On 2015-Aug-01, at 2:38 PM, Paul Koning wrote: >> On Aug 1, 2015, at 5:24 PM, Robert Jarratt <robert.jarr...@ntlworld.com> >> wrote: >> >> PS A related question. I struggled somewhat with the Weller Magnastat No. 8 >> tip, when trying to solder leads to the ground plane, I could not get the >> solder to stay molten very long. I was using lead-free solder, its melting >> point is much lower than the temperature which a No. 8 tip reaches. The iron >> is 50W. Clearly the ground plane was taking heat away, but is it a problem >> with the tip not being hot enough, the iron not powerful enough, or perhaps >> some operator error? > > Politically correct solder is harder to use and has a higher melting point. > I asked one of the professionals at the office about it; her answer was to > avoid it unless it was required for the job. In other words, for hobby use > and for anything else that isn’t sold, stay away from it. Modern components > are perfectly happy being soldered with real solder, even though they are > made lead-free. > > I followed that advice and was very happy with the outcome. > > Meanwhile, 50 watts isn’t all that much when you have a major heat sink. A > ground plane may be enough to give you trouble, but I suspect it’s the use of > lead free solder that’s the real issue.
As an example, I was trying to solder on the ground-plane of a 1970s (i.e. leaded everything) Heath digital tuner recently (double-sided ground plane on the PCB). Old Weller 48W/700F/mag-temp-switch iron was not up to it, would only melt in immediate proximity to the tip.
