In conventional fabrication manufacture the thickness of the steel plates are often determined by the metal section required at the weld joints. The subject apparatus and method overcomes this problem by selectively forming a thickened edge along the edge of a thinner steel plate which can now be limited to the thickness required to withstand the stresses on the fabrication. The thickened edge is produced by passing a plate supported on a table through a forming apparatus having a forming roller. The table is movable in an oblique direction relative to the plate so that the shape of the thickened edge may be varied. The forming apparatus and table are automatically controlled to produce a thickened edge of a desired shape intermittently or continuously along a linear or non-linear edge of the plate.