At 9:06 PM -0500 1/15/07, Chuck Harris wrote: >Michael Sokolov wrote: >> Hello again, >> >> Thanks to everyone who has replied to my query! >> >> I have a few additional questions though: >> >> 1. What about the tin whiskers? Will they be eliminated by using SnPb >> solder, or will they always remain a potential problem when one is >> forced to use a Pb-free part? > >No, because the lead solder only wicks up the leads so far. The crinkles >made by the crystalization make perfect launching points for whiskers.
I'd like to chime in here... I would suppose that the tin whisker problem, caused by pure Sn on the surface of the component lead, ought to be mitigated by thoroughly coating the component lead with PbSn solder. That's just what the chip makers used to do before they had to get the Pb out. I hand-solder SMT parts using water-soluble liquid flux and PbSn solder, so the leads get a good coating of Pb. I guess we'll see how many years they survive. The purpose of the RoHS regulations as I see it is to eliminate the vast majority of lead in the waste stream caused by the fact that *billions* of disposable elctronic thingies are tossed into landfills each year since they're too cheap and too complex to repair. Hobbyists do not figure in to the numbers we're talking about. Whether it's a good idea to make billions of electronic thingies per year is another question, but it appears to drive our economy judging from the amount of advertising space devoted to the gadgets. I stil haven't tossed my 2 year old broken DVD player that needs a new motor worth a dollar but unavailable due to planned obsolescence. Shame on you, Toshiba! -- --David Forbes, Tucson, AZ http://www.cathodecorner.com/ _______________________________________________ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
