If you don't use rosin... (Score 2, Interesting)

... wouldn't that prevent the problem of circling solder? It seems to me that the rosin wouldn't be necessary in space because oxidation doesn't need to be prevented. NASA says that "hydrogen and helium are the prime components and are only present at extremely low densities" in space. Thus, the only reason I could see rosin being necessary is if the soldering would take place inside the space vessel. Otherwise, it seems to me that rosin could be removed from solder that is to be used on the space-side of these vessels.