LBrandt wrote: ↑
Thu Oct 11, 2018 7:47 pm
I’ve never owned a guitar with a nitrocellulose finish, but I’m considering a guitar that has a nitro finish, and I have a few questions about such a finish.
I’ve read that a nitro finish never “cures”, and that it’s easily marred. Now, I’m not one that worries about nicks, etc., as I know that a guitar is to be played and not put on display. One or two of my polyurethane finish guitars has the occasional nick, and that’s ok.
My concern is that I’m just wondering about the durability of a nitrocellulose finish, so I’m asking those of you who have guitars with a nitro finish to advise me on the subject.
Basically, nitro is a lacquer.The nitrocellulose, like shellac, is dissolved in a solvent and sprayed onto the surface. As the solvent dissolves, it leaves behind the finish. When people are saying nitro does not cure, what they are talking about is that it takes a long time for all of the solvent to evaporate. As it does evaporate, it will tend to shrink. This is why most companies that supply those "cling on" scratch pads advise against applying them to new nitro finishes. They'll trap the escaping solvent gases and cause checking.
I just received my first guitar with a nitro finish about a year ago and I can tell you it is an easy to scratch finish. Modern nitro is incredibly soft. It's prone to scratches, checking (from weather exposure), and cracks. However, the plus side is that because it is a lacquer, it can be redissolved in its own solvent, which in turn makes it easy to repair. (Or so I've been told.)
EDIT: Alan answered this way better than I did.