Assuming you are asking about spinner blades, thinner coatings are best heavier high build coatings make some blade shapes inoperable.
I like clear lacquer on blades. Easy to control thickness. I have a couple gallons left over from car painting days and it is still available just a bit harder to find. Many auto parts stores carry a few spray cans just be sure you get a solvent based product. Not water based.
I did try DN Lure coat
http://www.dicknite.com/s81.htm and it is thin and may work for blades. I used it to seal a bunch of Vibrating blade baits last fall and did not have chipping issues. it is a simple dip coating drip dry, wipe off drip with a toothpick and let cure. I let it hang in sunlight for a couple of days. Product has a limited shelf life and critical storage.
Epoxys, Envirotex lite may thin down enough, D2T will probably be too thick. Both are very durable when mixed correctly and forgiveness of mixture goes to D2T. I have tried some rod finishing epoxey but was not overly happy. Both are available at craft stores and some hardware stores.
many guys over on TU are swearing by DST Concrete sealer, low build and very durable once cured and it is slow to cure. I have not tried it on blades but the few jigs and dozens of crank baits I top coated with it have done well. Smallest QTY available is gallon but not overly expensive considering a gallon will last a lifetime. Locally, it is available at mendards. Store in a cool dark place tightly sealed and it should last forever.