Sanding Question
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Sanding Question
Yesterday, I finished sanding all the old finish off the back of the 00 I'm building. If you don't remember, I started spraying finish and after 3 or 4 coats my compressor broke down, then after getting it up and running I was a little panicked and sprayed coats too close together and got sags in the finish, and then I ran out of finish before building up enough coats. Finally, I sanded through the thin finish while trying to level sand the sags I had created. Bummer. So I decided to sand everything except the side back down and refinish. The sides look pretty good.
It took forever but I finally sanded through to bare wood removing even the z-poxy pore filler (not sure if that was necessary). The mahogany back looks nice but with a light at a low angle I can see scratches that are roughly 45 deg to the grain. While the finish/zpoxy was still on I sanded every which direction. But I sanded with the grain (220g) for quite a long time near the end.
So should I worry about these cross grain scratches? I really don't want to remove any more wood from the back but I will sand more if the cross grain scratches will show up under the finish. What do you think?
It took forever but I finally sanded through to bare wood removing even the z-poxy pore filler (not sure if that was necessary). The mahogany back looks nice but with a light at a low angle I can see scratches that are roughly 45 deg to the grain. While the finish/zpoxy was still on I sanded every which direction. But I sanded with the grain (220g) for quite a long time near the end.
So should I worry about these cross grain scratches? I really don't want to remove any more wood from the back but I will sand more if the cross grain scratches will show up under the finish. What do you think?
Slacker......
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Re: Sanding Question
Do they light up when wet with solvent like DA or naptha? If so they will show in the finish, if not you are good to go.
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Brian Howard
www.brianhowardguitars.com
Taylor authorized service
Custom finishing services
Brian howard's guitar building & repair blog
http://www.brianhowardguitars.com
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Re: Sanding Question
I have sanded the finish off of the top of my guitar after 10-12 coats of lacquer and it is a pretty tough job. My question is since it takes so much work to do this, why should I be concerned with sanding through the finish when I am leveling and wet sanding a finish? It just doesn't seem like that would ever happen.
Thanks
Thanks
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Re: Sanding Question
nehsgolfer, I'm guessing how difficult it is to sand through the finish is a function of how thick your finish is and how level the wood was before you started......and what grit sand paper you are using.
Slacker......
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Re: Sanding Question
As an alternative to sanding, how about stripping the finish with lacquer thinner? Needless to say, one would want a good vapor mask and no source of ignition nearby, but in my experience lacquer washes off fairly easily with lacquer thinner.
Don't believe everything you know.
Anything is possible if you don't know what you are talking about.
When things are bad, try not to make them any worse, because it is quite likely they are bad enough already. - French Foreign Legion
Anything is possible if you don't know what you are talking about.
When things are bad, try not to make them any worse, because it is quite likely they are bad enough already. - French Foreign Legion