In order to determine the strength of these practice welds, the following test can be made:
Clamp one side of the cooled test piece into the jaws of a vise, with the weld-bead facing outward, about
3/16 inch and parallel to the top of the jaws. Cover with a loose cloth to prevent injury due to flying pieces.
A blow with a hammer on the weld side will usually break off the top piece. If the weld is a good one, each
broken piece will retain some portion of the welding rod, with the break occurring through the body of the
rod. In an exceptionally good weld, the break will occur through the base material. This indicates a weld
strength of 100%,
or close to it, of the strength of the base material. If the weld was overheated at any point, the pieces will
usually separate at that point, and the browned portion will be readily visible, indicating the typical poor
adhesion of overheated areas. If the rod or base material was under-heated, the break wiII also occur
where the unheating occurred. NOTE: If there were no overlaps at the top of the beveled edges, the weld
would normally break along the plane of the bevel. This demonstrates the necessity for filling welds.