Roger - right or wrong I used my touch up to cover spots in the powder coat where I had sanded or filed and exposed the 4130. In all rights, I should have put down some primer first but all of the areas are easy to access and where I will see them when flying or during a conditional inspection. If rust appears I'll fix it properly then. BTW - after 1.5 years it started to get a little too thick and lacquer thinned worked well to bring it back to life. It only took a small amount.