How to get Naked

[mmukav]

What do you use to remove a finish in preparation for applying a new finish.? If you use solvents won't they soak into the wood and destroy the tone? If you use sanding, won't you run the risk of removing wood? I've read articles about violin refinishing where they scrape the old finish off, with a razor blade or scraper.

[sunburst]

How do you remove what finish?
Some finishes can be removed with solvents and others can't. Solvents will evaporate out of the wood and wont have a lasting effect. You can ruin some plastic bindings with solvents. Some finishes will scrape off fairly easily and others feel like steel. If you sand down to the wood carefully and stop, you wont remove much wood.
Basically, you have to know what finish you're dealing with andmake a decision about the best way to remove it.

[mmukav]

How do you remove each type? Nitro, lacquer, varnish.

[grsnovi]

You seem to be asking a lot of questions lately that lead me to believe you are still considering refinishing your own mandolin.

The one with the cracked fretboard.

You would do well to go buy a couple of books and/or videos from someplace like Stew-Mac as I think it is highly unlikely that the collective knowledge of the folks on this board will be able to simply talk you through doing something like this the first time.

I certainly would not be stripping down a relatively new Gibson as my first "project".

[sunburst]

Well, nitro means nitrocellulose lacquer. It will dissolve in (and can be removed with) lacquer thinner, acetone, comercial paint strippers, etc. It your bindings are celluloid plastic, they'll be removed too. Lacquer (nitro) isn't too hard to scrape, and is a little tough to sand, but it can be done.

Varnish can mean shellac, shellac based spirit varnish, oil varnishes with phenolic resins, alkyd resins, polyurathane resins, or natural resins, and any number of modern catalized varnishes, etc.

Shellac and spirit varnishes can be removed with alcohol, but it ain't easy. They do scrape easily and that would be the reason for scraping the varnish off of a violin.
Oil varnishes do not respond well to solvents, or sandpaper, so scraping is probably the best way. Also the reason for scraping violins. Those that don't have spirit varnish have oil varnish.

Modern catalized and epoxy varnishes don't respond well to anything, so a lot of scraping or sanding is about the only way.

[sunburst]

You would do well to go buy a couple of books and/or videos from someplace like Stew-Mac as I think it is highly unlikely that the collective knowledge of the folks on this board will be able to simply talk you through doing something like this the first time.
I might suggest the book:
Understanding Wood Finishes

I can't remember the author or publisher, but it's where some of the info in my other post came from.

[mmukav]

I ask these questions mostly out of curiosity, and boredom since at this time of year we're all going a little stir crazy until the weather moderates and we can get out in the yard. I love the fact that there's a wide range of knowledgable people who read and respond at this site. And don't worry, I won't do anything crazy with my A9, right now it's just sitting here waiting for authorization from Gibson to have it looked at. The reason I asked about the finish removal is that a couple years ago I had an old fiddle I repaired and refinished and a local luthier said I ruined it by removing the old finish with solvent. I think it sounds great, and he didn't argue with me but claimed it would have sounded much better without if I had not used the solvent. I just wanted to see what people on this site thought of the subject.