"matt weber" wrote in message
...
On Thu, 20 Oct 2005 15:15:46 GMT, "Frank Dresser"
wrote:


They have banned lead, but largely because of the fumes from the
production of the products,

I think the various lead bans are intended to keep lead out of the air and
drinking water. That is, no more lead in gasoline and no more lead based
plumbing solder. Much nasiter stuff than lead is used everyday in
industrial processes, and there aren't many problems. I'd think government
standards for industrial lead use would have to do more with exposure,
ventilation and training, rather than an outright ban. But I don't know,
and you might be right.


Pure tin solders have some very
interesting problems of their own, and it has been a very unpleasant
experience for the Military. Under conditions not well understood, the
tin will grow crystals sometimes, and the crystals can and do create
new connections that were never intended, usually with less than
desireable consequences...

Yep. Tin whiskers. Check out:

http://nepp.nasa.gov/whisker/

Interestingly, one of the recommended ways to reduce tin whiskering is to
avoid using pure tin plating and use tin-lead plating, instead.

Frank Dresser