Abstract: A method for rounding a fixture receiving end of flat-oval tubing having internal transverse webs is disclosed. The webs are severed and the ends of the web severance are then reformed to reduce stress concentration in preparation for further working. The end of the tubing is then belled out to a cylindrical shape where the webs have been severed by inserting a male arbor which causes the inner diameter of the tubing to conform to its round cross-section. It is preferred that the arbor be grooved to accept registration with the severed webs. The outside diameter of the fixture end of the tubing is reduced by swagging with a mandrel to the extent necessary to form a standard size for which equipment is readily available. This method provides flat-oval tubing with ends that easily accept valves, fittings, and other connections as needed.