Today's Lead Free Crap Solder Stories ...

[Arfa Daily]

The first is the Warrior amp that I posted on here about, looking for
schematics. None were found, and as expected, the importer ignored my pleas,
so I decided I would spend a half hour on it 'blind'.

It turned out to not be too difficult to get the main PCB out, complete with
heatsinks and back panel. The wiring was long enough to allow the board to
be turned over, without having to disconnect everything. The fault was that
one of the two identical output stages was behaving as a pretty good half
wave rectifier, but only with a load connected. With no load, an applied
sine wave was perfectly symmetrical at the output terminals, and of similar
size to the good channel. With a load connected, the negative excursions
disappeared almost totally. Nothing was burning, and the the output protect
didn't even fire until the wick was turned well up, which led me to believe
that the problem may well be back in the driver stages or earlier. As there
are two identical amps, I figured that I would start with a few comparitive
resistance checks between channels. Quickly, I found that at the base pin of
one of the driver transistors, I had a reading of 3k or so on the good
channel, but open circuit at the same point on the bad channel. I followed
the print back and took another reading and Lo! - 3k ...

So I went back to the transistor leg - open, but at the joint, 3k. I tell
you, I examined that joint with the strongest light and magnifier that I
have, but you could not see a problem with it. However, as soon as it was
resoldered, 3k on the leg as well, and the amp then worked normally. This is
the problem with lead free. You can no longer spot bad joints by eye, and
they don't behave like conventional bad joints any more.

The second one was a Vox combo. This one was reported as "goes off after a
while - tap top to get it back". It actually ran for about 2 hours, during
which time I thrashed the output stage so hard you couldn't touch the
heatsink, and periodically knocked seven bells out of it with the butt end
of a large philips screwdy. At no time did it show any signs of
intermittency. I was actually on the phone to the store that it came to me
from, to check if they knew the owner, and whether he was savvy, or a
numpty, when it went off. Just like that. No provocation. You could then
lightly tap the top of the chassis just about anywhere, and it would come
and go at will. So easy was it to make it do it, you would have thought that
the joint causing it would have been really easily spotted. I twisted and
wiggled everything I could, but nothing made it do it, but still the
lightest tap, and there it went.

Eventually, after a frustrating session of blanket resoldering that did no
good at all, I came to a power resistor standing up off the board. It was a
component that I had previously twisted. This time I pulled it, and one leg
just came right out of the board. The joint looked perfectly normal - for
lead-free that is - but it had not whetted the resistor leg at all. How the
hell could that take two hours to go bad, not be responsive at all before
that time, and then when it has gone bad, not respond to twisting, but be so
tap sensitive that you could make it come and go with a feather? I HATE
lead-free with a passion.

If it ever finds its way into avionics, be afraid, be VERY afraid ...

Arfa

 

[Wild_Bill]

For technicians in the consumer goods/home entertainment repair industry,
the present situation can be defined as BOHICA.

Manufacturers haven't been soldering consumer goods properly for decades,
and I agree with your summary, that with lead-free, it's going to get much
worse.
I'm sure some are thinking: Opportunity. No, not when the owner can buy a
new one for less than a repair job.

Did anyone own a RCA Thomson(?) TV of the 90s that didn't fail within two
years? The CTC77 type, for a few series with bad tuner shield soldering,
where the shield was used for needed circuit continuity.

Even so, much earlier, many types of electronic gear failures were a result
of soldering faults/failures.

There was a SER post years ago titled something like; why can't
manufacturers solder?

Apparently the company accountants were in charge of the speed control of
the track feed as the boards passed thru the solder wave bath, it seems.
At double speed, they could potentially save tens-of-thousands of dollars in
solder purchasing costs per year.. or something similar.

As any techs with some years of experience have seen countless times, larger
components that can dissipate more heat during the soldering phase of
manufacturing rarely get soldered properly.

Automation in board fabrication was a huge advancement in electronic
manufacturing, but that wasn't satisfactory for the
accountant/profits-driven manufacturing model.

The Chinese have taken nearly every manufacturing process to a whole 'nother
lower level, even before lead-free.
It's disgusting that the American and other countries' consumers keep buying
this shiney new worthless crap, with much of it being put out for trash
pickup within a year.. year after year (and paying to have it hauled away).
Undoubtedly, many career positions available in waste management.

Get used to the likelyhood that any vacant land will become landfill pits..
who knows, maybe even our national parks.
When the groundwater aquafers are nearly totally fuctup, a fleet of space
shuttles can start hauling it away.
Where's the koolaid line form? I wanna be at the front of the line (if I
even last much longer).

All of this low grade crap manufactured today should be imported only with a
Return to Sender Free agreement. Let them dispose of all this worthless
crap.. and I'm fairly sure they would, and sell it again as recycled, but
fresh, new products.

I try to buy older stuff that was manufactured to a slightly higher level of
quality, which may at least be repairable. Anymore, I only repair my own
stuff, or a limited number of items that I want to, for a few close friends.

