Between each solder application simply wipe the working area of the bit clean on a damp cellulose sponge to remove the dross and oxides that will accumulate and add small amounts of fresh solder to the bit as needed. A gentle wiping is all that is required and care must be taken not to over wipe the bit, because oxidation will occur on the surface quite rapidly if all of the solder has been removed. Once this oxidation occurs it becomes difficult, or even impossible for solder to wet to the bit. It then becomes necessary to properly clean and re-tin the bit in order to regain the appropriate wetting action required for adequate performance. When you have finished the soldering application, you should wipe any contaminates from the bits surface and add a small amount of fresh solder to it before allowing the iron to cool. This layer of solder ensures protection from oxidation of the bit between uses and will help to extend the bits working life.
Courtesy of American Beauty Tools
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