Abstract: This application involves an adjustable support structure for positioning an exothermic welding mold or other article, i.e., pipe, angle iron, etc., adjacent a surface comprising: an attaching member designed to be removably affixed to a supporting surface; a vertical support member, adjustably mounted on said attaching member; a horizontal support member, adjustably mounted on said vertical support member; an adjusting rod, adjustably mounted transverse to said horizontal supporting member; wherein said adjusting rod includes a member for rotating the adjusting rod thereby imparting a reciprocating motion to an abutting plate mounted on one end of the adjusting rod and said abutting plate being designed to releasably engage an exothermic mold or other article, i.e., pipe, angle iron, etc., adjacent a surface to be welded.