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.
Sand
Then I wet it down.
Wet
The water brings out the curly figure in the wood.
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.