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Does anyone know if an airbrush can give similar results as a french polished finish? I heard Mario did some guitars with an airbrush in the past. Are you out there Mario? Maybe you can chime in with your experience.

An airbrush will give you similar results to a sprayed finish, because it's still a tiny spray gun (albeit one that works on slightly different principles). They're also a bit on the tiny side for a guitar, good for controlling bursts and the like, but a bit painful for getting full coverage.

Before I did any guitar building I bought a Badger 150 airbrush and small reed valve compressor to spray rifle stocks with marine varnishes. I found that with the airbrush I could get superb, thin, even finishes in one continuous spraying session, but that it was almost dry as it hit the wood. I couldn't get it to produce a gloss finish without spraying too close and producing runs on the wood. This I didn't mind as I was after a sort of soft sheen rather than gloss finish.

Before I got into French polishing I thought I'd give the air brush a try on my first guitar and yes same result. I liked the look of the soft sheen finish and that is what I still aim for (perhaps with just a little more lustre) from my french polishing. However, if your after a deep gloss finish forget it, you'd be spraying from here to next year to get the depth of finish needed to buff out.

That said I'm going to be airbrushing varnish on my next lute to get that soft sheen finish again.

Colin

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I don't believe in anything, I simply make use of a set of reasonable working hypotheses.

The big difference in French polish and sprayed shellac finish is that when you spray you build up layers that slightly burn into each previous layer. When French polishing you build one continious amalgamated film. The result is entirely different look and film durability

I've been wondering about this because I only french polish my classicals and I usually apply the Bridge after the finish is applied. Now I would like to test my guitars in the "white" to do more fine tuning and I've always had trouble applying the finish around the Bridge and Fretboard. I already have a Paasche double action airbrush and I was thinking it might be good for those trouble areas. It's hard for me to see a difference in hand applying small layers of shellac vs spraying fine layers on. Does anyone have any pictures of the items they airbrushed shellac on? Did you have any problems with orange peel?

You will probably get just a little bit of orange peal. You would still have to rub-out in the areas around the bridge and fretboard if you sprayed these areas, to get it to blend wth the rest of the French polish. It is tuff not to get it on the bridge and FB and the alcohol can wick adhisive from masking tape if you mask them. It is still going to be difficult to get it to look as clean as it does when finished without the bridge and fretboard.

If we are talking steel String guitar here you can use the threaded tubes and nuts that Stewmac and Lmi sell to temp mount your bridge for testing, then take it off and finish it


MichaelP38637.5959143518