What's taken place, I think, which I suspect was intentionally forced upon
most of us, is that manufacturers wanted to lower everyone's expectations of
quality.
With that accomplished, all they need to do is make sure there are shelves
full of new crap to replace the old crap with.

How many times has someone been heard saying; I'll never buy that brand
again, next time I'll buy a (different brand)?
Catch 22.. it's nearly all the same, in retail stores, anyway. Before they
know it, they choose another product from the same brand name they started
with.. and round 'n round it goes.

--
Cheers,
WB
..............


"Arfa Daily" <arfa.daily@ntlworld.com> wrote in message
news:mdlJn.18479$ea4.8777@newsfe29.ams2...

The first is the Warrior amp that I posted on here about, looking for
schematics. None were found, and as expected, the importer ignored my
pleas, so I decided I would spend a half hour on it 'blind'.

It turned out to not be too difficult to get the main PCB out, complete
with heatsinks and back panel. The wiring was long enough to allow the
board to be turned over, without having to disconnect everything. The
fault was that one of the two identical output stages was behaving as a
pretty good half wave rectifier, but only with a load connected. With no
load, an applied sine wave was perfectly symmetrical at the output
terminals, and of similar size to the good channel. With a load connected,
the negative excursions disappeared almost totally. Nothing was burning,
and the the output protect didn't even fire until the wick was turned well
up, which led me to believe that the problem may well be back in the
driver stages or earlier. As there are two identical amps, I figured that
I would start with a few comparitive resistance checks between channels.
Quickly, I found that at the base pin of one of the driver transistors, I
had a reading of 3k or so on the good channel, but open circuit at the
same point on the bad channel. I followed the print back and took another
reading and Lo! - 3k ...

So I went back to the transistor leg - open, but at the joint, 3k. I tell
you, I examined that joint with the strongest light and magnifier that I
have, but you could not see a problem with it. However, as soon as it was
resoldered, 3k on the leg as well, and the amp then worked normally. This
is the problem with lead free. You can no longer spot bad joints by eye,
and they don't behave like conventional bad joints any more.

The second one was a Vox combo. This one was reported as "goes off after a
while - tap top to get it back". It actually ran for about 2 hours, during
which time I thrashed the output stage so hard you couldn't touch the
heatsink, and periodically knocked seven bells out of it with the butt end
of a large philips screwdy. At no time did it show any signs of
intermittency. I was actually on the phone to the store that it came to me
from, to check if they knew the owner, and whether he was savvy, or a
numpty, when it went off. Just like that. No provocation. You could then
lightly tap the top of the chassis just about anywhere, and it would come
and go at will. So easy was it to make it do it, you would have thought
that the joint causing it would have been really easily spotted. I twisted
and wiggled everything I could, but nothing made it do it, but still the
lightest tap, and there it went.

Eventually, after a frustrating session of blanket resoldering that did no
good at all, I came to a power resistor standing up off the board. It was
a component that I had previously twisted. This time I pulled it, and one
leg just came right out of the board. The joint looked perfectly normal -
for lead-free that is - but it had not whetted the resistor leg at all.
How the hell could that take two hours to go bad, not be responsive at all
before that time, and then when it has gone bad, not respond to twisting,
but be so tap sensitive that you could make it come and go with a feather?
I HATE lead-free with a passion.

If it ever finds its way into avionics, be afraid, be VERY afraid ...

Arfa

 

[N_Cook]

Arfa Daily <arfa.daily@ntlworld.com> wrote in message
news:mdlJn.18479$ea4.8777@newsfe29.ams2...

The first is the Warrior amp that I posted on here about, looking for
schematics. None were found, and as expected, the importer ignored my
pleas,
so I decided I would spend a half hour on it 'blind'.

It turned out to not be too difficult to get the main PCB out, complete
with
heatsinks and back panel. The wiring was long enough to allow the board to
be turned over, without having to disconnect everything. The fault was
that
one of the two identical output stages was behaving as a pretty good half
wave rectifier, but only with a load connected. With no load, an applied
sine wave was perfectly symmetrical at the output terminals, and of
similar
size to the good channel. With a load connected, the negative excursions
disappeared almost totally. Nothing was burning, and the the output
protect
didn't even fire until the wick was turned well up, which led me to
believe
that the problem may well be back in the driver stages or earlier. As
there
are two identical amps, I figured that I would start with a few
comparitive
resistance checks between channels. Quickly, I found that at the base pin
of
one of the driver transistors, I had a reading of 3k or so on the good
channel, but open circuit at the same point on the bad channel. I followed
the print back and took another reading and Lo! - 3k ...

So I went back to the transistor leg - open, but at the joint, 3k. I tell
you, I examined that joint with the strongest light and magnifier that I
have, but you could not see a problem with it. However, as soon as it was
resoldered, 3k on the leg as well, and the amp then worked normally. This
is
the problem with lead free. You can no longer spot bad joints by eye, and
they don't behave like conventional bad joints any more.

