"Arfa Daily" wrote in message
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"ian field" wrote in message
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"Arfa Daily" wrote in message
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"ian field" wrote in message
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"Arfa Daily" wrote in message
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"mc" wrote in message
.. .
Given that it's desirable to do repairs with the same type of solder
as was used originally, in order to avoid alloy mixing or partial
melting problems...

(1) How do I recognize lead-free solder when I see it?

(2) What temperature should I set my iron to, when working with SnSb
or SnAg solder?

Thanks!


It has been recommended by the creators of the half-arsed RoHS
directive, that manufacturers mark their boards with the alloy that
has been used. To date, I think I have probably seen about 2 or 3. In
general, boards made with lead-free, look as though every joint is bad
( and often, this is pretty much the case !! ). Instead of the joints
having a shiny appearance, and being domed or meniscus-shaped, they
are dull and grey, decidedly 'crystalline' looking, and tend to be
volcano-shaped, with straight sides.

snip

Any chance the half-arsed RoHS directive was thought up by the stuck up
gits who pepper the countryside with 12bore lead shot?

Most shot used in clay shooting is no longer lead, I seem to recall.
Anyway, the point is that if it is, it is not recycled, so remains lying
where it is. Solder accounts for less than 1% of the world's mined lead,
over 80% going to car battery manufacture. The car battery industry have
managed to organise virtually 100% safe recycling, so are allowed to
carry on using lead on this basis, and the contention that there is no
suitable alternative. With the coming of the WEEE directive shortly, end
of life electronic equipment will have to be safely recycled in much the
same way, so where's the difference ? If the car battery people can do
it, I'm sure that the electronic people can also do it with less than
1/80th the volume.

The point about the RoHS directive as it stands with regard to leaded
solder, is that it is forcing a changeover from a mature, tried and
tested technology, which had reached the point of almost perfect
reliability, to a less than satisfactory alternative, with at best,
woolly reasoning to try to justify it. This is well understood by such
people as the US military, who refuse to use the stuff, the avionics
industry, who have obtained exemptions, and the medical instrument
industry, likewise. Any ecological advantage from the poisoning angle,
will probably be outweighed in the long run by the additional energy
budget worldwide to run all those solder production lines and hand
soldering irons 50 degrees hotter, and all the extra recycling brought
about by electronic equipment being junked earlier due to owners getting
fed up with all the intermittent problems from bad joints ...

Just keep your fingers crossed that avionics are not finally forced down
that route, coz that'll be the day that I stop flying.

Arfa


Some good points there, I didn't know lead was no longer used for 12bore
shot - any idea what they use instead?

Regardless of the WEEE directive, lead was originally mined out of the
ground and one way or another it will eventually end up back there, also
I had always held the opinion that the common solder alloys were
substantially less toxic than lead on its own, if this is true then the
manufacture of lead/tin solder actually reduces the availability of lead
wherever it ends up at end of life.


I have a friend who owns a clay range. A few years back, there was a big
thing locally about shot from his range ending up in a wheat field behind.
This also lead to complaints on the noise issue. As far as I recall, they
changed over to a different cartridge, that has a non-lead shot content,
and a lower velocity powder charge, which cuts down on the noise, making
more of a soft whumph noise than the previous sharp bangs. I haven't seen
him for a while, nor been to the range, so I don't know what the effects
of this have been on the sport, but I will try to find out, if you like.

I think that the issue with ' out of the ground / back to the ground '
that's usually quoted, is that it came out of the ground as a naturally
occuring ore, but goes back as refined lead. But I'm still not convinced
that this whole thing is not just an eco smokescreen, keeping beaurocrats
in a job. I'm sure that there are much more hazardous substances getting
into the eco system, than lead from solder.

Arfa

Arfa


If you can find out that would be great - I thought I overheard somewhere
that they merely coated the lead shot with bismuth.