Jim Thompson wrote:

I have never before owned a soldering station with a temperature
control. What's the best setting (60%Sn/40%Pb)?
Whew, glad you are coming in from the dark ages! I generally use 650 F
for general work, but in cases of really fragile boards or parts, will
turn it down to 600 F. 63/37 solder melts at 424 F, but you need to
account for thermal resistance in the tip and heat sink effects at the
joint. Also, it is often better to run the iron a bit hotter and get
the soldering work done quickly than run the iron at the bare minimum
temp and have to heat the joint for a LONG time to get the solder to melt.

For lead-free work, I have to run the iron at about 700 F for light
stuff, and 750 where heavy traces and power components sink the heat away.

Jon