A process of making a base of a shock-absorbing front fork for a bicycle, includes the steps of winding pre-pregs around an upper section of each of two cured straight tubes to form a bridge having a foamed core therein, and placing the two straight tubes and the bridge in a mold and heating the mold for curing the bridge such that the bridge and the straight tubes are connected integrally. While the disk is rotated unidirectionally, the electron beam is repeatedly deflected in a figure 8 pattern, in which the electron beam is deflected toward the next deflection initiation point in the radial direction at track edge portions, such that the deflected directions toward the inner periphery of the disk and toward the outer periphery of the disk intersect each other. The sulfur-containing compounds can be partially oxidized to sulfoxides andor sulfones prior to or during the extraction step. In the conventional art, there is the problem that the HDD main body is caused to fall carelessly in attachment working in which the HDD main body is mounted to a housing case such that the HDD main body drops into a housing case in a vertical direction.