Good news about G10 is if you don't like the way they turned out, you can start all over.....don't need no stinkin belt sander....get some 120 grit sandpaper from the hardware store, and lightly rub on the scales.....too rough, go down to 220 grit....and so on til it feels just right for ya.
If the ones you have now are slippery and shiny, they could be 600 or even 1000 grit.