The second one was a Vox combo. This one was reported as "goes off after a
while - tap top to get it back". It actually ran for about 2 hours, during
which time I thrashed the output stage so hard you couldn't touch the
heatsink, and periodically knocked seven bells out of it with the butt end
of a large philips screwdy. At no time did it show any signs of
intermittency. I was actually on the phone to the store that it came to me
from, to check if they knew the owner, and whether he was savvy, or a
numpty, when it went off. Just like that. No provocation. You could then
lightly tap the top of the chassis just about anywhere, and it would come
and go at will. So easy was it to make it do it, you would have thought
that
the joint causing it would have been really easily spotted. I twisted and
wiggled everything I could, but nothing made it do it, but still the
lightest tap, and there it went.

Eventually, after a frustrating session of blanket resoldering that did
no
good at all, I came to a power resistor standing up off the board. It was
a
component that I had previously twisted. This time I pulled it, and one
leg
just came right out of the board. The joint looked perfectly normal - for
lead-free that is - but it had not whetted the resistor leg at all. How
the
hell could that take two hours to go bad, not be responsive at all before
that time, and then when it has gone bad, not respond to twisting, but be
so
tap sensitive that you could make it come and go with a feather? I HATE
lead-free with a passion.

If it ever finds its way into avionics, be afraid, be VERY afraid ...

Arfa

I'm thinking of making a tug-test tool for PbF checking. Probably based on
an automatic centre punch tool latch mechanism but somehow inverted in
operation. How many ounces or grams of pullout tension do you think a 1/3 W
resistor lead/wire link/TO92 wire should resist pulling out , leaded solder
that is.


--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://diverse.4mg.com/index.htm

 

[Arfa Daily]

"N_Cook" <diverse@tcp.co.uk> wrote in message
news:ht5c0o$2m0$1@news.eternal-september.org...

Arfa Daily <arfa.daily@ntlworld.com> wrote in message
news:mdlJn.18479$ea4.8777@newsfe29.ams2...
The first is the Warrior amp that I posted on here about, looking for
schematics. None were found, and as expected, the importer ignored my
pleas,
so I decided I would spend a half hour on it 'blind'.

It turned out to not be too difficult to get the main PCB out, complete
with
heatsinks and back panel. The wiring was long enough to allow the board
to
be turned over, without having to disconnect everything. The fault was
that
one of the two identical output stages was behaving as a pretty good half
wave rectifier, but only with a load connected. With no load, an applied
sine wave was perfectly symmetrical at the output terminals, and of
similar
size to the good channel. With a load connected, the negative excursions
disappeared almost totally. Nothing was burning, and the the output
protect
didn't even fire until the wick was turned well up, which led me to
believe
that the problem may well be back in the driver stages or earlier. As
there
are two identical amps, I figured that I would start with a few
comparitive
resistance checks between channels. Quickly, I found that at the base pin
of
one of the driver transistors, I had a reading of 3k or so on the good
channel, but open circuit at the same point on the bad channel. I
followed
the print back and took another reading and Lo! - 3k ...

So I went back to the transistor leg - open, but at the joint, 3k. I tell
you, I examined that joint with the strongest light and magnifier that I
have, but you could not see a problem with it. However, as soon as it was
resoldered, 3k on the leg as well, and the amp then worked normally. This
is
the problem with lead free. You can no longer spot bad joints by eye, and
they don't behave like conventional bad joints any more.

The second one was a Vox combo. This one was reported as "goes off after
a
while - tap top to get it back". It actually ran for about 2 hours,
during
which time I thrashed the output stage so hard you couldn't touch the
heatsink, and periodically knocked seven bells out of it with the butt
end
of a large philips screwdy. At no time did it show any signs of
intermittency. I was actually on the phone to the store that it came to
me
from, to check if they knew the owner, and whether he was savvy, or a
numpty, when it went off. Just like that. No provocation. You could then
lightly tap the top of the chassis just about anywhere, and it would come
and go at will. So easy was it to make it do it, you would have thought
that
the joint causing it would have been really easily spotted. I twisted and
wiggled everything I could, but nothing made it do it, but still the
lightest tap, and there it went.

Eventually, after a frustrating session of blanket resoldering that did
no
good at all, I came to a power resistor standing up off the board. It was
a
component that I had previously twisted. This time I pulled it, and one
leg
just came right out of the board. The joint looked perfectly normal - for
lead-free that is - but it had not whetted the resistor leg at all. How
the
hell could that take two hours to go bad, not be responsive at all before
that time, and then when it has gone bad, not respond to twisting, but be
so
tap sensitive that you could make it come and go with a feather? I HATE
lead-free with a passion.

If it ever finds its way into avionics, be afraid, be VERY afraid ...

Arfa




I'm thinking of making a tug-test tool for PbF checking. Probably based on
an automatic centre punch tool latch mechanism but somehow inverted in
operation. How many ounces or grams of pullout tension do you think a 1/3
W
resistor lead/wire link/TO92 wire should resist pulling out , leaded
solder
that is.


