 From the late 19th century until the 1970s, this method of frame construction was favored because the lower temperatures of brazing (silver brazing in particular) had less of a negative impact on the tubing strength than high temperature welding, which can seriously weaken many steel alloys.Brazing thus allowed relatively thin walled, lightweight tubes to be used without loss of strength.However, recent advances in metallurgy have created steel tubing that is not adversely affected (or may even be improved) by high temperature welding.