Sandwich Construction Fin Mounting

Abstract

Fin plug assemblies for mounting a removable watercraft fin are disclosed. In some embodiments the fin plug assemblies include a fin plug and a mounting insert, wherein the fin plug is configured to mount removable fins (e.g., surfboard fins) to a surface of a watercraft. In some embodiments, the mounting insert has a laminar or sandwich construction. Methods of manufacturing the fin plug assemblies and watercraft including the fin pug assemblies are also described.

1 . A fin plug assembly for removably mounting a removable watercraft fin on a water-facing surface of a watercraft, the fin plug assembly including:
 a fin plug comprising a fin housing configured to house and mount a mounting base of the watercraft fin;   a mounting insert having an insert body with operationally water-facing and inwardly facing surfaces, the mounting insert having a cavity formed in the water-facing surface that is shaped complementally to and configured to receive the fin housing;   the water-facing surface of the mounting insert being configured for co-operation with the water-facing surface of the watercraft;   the mounting insert body being configured for co-operation with and mounting within a cavity previously formed in the water-facing surface of the watercraft, the insert body shape being complemental to the cavity shape; and   the mounting insert having a laminar construction.   
     
     
         2 . The fin plug assembly of  claim 1  in which the mounting insert comprises an insert body with a laminated construction including a core made from a high density foam, a laminate on the inwardly facing surface constituted by a relatively more rigid laminate and a laminate on the water-facing surface constituted by a load dissipating laminate. 
     
     
         3 . The fin plug assembly of either of the preceding claims in which:
 the fin plug is constituted by a fin plug sub-assembly comprising a fin housing and a flange plate and the mounting insert is constituted by a mounting insert body comprising a number of laminated layers;   the fin housing having an externally cylindrical body, bulbous cylindrical ends and bulbous fin-securing grub screw posts, the external surfaces of which are part-circular;   the flange plate being configured for sandwiching between layers of the mounting insert body and having an aperture formed therein that is shaped complementally to accommodate the fin housing;   the aperture in the flange plate having a surrounding aperture wall that is cross-sectionally curved and shaped complementally to accommodate the cross-sectionally curved cylindrical portions of the fin housing to allow rotation of the fin housing within and relative to the flange plate.