[sdiy] No-lead leads

[harrybissell]

What I have read indicates that manufacturers are 'aware' that there is an
issue and they are trying to put the best possible spin on it.  Time will tell.

The tin-lead (solder) plated parts solder well because the solder coat melts.

I read a study (done by TI iirc) complete with microscope photos that suggests
that their lead-free parts should have a life of eight years once the package
is
'open' and more if they are controlled well. They are saying 'eight years in a
warehouse after opening' ... your results may vary.

It turns out that a major cause of the contamination is from sulphur. THAT
comes
from keeping your parts in a damp cardboard box in the basement. If you are
keeping
them in, lets say... Tupperware or Rubbermaid etc you should have better
results.

H^) harry

Seb Francis wrote:

> harrybissell wrote:
>
> >No Problem soldering them, Ian
> >
> >try soldering them in a couple years :^P
> >
> >H^) harry   (Pb forever)
> >
> >
>
> Hi Harry & anyone else who has some knowledge of this Pb-free stuff,
>
> Is it really true that non-Pb parts won't be usable after a couple of
> years?  Is this true for all types of process (e.g. baked matte tin
> plating)?
>
> This would be a real shame - it takes me a long time to get through 100
> resistors, especially the more obscure values.  Am I really going to
> have to bin them after a relatively short time?  Is this just
> speculation, or have some real tests been done over long periods of time?
>
> I'm puzzled because I've seen this problem mentioned before on this list
> but it goes against what most manufacturers seem to be saying
> .. a quick google turned up the following quotes from various
> manufacturers amoung the first 10 hits:
>
> "Shelf life remains the same as for current SnPb-plated products."
>
> "As of today we are not aware of any differences regarding shelf live or
> solderability (moist termination) between lead-free and lead-containing
> terminations. Generally shelf live greatly depends on the store
> conditions and environmental influences (temperature, humidity)."
>
> "No. Guaranteed shelf life remains the same as for current SnPb
> products, except for the exceptions mentioned referring to MSL level."
>
> "Is the shelf-life of "lead-free" components reduced because of
> lead-free plating?
> Unlikely, in fact it could well be improved, as tin has a slower
> oxidation characteristic compared to tin / lead alloy."
>
> "Are there any changes required in device storage conditions or shelf life?
> No."
>
> The only times I have read that shelf life is worse is when talking
> about PCBs, and even then they are talking about automated (e.g. reflow)
> soldering.  I can understand that an old PCB or component might get a
> bit more difficult to solder with age, but with a decent flux core
> solder and a couple of seconds with an iron surely the oxide layer will
> dissolve?
>
> Seb (who did just buy a large reel of Tin-Lead solder just in case the
> new stuff's not so nice to use!)