be added the parts are clamped in this position in a jig which is then mounted in the vacuum chamber of a conventional electron beam welding machine not shown after the chamber of the welding machine is evacuated a high energy electron beam simulated by dashed line 48 in fig3 is projected into the interface between the shirttail and pin base portion to melt the facing surfaces in the interface zone and weld the parts together the beam is moved to cover the entire circumference of the interface zone and the beam energy is varied to control welding depth corresponding to the varying axial length of the zone around the circumference of the pin preferably the penetration depth i e in the direction of the electron beam of the weld is extended into flange 38 to insure that the entire interface of the shirttail and bearing pin base portion are welded together for maximum strength the approximate location of the inner or terminal end of the weld is indicated by dashed lines 49 in fig3 the presence of flange 38 enables the operator to continue the weld slightly beyond the end of the desired welded interface rather than attempting to control the electron beam to extend the weld only to the exact end of the interface conventional electronic equipment is used to control the movement lateral speed and energy of the electron beam it is also practical to rotate the assembled parts with respect to a stationary electron beam if desired when the welding operation is completed the vacuum chamber is brought up to atmospheric pressure and the.