tack weld noun 1verb 1forms 3 noun1 •A small, isolated weld used to position and secure pieces of work (typically, in preparation for the final weld).A large number of very small tack welds should be used on thin metal sections, while a few larger tack welds may be used for thicker metal parts. — 2011 verb1 •To position and secure pieces of work using small welded joints at isolated points (typically, in preparation for the final weld).Three rolled sheets are clamped together and to a form and are then tack welded into place. — 1923 formstack welded · tack welding · tack welds
