Typical of news reports, the media seems to concentrate on the
sensational. Certainly, the proliferation of throw-away consumer
electronics ending up in landfills is a grave concern for adding to the
lead content of our environment, and I applaud the efforts to keep that
to a minimum.
But, consider just how many ham rigs end up in landfills - not many in
my opinion. We have many avid collectors of old ham gear and in many
cases, boat anchors are a prized possession. Lead-free solders are a
real salvation for manufacturers (BTW, the K3 and later K2 boards are
RoHS compliant) who can implement the lead-free techniques. For
personal soldering, I chose to use my 63/37 alloy solder, and I know
that little of it will ever find its way to the landfill.
The 'tin-whiskers' problem is one that exists mainly at the chip level.
The migration of conductive paths between pins that can be soldered by
hand techniques is *not* a problem because the 'whiskers' typically do
not extend that far. It is a problem inside the chips where distances
are measured in angstroms rather than in fractional inches or millimeters.
Bottom line - while you may eventually see this 'tin whiskers' problem
resulting in IC failures, it will not be apparent in the soldering that
we hams do, even with the fine pitch SMD devices.
73,
Don W3FPR
Dick & Judy Lamb wrote:
A recent Associated Press article discusses a topic that's received
much attention on this reflector: the negative consequences of
environmental restrictions on lead in solder for electronics. The
primary concern the article mentions is that tin, when in an alloy
absent of lead, promotes the spontaneous growth of tiny "tin
whiskers" that can short traces in circuit boards. Failures stemming
from whiskers are cited in electronics ranging from consumer items to
satellites. The article as it appeared in my local newspaper had a
very dramatic photo of whiskers on a tin-plated tuning capacitor.
http://www.theworldlink.com/articles/2007/10/06/news/doc4707c03901b23958789121.txt
I should note, for newcomers to the reflector, that Elecraft's list of
approved solders specifically cautions against using any that are lead
free:
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