Skin fittings
This term embraces a variety of components
associated with necessary holes in the hull. For the main part, such fittings
take the form of metal or plastics pipes with flanges and backing plates.
Sometimes an inlet fitting will have a coarse integral strainer to keep out the
bigger particles of seaweed. A seacock itself may on occasions be termed a
‘skin fitting’, though in other contexts a distinction would be made between
the seacock and the skin fitting to which it is screwed. It is good practice to
reinforce the hull in the region of a skin fitting, usually with a backing pad.
The fitting must be well bedded, and bolts or other fastenings must be of a
material which will not corrode in sea water nor set up a galvanic action with
the material of the fitting itself.