--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://diverse.4mg.com/index.htm

I would have thought pretty much to the wire breaking point. How many times
have you hooked a screwdriver or whatever, under a component in order to
unsolder one end, then heated the joint on the other side of the board,
whilst applying pressure to the link / component, only to then have it snap
on you, because you were heating the joint next to the one you were supposed
to be ...

Arfa

 

[N_Cook]

Arfa Daily <arfa.daily@ntlworld.com> wrote in message
news:I2sJn.51965$ER.41189@newsfe07.ams2...

"N_Cook" <diverse@tcp.co.uk> wrote in message
news:ht5c0o$2m0$1@news.eternal-september.org...
Arfa Daily <arfa.daily@ntlworld.com> wrote in message
news:mdlJn.18479$ea4.8777@newsfe29.ams2...

I would have thought pretty much to the wire breaking point. How many
times
have you hooked a screwdriver or whatever, under a component in order to
unsolder one end, then heated the joint on the other side of the board,
whilst applying pressure to the link / component, only to then have it
snap
on you, because you were heating the joint next to the one you were
supposed
to be ...

Arfa

One problem is ,for likes of TO92 and standardised tug , the use of surgical
artery forceps to grip before pulling, too much grip force and you squash
the lead.
I just tried with a board and counter weights on kitchen scales and I would
say I use about 1Kg of tug with thin nose pliers, pulling perpendicular to
the pcb.

What date was the VOX ? I've previously found 2 ,tug test failing, loose
links due to PbF on a 2005 Vox AC30 , AC30CC2X . Found in passing as
otherwise in for valve and intrusive tremolo initiated rumble


--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://diverse.4mg.com/index.htm

>

 

[Colin Horsley]

"Arfa Daily" <arfa.daily@ntlworld.com> wrote in message
news:I2sJn.51965$ER.41189@newsfe07.ams2...


I would have thought pretty much to the wire breaking point. How many times
have you hooked a screwdriver or whatever, under a component in order to
unsolder one end, then heated the joint on the other side of the board,
whilst applying pressure to the link / component, only to then have it snap
on you, because you were heating the joint next to the one you were supposed
to be ...

Arfa

______________________

yep, done that!

Colin

 

[Ron]

On 21/05/2010 13:28, Meat Plow wrote:

On Fri, 21 May 2010 02:20:17 +0100, Arfa Daily wrote:


If it ever finds its way into avionics, be afraid, be VERY afraid ...

Arfa

Come to think of it, lead free solder and volcanic ash look very similar.

Ron

 

[William Sommerwerck]

If it ever finds its way into avionics, be afraid, be VERY afraid...

Shouldn't be a problem. How often are F-15s dumped in landfills?

 

[Jim Yanik]

"Arfa Daily" <arfa.daily@ntlworld.com> wrote in
news:mdlJn.18479$ea4.8777@newsfe29.ams2:

The first is the Warrior amp that I posted on here about, looking for
schematics. None were found, and as expected, the importer ignored my
pleas, so I decided I would spend a half hour on it 'blind'.

It turned out to not be too difficult to get the main PCB out,
complete with heatsinks and back panel. The wiring was long enough to
allow the board to be turned over, without having to disconnect
everything. The fault was that one of the two identical output stages
was behaving as a pretty good half wave rectifier, but only with a
load connected. With no load, an applied sine wave was perfectly
symmetrical at the output terminals, and of similar size to the good
channel. With a load connected, the negative excursions disappeared
almost totally. Nothing was burning, and the the output protect didn't
even fire until the wick was turned well up, which led me to believe
that the problem may well be back in the driver stages or earlier. As
there are two identical amps, I figured that I would start with a few
comparitive resistance checks between channels. Quickly, I found that
at the base pin of one of the driver transistors, I had a reading of
3k or so on the good channel, but open circuit at the same point on
the bad channel. I followed the print back and took another reading
and Lo! - 3k ...

So I went back to the transistor leg - open, but at the joint, 3k. I
tell you, I examined that joint with the strongest light and magnifier
that I have, but you could not see a problem with it. However, as soon
as it was resoldered, 3k on the leg as well, and the amp then worked
normally. This is the problem with lead free. You can no longer spot
bad joints by eye, and they don't behave like conventional bad joints
any more.

The second one was a Vox combo. This one was reported as "goes off
after a while - tap top to get it back". It actually ran for about 2
hours, during which time I thrashed the output stage so hard you
couldn't touch the heatsink, and periodically knocked seven bells out
of it with the butt end of a large philips screwdy. At no time did it
show any signs of intermittency. I was actually on the phone to the
store that it came to me from, to check if they knew the owner, and
whether he was savvy, or a numpty, when it went off. Just like that.
No provocation. You could then lightly tap the top of the chassis just
about anywhere, and it would come and go at will. So easy was it to
make it do it, you would have thought that the joint causing it would
have been really easily spotted. I twisted and wiggled everything I
could, but nothing made it do it, but still the lightest tap, and
there it went.

