Abstract: A scale is connected with the vertically movably tracer so as to provide an indication of the surface of the tracer abutting the underside of a stem of a T profile. The scale is adjustable relative to the tracer by an amount equal to one half the stem width and cooperates with an indicator of the center line of the drill of the drilling unit.

Abstract: A drilling machine for working on longer workpieces, such as steel profiles having a fixed, non-variable frame. The machine includes a horizontal machine underpart arranged transversely to the longitudinal axis of the workpiece, two vertical side parts attached to the underpart ends and a horizontal upper beam attached on the side parts, and three drilling units each having a drilling spindle, a gear and a motor. The drilling units are shiftable in a plane parallel to the frame. The first drilling unit has a horizontal drilling spindle and is attached to a side part to the side of the workpiece; the second drilling unit has a second spindle arranged horizontally to the first drilling unit and on the opposing side of the workpiece; and, the third drilling unit has a vertical spindle and is attached to the upper beam. The second drilling unit has its horizontal drilling spindle on a horizontally driven carriage provided with lower wheels and upper wheels.