how do you clear coat something?

how to apply?

caitlinsdad is totally right, but just to add two things- when clearcoating a synthetic(plastic,etc) or metal, make sure to clean with a solvent that won't damage it, to avoid fisheyes.(separations where the clearcoat will bead instead of sticking) This can be caused by contaminants like grease/soap, but also by the binders put off by curing plastic.
most plastics are undamaged by denatured or isopropyl alcohol.
with wood that has been previously finished, look out for waxes/polishes. they too will impair a nice coat.
for trouble surfaces, a clear adhesion promoter may be most effecacious!(auto paint store, probably a purple can with a pic of a dog on it.)
caitlinsdad8 years ago
Depends on what you want to coat. For wood, you usually just brush on clear finishes with a good quality brush or use a foam applicator or synthetic material pad. You can also spray with a HVLP finish sprayer. There are your polyurethanes that come in gloss, satin, and semi-gloss, natural finish. And you have your lacquers, shellacs, and varnishes. There are finer techniques for each. For other smooth surfaces like plastic or metal, spray application is usually the best. You have your clear coat enamels in various gloss levels in handy spray cans. Apply in thin even coats, and build up your finish. Work quickly enough so that you are covering the area by joining back to a wet edge of the previously painted area. For craft projects, they sell 2-part resin kits to make a deep clear coat. You can do dry or wet sanding between coats with progressively finer sandpapers depending on what it is but be sure to remove any sanding dust with a tack rag. You will get a good finish if you avoid puddles and brush marks and work with each layer when it is completely dry. Good luck.