It's been a few times now I've put a clear coat or something over an existing finish, and had it 'bubble up' like paint remover!! Made a mess of a guitar once, cost me $115 to get it fixed... :( taught me a lesson...
Another time I put a gray primer over a piece of aluminum, and then sprayed it with a faux 'hammered metal' finish, and it all bubbled up...
Other then buying all the products I use from one company and tossing out my paint cabinet, is there some way to tell?
thanks