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What grit do you sand up to before finishing cocobolo or similar hardwoods? I went up to 320 and still see light sanding markes in low angle light reflection. I'm sealing with shellac, will there be a problem with adhesion if I sand up to higher grit?

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Jeremy Douglas

Jeremy bro I have been testing coco to see if I am sensitive to it because I want to build with it. So far so good.

I can get a smooth surface with no sanding marks at 220. I would caution you against going much high because you also, when finishing the guitar, want some mechanical adhesion to take place so the finish sticks well.

Jeremy,
I like to go to 220 grit, but am sure to finish up at that grit by having all of the movement in the direction of the grain. I never finish up using any type of orbital motion.

Once you've removed the previous grit's marks and have done it along the grain, you will have no trouble starting the finish process.

Regards,
Kevin Gallagher/Omega Guitars

I thought you meant, like, snorting it. That's probably quite a buzz, but like most cheap highs, not good in the long run.

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Howard Klepper
http://www.klepperguitars.com

When all else fails, clean the shop.

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That sounds more like a psychedelic crisis.

Thanks guys, I'll give it another go and see how it turns out... the sanding, not snorting.

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Jeremy Douglas

I find if you steel wook the guitar after you *think* you ahve the sanding scratches removed then hold it up at an angle to the light the remaining scratches will jump out like mad.

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Brock Poling
Columbus, Ohio
http://www.polingguitars.com

Brock, those are steel wook scratches....

Dan

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Dan
http://www.acme-archtops.com

Use a damp cloth... wet the wood and let it dry. Do a final sanding and all the scratches should be gone.

Wet sanding raises the grain and will break up all the sanding scratches.

I wonder if it has something to do with the density of the wood and/or the smoothness of the surface. I can't see scratches on mahogany when sanded to 220 but can easily see them on the cocobolo. I know if you sanded something with a smooth surface like a finished guitar with 320 grit you'd see the scratches. The sanding marks will be there but whether you can see them or not is another story. Maybe it's my technique, I'll try again tomorrow, but I sanded by hand with the grain and even tried sanding very gently and yes the marks are from the 320 and not a lower grit.

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Jeremy Douglas