Eventually, after a frustrating session of blanket resoldering that
did no
good at all, I came to a power resistor standing up off the board. It
was a component that I had previously twisted. This time I pulled it,
and one leg just came right out of the board. The joint looked
perfectly normal - for lead-free that is - but it had not whetted the
resistor leg at all. How the hell could that take two hours to go bad,
not be responsive at all before that time, and then when it has gone
bad, not respond to twisting, but be so tap sensitive that you could
make it come and go with a feather? I HATE lead-free with a passion.

If it ever finds its way into avionics, be afraid, be VERY afraid ...

Arfa

most of the time,when you have an intermittent,if you tap it,you end up
working the joint to a better connection and you don't see the
intermittent.
you have to leave it alone and wait patiently for the IM to show up,then
lightly tap around to find the area most sensitive.

--
Jim Yanik
jyanik
at
localnet
dot com

 

[Jim Yanik]

"William Sommerwerck" <grizzledgeezer@comcast.net> wrote in
news:ht61dl$i4s$1@news.eternal-september.org:

If it ever finds its way into avionics, be afraid, be VERY afraid...

Shouldn't be a problem. How often are F-15s dumped in landfills?

there's a guy who bought a scrapped,"demilled" T-38,with a cracked
airframe,he owned a aircraft maintenance shop and was able to restore it to
flight condition,and he has the only civilian,flyable T-38 jet.
It's the trainer version of the F-5 fighter,the "Mig 28" in Top Gun.

--
Jim Yanik
jyanik
at
localnet
dot com

 

[Meat Plow]

On Fri, 21 May 2010 02:20:17 +0100, Arfa Daily wrote:

The first is the Warrior amp that I posted on here about, looking for
schematics. None were found, and as expected, the importer ignored my
pleas, so I decided I would spend a half hour on it 'blind'.

It turned out to not be too difficult to get the main PCB out, complete
with heatsinks and back panel. The wiring was long enough to allow the
board to be turned over, without having to disconnect everything. The
fault was that one of the two identical output stages was behaving as a
pretty good half wave rectifier, but only with a load connected. With no
load, an applied sine wave was perfectly symmetrical at the output
terminals, and of similar size to the good channel. With a load
connected, the negative excursions disappeared almost totally. Nothing
was burning, and the the output protect didn't even fire until the wick
was turned well up, which led me to believe that the problem may well be
back in the driver stages or earlier. As there are two identical amps, I
figured that I would start with a few comparitive resistance checks
between channels. Quickly, I found that at the base pin of one of the
driver transistors, I had a reading of 3k or so on the good channel, but
open circuit at the same point on the bad channel. I followed the print
back and took another reading and Lo! - 3k ...

So I went back to the transistor leg - open, but at the joint, 3k. I
tell you, I examined that joint with the strongest light and magnifier
that I have, but you could not see a problem with it. However, as soon
as it was resoldered, 3k on the leg as well, and the amp then worked
normally. This is the problem with lead free. You can no longer spot bad
joints by eye, and they don't behave like conventional bad joints any
more.

The second one was a Vox combo. This one was reported as "goes off after
a while - tap top to get it back". It actually ran for about 2 hours,
during which time I thrashed the output stage so hard you couldn't touch
the heatsink, and periodically knocked seven bells out of it with the
butt end of a large philips screwdy. At no time did it show any signs of
intermittency. I was actually on the phone to the store that it came to
me from, to check if they knew the owner, and whether he was savvy, or a
numpty, when it went off. Just like that. No provocation. You could then
lightly tap the top of the chassis just about anywhere, and it would
come and go at will. So easy was it to make it do it, you would have
thought that the joint causing it would have been really easily spotted.
I twisted and wiggled everything I could, but nothing made it do it, but
still the lightest tap, and there it went.

Eventually, after a frustrating session of blanket resoldering that did
no
good at all, I came to a power resistor standing up off the board. It
was a component that I had previously twisted. This time I pulled it,
and one leg just came right out of the board. The joint looked perfectly
normal - for lead-free that is - but it had not whetted the resistor leg
at all. How the hell could that take two hours to go bad, not be
responsive at all before that time, and then when it has gone bad, not
respond to twisting, but be so tap sensitive that you could make it come
and go with a feather? I HATE lead-free with a passion.

If it ever finds its way into avionics, be afraid, be VERY afraid ...

Arfa

 

[Jeffrey D Angus]

Wild_Bill wrote:

What's taken place, I think, which I suspect was intentionally
forced upon most of us, is that manufacturers wanted to lower
everyone's expectations of quality.

I've been watching this "trend" since the '70s.

My opinion is that we as consumers have brought this on
ourselves with the attitude of: "I don't care if it's
crap, I want it now, I want it cheap and I'll be bored
with it within a year anyway."

Although this isn't entirely new. You could be cheap or
shoddy merchandise for as long as they've been bartering
from stuff. It's just that the ability to mass produce
garbage has exceeded our wildest expectations.

