I took a few minutes tonight to go down to the shop and sand the banjo again. I have switched to 150 grit paper, but other than that, it is the same story. First I sand.
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Sand
Then I wet it down.
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Wet
The water brings out the curly figure in the wood.
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Curl
You can see why they call it "curly". The wood actually looks like curly, wavy hair. In fact, if you split a curly maple log, the surface will be wavy like that. But I have planed it flat, and I assure you that the curl in the photo is an illusion, and the wood is flat.