Chris Jones wrote in message
...
N Cook wrote:

Do you mean tin pest or whiskers? I would have thought that the edges
would
be the worst place for whiskers to sprout from.

As for solderability, I would have thought that if the pins are exposed to
a
sufficient quantity of sufficiently hot SnPb solder for a sufficient time,
then the tin would dissolve into the solder, like fine copper wire has an
annoying tendency to do. If overheating of the semiconductor device is a
risk, then perhaps it could be done in a couple of goes, allowing to cool
in between. The resulting tin-rich solder could either be removed and
replaced with fresh solder, or just diluted with more fresh solder.

I'm sure there would be plenty of people interested if you find a good
technique for small-scale use.

Chris


With the sort of stuff I deal with, geometry-wise, tin whiskers have no
relevance I would have thought.
It is that film of tin , all lovely mirror shiney when new turning to grotty
dusty grey (tin pest) , expanding in the process , and physically pushing
the solder away from any conduction maybe only 2 years down the road.
I am not sure just heating legs with solder would affect the integrity of
that initial tin film without some sort of mechanical intrusion while hot
and mixing.


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Diverse Devices, Southampton, England
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