How do you protect ship rigging?

A Note on Cases ;

 I remember this from Scale Auto . A gentleman had put his model in the case .Some time later he noticed a sag and also a dulling of paint  , and loss of clarity on the windows of said model . Guess what ? he forgot something very important .Oil Based paints may " Gas - Out " for a month or two . Truly !

 So your case must breathe ! How do you acomplish this ? Well there are two ways . I have used them both with good luck . For ready made cases I drill a few holes under where the model is going to go .The holes drilled for hold downs help here .

  Now for a ship on a water base or natural wood ( even stained and varnished ) I will cut small slots about an inch apart into the plastic cover that will let air in and gasses out .  Even the cases of glass in Museums are vented in some manner .

A glass case is actually your friend, if only for limiting how much dust can collect.

Until you get the case, I heartily second Tanker's suggestion of a "blusher" brush.  Cheap at the drugstore or supermarket.  Nice and fluffy, too, so no danger of knocking things loos (if used carefully).  A teeny, tiny, miniscule quantity of Electronic component dust spray (think spray with one hand, and barely touch brush to spray for this; or spray on a paper plate and use a drybrush technique) can be your friend.

Too late now, but running all your lines trhoug a beeswax cake before installing them will help prevent future fraying.  Sometimes you can use a lit incense stick to gently (very gently, extremely gently, supremely gently) to "tease" the frays. 

Use extreme caution, it's extremely easy to burn a gap in the rigging.  So, heat/flame/ember is a last, last, last resort.

A case is significantly simpler.

I use my airbrush to clean rigging. I leave the bottle off (I use suction feed), and run the brush through the airbrush for several seconds making sure there is no thinner or paint in the airbrush.  Then I start blowing the rigging.  I use a small natural hair brush to gently touch any dust that doesn't come off with just the air.  I direct the air to the area I am brushing.

Hi ;

 Being as how she's already rigged it's not easy to keep her clean . Use a make-up Blush Brush and this should help . Usually  , I run the rigging thread through Bee's Wax Before using it on the ship .

 This seals the thread and prevents fuzzies . The Only way you'll keep it dust free though, is a case .