Re: Lead Free (was Re: CD MMC caps from DigiKey...)

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: Sparktron01@xxxxxxxxxxx 

Terry, all

There are other issues with "lead free" soldier, particularly with
Tin amalgams:

Tin whisker growth  leading to latent/delayed PCB failure is a major issue.
Dense board traces (and high differential voltages) seem to promote
PCB failures.  The first one can be designed out to some degree, the
second one is dam.. near impossible to completely remove in the
OLTC / SSTC realm...

See URL below or google "Lead Free""Tin Whiskers"
http://www.reed-electronics.com/electronicnews/article/CA511404.html?industryid=22121

Only got 41.3K worth of hits    :^)

Regards and Merry Christmas (no pun)

Dave Sharpe, TCBOR/HEAS
Chesterfield, VA. USA

 -------------- Original message ----------------------
From: "Tesla list" <tesla@xxxxxxxxxx>
> Original poster: Terry Fritz <vardin@xxxxxxxxxxxxxxxxxxxxxxx>
>
> Hi Skip,
>
> There is a massive push to remove lead (and other nasty metals) from
> all consumer items.  Thus you will see "lead free" all over when
> looking for electronic components now.  China and Nigeria finally
> found out why we were happy to give them all that old electronics
> stuff for free.  They used to laugh at the lead contamination risk,
> but they have definitely stopped laughing now!!  So lead is now on
> the way OUT big time for mass produced consumer stuff...
>
> I have used tin/silver/copper and some others lead free hand
> soldering wire and they suck compared to using good old tin-lead for
> hand soldering.  Factories can play with processes and go though
> hoops to get it all to work in wave and IR soldering, but I could
> never even give my dumb roll of lead free wire solder away....  I was
> trying to make one of my little products lead free about two years
> ago but had to give that up since the hand soldering was too hard.
>
> Tin lead solder flows really well and just works really good and that
> is why it has taken so long to replace it.  Tin-Lead also has a
> fairly low melting point compared to the newer types that require
> components to withstand far higher soldering temperatures.  Lead free
> needs to be HOT and you do need a temperature controlled soldering
> iron.  Of course, the added heat make the usual problems with no
> clean or aqueous clean solder fluxes that much worse...
>
> I could go on for a few days telling you all about it, but lead just
> works really well compared to the substitutes.  Fortunately, the
> threat of lead contamination killing us all has finally forced Japan,
> EU, and US to change now.  The US actually tried to do it about a
> decade or so ago but the technical problems then were too
> daunting.  In a year or so, almost everything you buy electronic will
> not contain lead or the RoHS nasties.
>
> I think lead hand solder will be around for awhile though.  The lead
> free does work though if your really have to use it.  For Tesla
> coiling, it should not be a big deal at all aside from the DRSSTCs
> that will see some part component costs go up for awhile (or there
> will be big sales trying to get rid of left over lead stock ;-)).  If
> the wire solder goes away, hopefully the components will be able to
> take the added heat needed for lead free solder.  I like to think
> that after years of hybrid and general electronic work that I am a
> super good solderer, but lead free hand solder is a real bear to work
> with...  You can just forget trying it with SMT parts...  Hopefully,
> they can figure out something to make the lead-free solder wires
> better, I don't recommend getting any right now until they figure it
> out or you will just keep trying to give it away to get rid of it 
like I did.
>
> Cheers,
>
>          Terry
>
>
> At 05:52 PM 12/15/2005, you wrote:
> >We use lead free solder here for plumbing.  Why not
> >electronics?  Instead of Tin and Lead, it is Tin and Antimony.
> >
> >Skip
> >
> >At 07:21 PM 12/15/2005, you wrote:
> >>-Phil LaBudde
> >>(what do they use to wire things together over there in Europe?
> >>Lead-free solder?)
>
>
>