock sized support components in the vicinity.

Well, today, quite by accident, I discovered that my favoured flux
removal
chemical - Servisol Deflux 160 aerosol - does a nice job of softening the
glue up. Not quite to the point of actually dissolving it, but enough
that
it can then be fairly easily picked off with a fine scalpel blade, and
then
scrubbed off with an old toothbrush, once you've got the thick of it off.



Is there a MSDS for that chemical?


Yes, several at the bottom of this page

http://uk.farnell.com/servisol/10001...0ml/dp/3821470

One little 'rider' that I should attach to this, as there seems to be more
than a little interest, is that the choice of toothbrush is quite important.
Cheapo clear coloured plastic supermarket jobs are a no-no with Deflux 160.
The bristles just fall out in very short order. I always use a 'Reach' brand
which is white plastic with rubber grips built into the handle. These are
completely untouched by the '160, and last until the bristles are worn down
to stubs. Actually, this one

http://www.boots.com/en/Reach-Interd...othbrush_1235/

Arfa

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Arfa Daily wrote:

"Michael A. Terrell" wrote in message
news

Arfa Daily wrote:

Sounds a bit like one of those late night cable programs "When Good
Snakes
Go Bad" :-)

We have discussed this topic on here a number of times, and one thing
that
usually comes up is how you get the stuff off. There's a switcher that I
do
which has a pair of small radial electrolytics 'folded over' and glued
down
on top of a whole bunch of surface mount components on the small drive /
control sub-board. Some of the components that are under the glue run
quite
hot - a zener for instance - and this has a double whammy effect on the
board in that first it turns the glue brown, which then becomes
conductive,
and then it also does a nice job of conducting the heat into the caps, to
ultimately **** those as well.

The glue gets right down between the pins of the PWM / driver IC amongst
other places, and is an absolute bitch to remove, without damaging
assorted
gnat's-bollock sized support components in the vicinity.

Well, today, quite by accident, I discovered that my favoured flux
removal
chemical - Servisol Deflux 160 aerosol - does a nice job of softening the
glue up. Not quite to the point of actually dissolving it, but enough
that
it can then be fairly easily picked off with a fine scalpel blade, and
then
scrubbed off with an old toothbrush, once you've got the thick of it off.



Is there a MSDS for that chemical?


Yes, several at the bottom of this page

http://uk.farnell.com/servisol/10001...0ml/dp/3821470

One little 'rider' that I should attach to this, as there seems to be more
than a little interest, is that the choice of toothbrush is quite important.
Cheapo clear coloured plastic supermarket jobs are a no-no with Deflux 160.
The bristles just fall out in very short order. I always use a 'Reach' brand
which is white plastic with rubber grips built into the handle. These are
completely untouched by the '160, and last until the bristles are worn down
to stubs. Actually, this one

http://www.boots.com/en/Reach-Interd...othbrush_1235/



I like the nylon brush in this set. It is like the old typewriter
brushes.

http://www.harborfreight.com/3-piece...set-40439.html
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Arfa Daily wrote:
Sounds a bit like one of those late night cable programs "When Good Snakes
Go Bad" :-)

We have discussed this topic on here a number of times, and one thing that
usually comes up is how you get the stuff off. There's a switcher that I do
which has a pair of small radial electrolytics 'folded over' and glued down
on top of a whole bunch of surface mount components on the small drive /
control sub-board. Some of the components that are under the glue run quite
hot - a zener for instance - and this has a double whammy effect on the
board in that first it turns the glue brown, which then becomes conductive,
and then it also does a nice job of conducting the heat into the caps, to
ultimately **** those as well.

The glue gets right down between the pins of the PWM / driver IC amongst
other places, and is an absolute bitch to remove, without damaging assorted
gnat's-bollock sized support components in the vicinity.

Well, today, quite by accident, I discovered that my favoured flux removal
chemical - Servisol Deflux 160 aerosol - does a nice job of softening the
glue up. Not quite to the point of actually dissolving it, but enough that
it can then be fairly easily picked off with a fine scalpel blade, and then
scrubbed off with an old toothbrush, once you've got the thick of it off.

