Jig for forming sealant layer for lightning protection fastener, method for forming sealant layer for lightning protection fastener, and wing of aircraft

A jig for forming a sealant layer for a lightning protection fastener, the lightning protection fastener comprising a fastener member that passes through and fastens a plurality of members constituting an airframe of an aircraft, and an insulating sealant layer that is formed around the fastener member, the jig comprising:

• a sealant cup that overlays a sealant to be stored in a cavity on the fastener member;
• a cup holder that includes a guide for determining a position of the sealant cup with respect to the fastener member;
• and
• a dummy cup that determines a position of the cup holder with respect to the fastener member,
• wherein the cup holder is determined in position with respect to the fastener member by moving the guide along the dummy cup determined in position with respect to the fastener member, and
• the sealant cup is guided along the guide of the cup holder so as to overlay the sealant on the fastener member after removing the dummy cup from the cup holder determined in position with respect to the fastener member.