On 01/10/2011 11:54, Marc Nicholas wrote: > On Fri, Sep 30, 2011 at 4:13 PM, Dwayne Reid wro= te: >> At 02:02 PM 9/30/2011, Marc Nicholas wrote: >> >>> Apparently this one: >>> >>> http://www.dealextreme.com/p/mechanics-soldering-paste-50g-7952 >>> >>> Is 63/37....good for stencils....and works well. Alas, no lead-free :-/ >> Excellent! Many thanks! >> >> 63/37 is exactly what I want. We build projects for mostly >> industrial users who specify that we are to avoid lead-free solder. > Wow....I didn't know people *choose* to have the lead, but I guess > there was a reason why it was in there in the first place ;) > Because it works better. If not for inclusion of PCBs in RoHS laws then almost no-one would use=20 lead free solder. Pure tin is the worst.. Brittle, poor flow, more=20 bad/dry joints, more prone to tin plague if any nearby gold, grows=20 whiskers that short tracks. Lead doesn't just lower the melting point but improves the soldering in=20 lots of ways. The "best" lead free are still not really as good as Tin/Lead. The=20 minimum is Tin with some silver. But even the Tin/Lead solder a little silver helps reduce leaching of=20 silver on chip capacitors and a little copper can help too. --=20 http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .