Paint chipping off of wire

The only suggestion I can think of is put it on last, and don't bump it!

It might - might - help to give the wire a coat of metal primer.  (In the case of a degausing cable, you might be able to airbrush a thin line of primer along the length of the wire.  Depending on the brand of primer, it probably wouldn't craze the plastic if sprayed carefully.)

The following probably isn't relevant to this particular problem, but it's a trick I've found useful in other applications involving wire.  I picked it up from one of the model railroad magazines.  (Those publications contain lots of information that's valuable for other kinds of modeling - including ships.)  Pactra makes a line of acrylic paint that's intended specifically to be airbrushed on slot car bodies.  Those things are made out of some rather flexible clear plastic; the modeler sprays the paint on the inside of the molding.  The guy who wrote the article in the railroad magazine had discovered that, because this stuff is designed to be flexible, it works beautifully on wire parts (such as grab irons, hand rails, etc.).  A friend of mine asked me for help on an HO caboose kit, and I tried the Pactra stuff (I don't remember the specific brand name, but our local hobby and craft store carries it) on the bright yellow handrails and grab irons at both ends of the car.  I put it on with a brush, straight from the bottle, and it worked like a charm.  The paint stuck with no primer, dried quick, and shows no tendency to flake or rub off.

The drawbacks are that it only comes in a relatively narrow range of colors, and they're all glossy.  And it has a rather odd, syrupy consistency; I don't imagine it would respond well to any sort of thinning (though I haven't tried that).  I have no idea what would happen if one were to apply a coat of flat finish over this stuff; I don't see why that shouldn't work (though I suppose the flat finish might flake off if the wire flexed).  I haven't run into a ship modeling application for this paint yet, but I'm on the lookout for one.  Seems like the black paint could come in especially handy.

I have been doing brass HO models for decades.  Same problem ALL the time, paint rubbing from wire.  Floquil primer brushed on, let set 48 hours minimum, Floquil color.  Don't touch for another 48 and you have a chance.

I think the type of paint jtilley is referring to is that designed for polycarbonate car bodies such as the big R/C models.  If so, I too can vouch for it's ability to hold on even when the underlying plastic is bent through 180 degrees - truly remarkable.

Tamiya makes a large range also but they too are mainly in bright (read garish) colours, as you would expect on racing car bodies.  They are designed to be applied to the inside of the car bodies (so they have to be applied in reverse logic which takes a bit of getting used to!).  Whether suitable greys can be mixed from the black and white and then matt-coated I've never tried.

Michael 

Apply a chemical blackening agent to wire before painting. It helps paint adhesion and chipped areas will not shine and call attention to themselves.  Note- the model railroad type blackener I tried was susceptible to rubbing and chipping.  Blackeners made for professional jewelers are the most reliable.  They are also toxic, so follow the directions.   HTH

Dave