a build up of deposit along the seam and there is very little if any warpage with the retainer and bearing element 27 welded to the cutter 31 the cone cutter 31 is rotatably locked upon the bearing pin 14 the bearing pin 24 with the cone cutter 31 rotatably locked thereon is now ready for assembly on the arm 23 a passage is machined into the arm 23 the passage extends from the shirttail 30 through the arm 23 to the cutter receiving surface the annular seal 26 is positioned around the bearing pin 24 and seated in the seal recess in the annular retainer and bearing element 27 the mounting portion of the bearing pin 24 is positioned in the passage in the arm 23 the annular mounting surface of the mounting section of the bearing pin 24 and the annular mounting surface of the passage in the arm 23 form a seam the bearing pin 24 is welded to the arm 23 by fusing the annular mounting surface of the mounting section of bearing pin 24 to the annular mounting surface of the passage through arm 23 this is accomplished by directing a beam of high velocity electrons into the seam to fuse the bearing pin 24 to the arm 23 the beam of electrons is produced by an electron beam gun and the beam is caused to move in the plane of the seam by relative movement between the beam and the seam the beam has a high intensity 10 kw mm 2 and a high power capacity 60 kw the welding operation is conventionally carried out in a vacuum chamber however it is to be understood that a laser.