Jeff


--
“Egotism is the anesthetic that dulls the pain of stupidity.”
Frank Leahy, Head coach, Notre Dame 1941-1954

http://www.stay-connect.com

 

[William R. Walsh]

Hi!

Shouldn't be a problem. How often are F-15s dumped in landfills?

Well, if lead free solder causes failures, and as a result one
crashes...what's to stop the site from being a landfill?

William

 

[William Sommerwerck]

What's taken place, I think, which I suspect was intentionally
forced upon most of us, is that manufacturers wanted to lower
everyone's expectations of quality.

I've been watching this "trend" since the '70s.

My opinion is that we as consumers have brought this on
ourselves with the attitude of: "I don't care if it's
crap, I want it now, I want it cheap and I'll be bored
with it within a year anyway."

Although this isn't entirely new. You could be cheap or
shoddy merchandise for as long as they've been bartering
from stuff. It's just that the ability to mass produce
garbage has exceeded our wildest expectations.

I think that's only half the truth. I was born in 1947, and the rate of
technological change is at least five to ten times what it was 50 years ago.
ICs and SMTs, inserted by robots, make possible the "cheap" electronics that
can be easily discarded to make room for the next quarter's spasm of
improvements.

 

[Arfa Daily]

"N_Cook" <diverse@tcp.co.uk> wrote in message
news:ht5los$50l$1@news.eternal-september.org...

Arfa Daily <arfa.daily@ntlworld.com> wrote in message
news:I2sJn.51965$ER.41189@newsfe07.ams2...

"N_Cook" <diverse@tcp.co.uk> wrote in message
news:ht5c0o$2m0$1@news.eternal-september.org...
Arfa Daily <arfa.daily@ntlworld.com> wrote in message
news:mdlJn.18479$ea4.8777@newsfe29.ams2...

I would have thought pretty much to the wire breaking point. How many
times
have you hooked a screwdriver or whatever, under a component in order to
unsolder one end, then heated the joint on the other side of the board,
whilst applying pressure to the link / component, only to then have it
snap
on you, because you were heating the joint next to the one you were
supposed
to be ...

Arfa



One problem is ,for likes of TO92 and standardised tug , the use of
surgical
artery forceps to grip before pulling, too much grip force and you squash
the lead.
I just tried with a board and counter weights on kitchen scales and I
would
say I use about 1Kg of tug with thin nose pliers, pulling perpendicular to
the pcb.

What date was the VOX ? I've previously found 2 ,tug test failing, loose
links due to PbF on a 2005 Vox AC30 , AC30CC2X . Found in passing as
otherwise in for valve and intrusive tremolo initiated rumble


--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://diverse.4mg.com/index.htm

It was a Vox Valvetronix combo - one of those things with the built in
digital amp simulator that purports to make it sound like an AC30, or an
AC15, or a Tweed or a 70's Brit amp or an 80's Brit amp, or a dustbin full
of marbles or whatever. I didn't take much notice of what year, but the
board was marked with a PbF symbol. It last crossed my bench two years ago
almost to the day, when the owner had me fit a buffered variable level line
out to the back panel, so at least 2008 and probably a bit before that.

Arfa

 

[Arfa Daily]

"Ron" <ron@lunevalleyaudio.com> wrote in message
news:SpadnQMzyv8qGWvWnZ2dnUVZ8iSdnZ2d@bt.com...

On 21/05/2010 13:28, Meat Plow wrote:
On Fri, 21 May 2010 02:20:17 +0100, Arfa Daily wrote:


If it ever finds its way into avionics, be afraid, be VERY afraid ...

Arfa



Come to think of it, lead free solder and volcanic ash look very similar.

Ron

Cracker, Ron ! LOL !! ))

Arfa

 

[Smitty Two]

In article <mdlJn.18479$ea4.8777@newsfe29.ams2>,
"Arfa Daily" <arfa.daily@ntlworld.com> wrote:

I HATE
lead-free with a passion.

I don't doubt your experiences, and of course this isn't your first rant
about lead-free. I think the early lead-free formulas were inherently
bad, but I think some of the new ones are pretty damn good. I don't mind
working with them at all, and find the "solderability" to be on a par
with lead.

I still use a lot of lead, but some of my customers (who sell to Europe)
specify lead-free. We use Sn96.5Ag3Cu0.5 and have been well-satisfied
with it. I tend to agree with Wild Bill, that manufacturing has been
turned over to the bean-counters, and that the quality issues you're
seeing with consumer products may be due more to shitty practices than
to the abandonment of lead.

 

[Arfa Daily]

"Jim Yanik" <jyanik@abuse.gov> wrote in message
news:Xns9D7F660E7F973jyaniklocalnetcom@216.168.3.44...

"Arfa Daily" <arfa.daily@ntlworld.com> wrote in
news:mdlJn.18479$ea4.8777@newsfe29.ams2:

The first is the Warrior amp that I posted on here about, looking for
schematics. None were found, and as expected, the importer ignored my
pleas, so I decided I would spend a half hour on it 'blind'.