Arfa


I hate that stuff, and anybody that ever decided to use it.

that silicone caulk they use these days is even more obnoxious. Some seem
to have huge amounts of a tough filler. All electronic junk with that
stuff should be dumped into the drinking water suppplies in the country
that produced it.


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En el artículo , Arfa Daily
escribió:

Well, today, quite by accident, I discovered that my favoured flux removal
chemical - Servisol Deflux 160 aerosol - does a nice job of softening the
glue up.


I've used IPA (isopropanol) and a half-inch paintbrush with all but an
inch of the bristles cut off for years. No scraping needed.

--
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(='.'=)
(")_(")


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"Mike Tomlinson" wrote in message
...
En el artículo , Arfa Daily
escribió:

Well, today, quite by accident, I discovered that my favoured flux removal
chemical - Servisol Deflux 160 aerosol - does a nice job of softening the
glue up.


I've used IPA (isopropanol) and a half-inch paintbrush with all but an
inch of the bristles cut off for years. No scraping needed.


I reckon you must be using either different IPA than me, or dealing with a
different yellow glue then ! Before this week's discovery that Servisol 160
has at least a 'softening' effect, and loosens its attachment to the board
and the components that it has stuck to, I've never found anything readily
to hand that as much as touches it - and I use loads of electronics grade
IPA for board and general cleaning. Have I just been unlucky ? Has anyone
else found that they can get the stuff off with IPA ? There has been a lot
of discussion over the years on this glue, and the effects of it ageing and
turning brown, and one of the recurring questions in the threads has always
been how to get the stuff off without inflicting damage on the board, hence
the reason that I thought it worth passing on this latest finding ...

Arfa


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Arfa Daily wrote in message
...


"Mike Tomlinson" wrote in message
...
En el artículo , Arfa Daily
escribió:

Well, today, quite by accident, I discovered that my favoured flux

removal
chemical - Servisol Deflux 160 aerosol - does a nice job of softening

the
glue up.


I've used IPA (isopropanol) and a half-inch paintbrush with all but an
inch of the bristles cut off for years. No scraping needed.


I reckon you must be using either different IPA than me, or dealing with a
different yellow glue then ! Before this week's discovery that Servisol

160
has at least a 'softening' effect, and loosens its attachment to the board
and the components that it has stuck to, I've never found anything readily
to hand that as much as touches it - and I use loads of electronics grade
IPA for board and general cleaning. Have I just been unlucky ? Has anyone
else found that they can get the stuff off with IPA ? There has been a lot
of discussion over the years on this glue, and the effects of it ageing

and
turning brown, and one of the recurring questions in the threads has

always
been how to get the stuff off without inflicting damage on the board,

hence
the reason that I thought it worth passing on this latest finding ...

Arfa




You've omitted the biggest problem , itself or its breakdown product going
conductive over time.


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En el artículo , Arfa Daily
escribió:

I reckon you must be using either different IPA than me, or dealing with a
different yellow glue then !


Possibly. I'll look up the RS part number when I get back into work and
post back here with it.

Just gentle scrubbing with the paintbrush and plenty of IPA, leave it a
while, go back and it (the brown/yellow goo) falls off. It doesn't
dissolve. The silicone-based stuff is another story, however...

hence
the reason that I thought it worth passing on this latest finding ...


Hell yeah, tips always welcome :-)

--
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In article , Mike Tomlinson
writes

Possibly. I'll look up the RS part number when I get back into work and
post back here with it.


This is the stuff that works

http://uk.rs-online.com/web/p/precis...luids/0180847/

The main constituent seems to be cyclohexane.

--
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"Mike Tomlinson" wrote in message
...
In article , Mike Tomlinson
writes

Possibly. I'll look up the RS part number when I get back into work and
post back here with it.


This is the stuff that works

http://uk.rs-online.com/web/p/precis...luids/0180847/

The main constituent seems to be cyclohexane.

--
(\_/)
(='.'=)
(")_(")


Noted. Cheers

Arfa



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"Mike Tomlinson" wrote in message
...
In article , Mike Tomlinson
writes

Possibly. I'll look up the RS part number when I get back into work and
post back here with it.


This is the stuff that works

http://uk.rs-online.com/web/p/precis...luids/0180847/

The main constituent seems to be cyclohexane.

--
(\_/)
(='.'=)
(")_(")


Ah. So are you saying that it's not in fact IPA that you are using ?

