Abstract: Metal parts are spot welded together. To prevent corrosion of the parts a thixotropic, non hardening, corrosion resistant material including a solvent and having a negligible gravity flow at temperatures less than about 400.degree. F to 440.degree. F and forming a heat insulating coherent gel when burnt is used between the plates. The material is known as Anchor Tuflex #23. The parts are clamped and a pressure, higher than a welding pressure that would be used without the material is used to squeeze out the material. The high pressure is continued during welding. After welding continued pressure, is applied during cooling.

Abstract: A method of joining first and second sheet metal parts along a common seam formed from a first surface on the first part and a second surface generally matching the first surface and on the second part. These surfaces define therebetween random spaces of variable thickness when the surfaces are assembled in a generally abutting coextensive relationship.