It turned out to not be too difficult to get the main PCB out,
complete with heatsinks and back panel. The wiring was long enough to
allow the board to be turned over, without having to disconnect
everything. The fault was that one of the two identical output stages
was behaving as a pretty good half wave rectifier, but only with a
load connected. With no load, an applied sine wave was perfectly
symmetrical at the output terminals, and of similar size to the good
channel. With a load connected, the negative excursions disappeared
almost totally. Nothing was burning, and the the output protect didn't
even fire until the wick was turned well up, which led me to believe
that the problem may well be back in the driver stages or earlier. As
there are two identical amps, I figured that I would start with a few
comparitive resistance checks between channels. Quickly, I found that
at the base pin of one of the driver transistors, I had a reading of
3k or so on the good channel, but open circuit at the same point on
the bad channel. I followed the print back and took another reading
and Lo! - 3k ...

So I went back to the transistor leg - open, but at the joint, 3k. I
tell you, I examined that joint with the strongest light and magnifier
that I have, but you could not see a problem with it. However, as soon
as it was resoldered, 3k on the leg as well, and the amp then worked
normally. This is the problem with lead free. You can no longer spot
bad joints by eye, and they don't behave like conventional bad joints
any more.

The second one was a Vox combo. This one was reported as "goes off
after a while - tap top to get it back". It actually ran for about 2
hours, during which time I thrashed the output stage so hard you
couldn't touch the heatsink, and periodically knocked seven bells out
of it with the butt end of a large philips screwdy. At no time did it
show any signs of intermittency. I was actually on the phone to the
store that it came to me from, to check if they knew the owner, and
whether he was savvy, or a numpty, when it went off. Just like that.
No provocation. You could then lightly tap the top of the chassis just
about anywhere, and it would come and go at will. So easy was it to
make it do it, you would have thought that the joint causing it would
have been really easily spotted. I twisted and wiggled everything I
could, but nothing made it do it, but still the lightest tap, and
there it went.

Eventually, after a frustrating session of blanket resoldering that
did no
good at all, I came to a power resistor standing up off the board. It
was a component that I had previously twisted. This time I pulled it,
and one leg just came right out of the board. The joint looked
perfectly normal - for lead-free that is - but it had not whetted the
resistor leg at all. How the hell could that take two hours to go bad,
not be responsive at all before that time, and then when it has gone
bad, not respond to twisting, but be so tap sensitive that you could
make it come and go with a feather? I HATE lead-free with a passion.

If it ever finds its way into avionics, be afraid, be VERY afraid ...

Arfa




most of the time,when you have an intermittent,if you tap it,you end up
working the joint to a better connection and you don't see the
intermittent.
you have to leave it alone and wait patiently for the IM to show up,then
lightly tap around to find the area most sensitive.

--
Jim Yanik

Traditionally Jim, I would agree with you for bad joints on leaded solder.
They are predictable, well behaved in terms of tap sensitivity and
sensitivity to heat and cold and board flexing, but above all, for the most
part, readily visible. Lead-free bad joints seem to exhibit no such
tendencies. Their auto-failure and self-recovery often seem to bear no fixed
relationship to temperature, time or the way in which they are disturbed.
The Vox was a good example of that.

It might be argued that the changing of the mature leaded soldering
technology, that was pretty much taped down in terms of 'goodness' of joints
and reliability, for the lead-free technolgy which has taken us back 40
years to the early days of PCB production in terms of reliability, has been
good for the trade because of it bringing more work through the door.
Unfortunately, that hasn't been the case. Whereas I would expect to be able
to find and correct a bad joint on a leaded solder board in a maximum of 15
minutes from putting the item on the bench, with a lead-free bad joint, I
might finish up spending an hour or more on frustrating blanket reworks of
whole areas of joints, using half a reel more of the hateful stuff, because
conventional ways of finding the bad joints no longer work.

If I then tried to charge a proper living wage hourly rate for the job, the
owners would never come back to pick the item up, instead spending their
hard-earned on the latest bigger / better / shinier / cheaper offering from
China ...

Lead-free solder is making items fail much more than they need to, and
rendering repair uneconomic, leading to more equipment scrapping and, with
the best recycling will in the world, more items going to landfill. I wonder
if all the narrow minded inward thinking ecobollox merchants had this in
mind when they came up with their wonderful idea of mandating the use of
lead-free solder as part of their 'save the planet' religion ?

Arfa

 

[Jeff Liebermann]

On Fri, 21 May 2010 10:51:48 -0500, Jeffrey D Angus
<jangus@suddenlink.net> wrote:

Wild_Bill wrote:
What's taken place, I think, which I suspect was intentionally
forced upon most of us, is that manufacturers wanted to lower
everyone's expectations of quality.

I've been watching this "trend" since the '70s.

What happened before the 70's? It's not like designed obsolescence is
anything new. Auto manufacturers were doing that since WWII where you
were expected to buy a new car every two years.