Arfa

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En el artículo , Arfa Daily
escribió:

Ah. So are you saying that it's not in fact IPA that you are using ?


Yes, apologies. I have both IPA and the above stuff on my bench. The
'stuff' is what works to get rid of the brown goop.

--
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(='.'=)
(")_(")
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On 9/11/2012 11:42 AM, Arfa Daily wrote:
Sounds a bit like one of those late night cable programs "When Good
Snakes Go Bad" :-)

We have discussed this topic on here a number of times, and one thing
that usually comes up is how you get the stuff off. There's a switcher
that I do which has a pair of small radial electrolytics 'folded over'
and glued down on top of a whole bunch of surface mount components on
the small drive / control sub-board. Some of the components that are
under the glue run quite hot - a zener for instance - and this has a
double whammy effect on the board in that first it turns the glue brown,
which then becomes conductive, and then it also does a nice job of
conducting the heat into the caps, to ultimately **** those as well.

The glue gets right down between the pins of the PWM / driver IC amongst
other places, and is an absolute bitch to remove, without damaging
assorted gnat's-bollock sized support components in the vicinity.

Well, today, quite by accident, I discovered that my favoured flux
removal chemical - Servisol Deflux 160 aerosol - does a nice job of
softening the glue up. Not quite to the point of actually dissolving it,
but enough that it can then be fairly easily picked off with a fine
scalpel blade, and then scrubbed off with an old toothbrush, once you've
got the thick of it off.

Arfa


Seems like word would have got around about glue on PCB's.
I remember Sony having a service letter about problems caused
by glue on 3/4" Umatic VCR machines in the 70's.
"or was that the 1/2" reel to reel video recorders" :-)
Mikek
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"Mike Tomlinson" wrote in message
...
En el artículo , Arfa Daily
escribió:

Ah. So are you saying that it's not in fact IPA that you are using ?


Yes, apologies. I have both IPA and the above stuff on my bench. The
'stuff' is what works to get rid of the brown goop.

--
(\_/)
(='.'=)
(")_(")


OK. That makes sense then, Mike. I thought I wasn't going mad ! I use a lot
of IPA, and I was certain that it didn't touch the yellow glue. Seems like
the stuff from RS that you are using, acts on it in much the same way as the
Servisol 160 - that is that it sort of softens it to 'marzipan', and breaks
its bond to whatever it's stuck to. Not perfect by any means, but better
than trying to just pick the stuff off ...

Arfa

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"amdx" wrote in message
...
On 9/11/2012 11:42 AM, Arfa Daily wrote:
Sounds a bit like one of those late night cable programs "When Good
Snakes Go Bad" :-)

We have discussed this topic on here a number of times, and one thing
that usually comes up is how you get the stuff off. There's a switcher
that I do which has a pair of small radial electrolytics 'folded over'
and glued down on top of a whole bunch of surface mount components on
the small drive / control sub-board. Some of the components that are
under the glue run quite hot - a zener for instance - and this has a
double whammy effect on the board in that first it turns the glue brown,
which then becomes conductive, and then it also does a nice job of
conducting the heat into the caps, to ultimately **** those as well.

The glue gets right down between the pins of the PWM / driver IC amongst
other places, and is an absolute bitch to remove, without damaging
assorted gnat's-bollock sized support components in the vicinity.

Well, today, quite by accident, I discovered that my favoured flux
removal chemical - Servisol Deflux 160 aerosol - does a nice job of
softening the glue up. Not quite to the point of actually dissolving it,
but enough that it can then be fairly easily picked off with a fine
scalpel blade, and then scrubbed off with an old toothbrush, once you've
got the thick of it off.

Arfa


Seems like word would have got around about glue on PCB's.
I remember Sony having a service letter about problems caused
by glue on 3/4" Umatic VCR machines in the 70's.
"or was that the 1/2" reel to reel video recorders" :-)
Mikek


Indeed. It's been discussed on here many times over the years, and the fact
that it goes brown, and breaks down into something else that is both
conductive and apparently hygroscopic, is well known amongst service
engineers. Yet still manufacturers use it in places where it is definitely
not to be recommended, such as sources of heat and high voltage, which seem
to exacerbate the problems it causes.

Arfa

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