Arfa Daily wrote in message
...

"Meat Plow" wrote in message
...
On Fri, 22 May 2009 01:49:59 +0100, "Arfa Daily"
wrote:


"Eeyore" wrote in message
...


whit3rd wrote:

On May 21, 2:59 am, "N_Cook" wrote:
Obviously I've come acros melting/burning, starting from bad
connection
arcing , but not this amount of damage, so am requesting other
opinions.

Burning right thru the pcb for 1/2 inch around the L pin of the
IEC,
melting
of the plastic of the IEC above the burning and even the linecord
plug

Yep, ring crack around a power solder connection, generates lots of
heat.

Possible. A victim of lead-free soldering ?
http://en.wikipedia.org/wiki/Tin_pest

Note that pure tin solder degrades below 13C. Yes that's right. And
turns
to dust.
Adding a little copper doesn't stop it but slows it some but not
enough.

The EU Commission should be strung by their necks from lamp-posts for
being a
bunch of technically ignorant ****s. Why do they think lead was used
in
solder in
the first place ? For fun ?

Graham


Just what I've been saying since they first mandated the hateful stuff
....

Arfa


Glad I stockpiled enough 60/40 to last me a lifetime. I could probably
sell it on Ebay for an exuberant price one day :-)

This Tin Pest stuff sounds like a serious problem though.

60/40 is still readily available here in pretty much all of the varieties
that it always was - I got a new roll just a couple of weeks ago. What was
interesting though, is that they have jacked up the price to match -
almost
exactly - the cost of the dreaded lead-free, which up until recently, was
like 50% more expensive.

Arfa



Do you know the most authorative source/group, academic or industry
expert/s, on tin-pest, lead-free solder, in-service degradation of solder in
connjunction with temperature and vibration. ie those issues, as distinct
from tin whiskers aspect that seems to have more coverage.


--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/