My opinion is that we as consumers have brought this on
ourselves with the attitude of: "I don't care if it's
crap, I want it now, I want it cheap and I'll be bored
with it within a year anyway."

Yep. Blame the victims.

It's really a self fulfilling mechanism. Today's consumers simply
assume that everything they buy is junk and will blow up immediately
after the warranty expires. Why bother paying for quality when
literally everything falls apart or blows up overnight? The only
thing the vendors can compete on is price, resulting in very small
differences in price that can kill or make a product. That also
results in cutting every corner possible, including shoddy soldering,
bitter edge component selection, and designed to fail component
selection.

What seems to be happening is the demise of hand soldering. In the
distant past, it was somewhat traditional to solder mask the large
physical parts, which acted as a heat sink, during wave soldering, and
hand solder them in "touch-up". Component manufacturers have made
heroic attempts to design components that can be properly wave
soldered, but they tend to be expensive. So, to cut costs,
manufacturers seem to be running everything through wave soldering or
vapor reflow soldering machines, including parts that are really are
too massive. Touch-up is eliminated as is burn-in and QA. If it
blows up, by the time the customer returns it, the next generation of
products will be available. That actually worked with tin-lead
solder, but is failing with RoHS solder. The problem seems to be
(i.e. my opinion) that tin-silver solder has a narrower range of
working temperatures than tin-lead. The large physical components
that were previously soldered by hand, simply suck away too much heat
when soldered, resulting in a cold solder joint.

Although this isn't entirely new. You could be cheap or
shoddy merchandise for as long as they've been bartering
from stuff. It's just that the ability to mass produce
garbage has exceeded our wildest expectations.

Yeah, but you probably couldn't afford it if everything were quality
merchandise.

Anyway, cease complaining. Your test equipment collection is about
the same age as mine and belongs in a museum. It is possible to build
reliable and long life electronics. Just don't expect that from
consumer electronics.



--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

 

[N_Cook]

Jeff Liebermann <jeffl@cruzio.com> wrote in message
news:48idv5teiqm39pfl1dtmc9f4ko3qm6bmdl@4ax.com...

On Fri, 21 May 2010 10:51:48 -0500, Jeffrey D Angus
jangus@suddenlink.net> wrote:

Wild_Bill wrote:
What's taken place, I think, which I suspect was intentionally
forced upon most of us, is that manufacturers wanted to lower
everyone's expectations of quality.

I've been watching this "trend" since the '70s.

What happened before the 70's? It's not like designed obsolescence is
anything new. Auto manufacturers were doing that since WWII where you
were expected to buy a new car every two years.

My opinion is that we as consumers have brought this on
ourselves with the attitude of: "I don't care if it's
crap, I want it now, I want it cheap and I'll be bored
with it within a year anyway."

Yep. Blame the victims.

It's really a self fulfilling mechanism. Today's consumers simply
assume that everything they buy is junk and will blow up immediately
after the warranty expires. Why bother paying for quality when
literally everything falls apart or blows up overnight? The only
thing the vendors can compete on is price, resulting in very small
differences in price that can kill or make a product. That also
results in cutting every corner possible, including shoddy soldering,
bitter edge component selection, and designed to fail component
selection.

What seems to be happening is the demise of hand soldering. In the
distant past, it was somewhat traditional to solder mask the large
physical parts, which acted as a heat sink, during wave soldering, and
hand solder them in "touch-up". Component manufacturers have made
heroic attempts to design components that can be properly wave
soldered, but they tend to be expensive. So, to cut costs,
manufacturers seem to be running everything through wave soldering or
vapor reflow soldering machines, including parts that are really are
too massive. Touch-up is eliminated as is burn-in and QA. If it
blows up, by the time the customer returns it, the next generation of
products will be available. That actually worked with tin-lead
solder, but is failing with RoHS solder. The problem seems to be
(i.e. my opinion) that tin-silver solder has a narrower range of
working temperatures than tin-lead. The large physical components
that were previously soldered by hand, simply suck away too much heat
when soldered, resulting in a cold solder joint.

Although this isn't entirely new. You could be cheap or
shoddy merchandise for as long as they've been bartering
from stuff. It's just that the ability to mass produce
garbage has exceeded our wildest expectations.

Yeah, but you probably couldn't afford it if everything were quality
merchandise.

Anyway, cease complaining. Your test equipment collection is about
the same age as mine and belongs in a museum. It is possible to build
reliable and long life electronics. Just don't expect that from
consumer electronics.



--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

My suspicion it is more to do with tinpest rather than lead free solder. A
layer of 100 percent tin tinning of all leads. Often on removing failed
joints , by pulling, not desoldering, you can see the dusty grey surface of
presumably tinpest .
Then volume change (27 percent ?) to the tinpest allotrope of tin and its
insulation rather than conduction causes the electrical break. Mismatch
thermal expansion coefficients don't seem t be problematic

http://www.boulder.nist.gov/div853/lead_free/part1.html#%201.12.
etc on
http://www.boulder.nist.gov/div853/lead_free/props01.html