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Just curious how much do you guys allow for final sanding when you thickness sand your tops/sides/backs?

I don't know you, and this is crazy, but heres my number; Sand .005-.010 maybe?

But seriously, it's not something I think about because my target thickness always accounts for (hopefully) the same amount of final sanding.

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Pat

What happens when sanding something like figured Maple? I've read (from a highly respected figure) that some of the grit can embed into the flame.

Maybe not the best process but here's what I do. I sand till my deflection test jig gives me the right answer, for example, 0.25" deflection over 18" with 5 lb bar in the middle of a joined D-size back. It will get a bit thinner when I clean up the rosette but I try to take of minimal additional material.

Guess that didn't really answer the question but for backs and sides I shoot for no more than .010" over.

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Steve Smith
"Music is what feelings sound like"

usually about 0.010".

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-Marcus
http://www.bailieguitars.com
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Hey Steve - How do you know what is the "right answer"? This is getting into the Gore/Gillet science stuff. I have the books..need to read over this part (I typically gloss over all the equations, takes the fun out of building for me).

Hi Gil, I have no idea if I have the right answer but here's the path I've traveled to get get where I am. I started by trying to do Chladni testing after reading several years worth of Al Carruth's excellent posts. Unfortunately I didn't have a lot of success so I decided to try deflection testing after reading a really detailed thread on the subject either here or at the MIMF. I worked my way through David Hurd's "Left Brain Lutherie" book, spoke with him several times and also corresponded for a while. I based my original starting numbers on deflection test calculations I did based on David's book and, to be honest, on the numbers that were published by a luthier (I don't remember who) whom I felt really had his act together.

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Steve Smith
"Music is what feelings sound like"