After having spent many hours and in some cases years to create a work of art, you want to protect your ship model the best you can.
Protection starts at the build stage by avoiding chemical deterioration. All metals tend to oxidize to some degree. Typical metals found in a ship model built these days are Britannia (pewter type alloy), brass, copper, steel, stainless steel, tin alloy and aluminum. Prior to assembly, you should wash the metal parts with a mild soap and water, dry thoroughly, assemble then brush them with a lacquer clear coat. The lacquer clear coat can be found in your wife's medicine cabinet labeled clear nail polish.
To avoid biological deterioration, protect wooden parts with paint, clear varnish, oil or stain. Prepare the wood for staining or painting by sanding and then cleaning the wood. Sanding opens up the wood's grain so the wood stain or paint can better penetrate the wood's surface. When sanding is complete, remove all of the dust created by sanding. It's best to do this with something called a tack cloth-a pad made from treated loose weave fabric. Tack cloth catches almost every molecule of wood dust. When staining remove excess stain, wipe away stain which is sitting on the wood surface then rub the pigment into the wood with a soft cloth using a circular motion. Wipe one last time in the direction of the wood grain; This helps promote uniformity. To deepen the stain color, repeat the process until desired results are achieved. Lastly, choose a polyurethane topcoat with the desired sheen. Oil finishes such as Tung Oil harden when exposed to air. Tung oil soaks into the wood fibers before it begins to harden, thus forming a protective finish that moves with the wood.
Rigging lines can be preserved by coating them in bees wax. The bees wax not only will prevent fraying but act as a barrier to moisture so that the lines don't continually stretch and loosen depending on the amount of humidity in the room. If using the cake method, draw the line through the slots in the container, two to three times, giving the line a small turn with each pass. Now, you could now run the line across the surface of a 60 watt light bulb to melt the wax into the line.
To keep sail cloth material from deteriorating, visit your wife's medicine cabinet again and borrow her hair spray. A light spray will not only protect the sail but will hold the sail in a billowing form if that is how you would like it displayed. The biggest enemy of the sail cloth is the sun.
Where you display the model in your house is important. The model should not be displayed in direct sunlight or near a heat source. If you need to augment the lighting, use low voltage (low temperature) LED's.
The accumulation of dust, oil and dirt can be avoided by encasing your ship model. A solid case …