BENCH TIP FROM ALAN REVERE
Soldering is a delicate and sometimes difficult process--- especially when you need to solder very close to a previous solder seam. Without care, you can easily melt that prior seam and dislodge the parts.
One solution is to drop down a temperature level for the second seam, but that will limit further soldering to even lower temperatures. Another reason for staying with higher-temperature solders is that the color of lower-melting point solder usually does not match the metal as well. Fortunately there are other ways to deal with multiple solderings in close quarters, which enable you to work at the same solder level.
Remember that solder flows only on clean surfaces; it doesn’t work well on dirty or oxidized areas, nor on surfaces that don’t have flux (a cleaning compound). So you can discourage seams from flowing by intentionally making them dirty. A good way to do that is with an anti-flux, such as yellow ochre, rouge, grease, or even melted rubber; all of these compounds inhibit solder flow.
However, one tangible technological benefit for bench jewelers is correction fluid, the kind used in offices all over the world. Coming with it’s own applicator in a jeweler’s size bottle, this solution significantly decreases solder flow. (Note: Water-based correction fluids are less toxic than those that are solvent-based. In any event, after applying the liquid, let it air dry in a well-ventilated area and do not inhale the fumes. By applying correction fluid to previously soldered joints, you can solder additional seams nearby and still maintain the integrity of the piece.