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Eeyore Eeyore is offline
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Default So what's the truth about lead-free solder ?



N Cook wrote:

Eeyore wrote

I just came across this too.
http://en.wikipedia.org/wiki/Tin_pest

" At 13.2 degrees Celsius (about 56 degrees Fahrenheit) and below, pure
tin transforms from the (silvery, ductile) allotrope of beta-modification
white tin to brittle, alpha-modification grey tin. Eventually it decomposes

into
powder, hence the name tin pest."



So when I pull , with just finger tension, a component lead through what was
a lead-free solder joint only a year or so before and there is a grey
powdery looking surface to the lead where it had been inside the solder
joint - is that "tin pest" ?


It could well be I suppose. Here's the problem, we're in 'uncharted territory'
here because the EU insisted on going down this path before the science was
well-established. Document it. It has serious implications for the classic
practice of keeping MI gear in the van / truck, in the (unheated) garage etc.

I'd love to see the idiots at the Commision in Brussels forced to eat humble
pie. It's about time that Emperor Barroso's new clothes were seen for what they
are.

Graham