Sanding

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Sanding prepares the material to receive a finish.  The finish will only be as good as the surface preparation.

With any light colored wood or acrylic, you may want to cover the bushings with tape to keep metal sanding dust from the bushings from contaminating the blank.  Start with 9" x 11" sandpaper sheets and cut them into strips 11" long and 3/4" wide. 

There are several basic kinds of sandpaper.

Wood
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Wood is normally sanded dry.  A dust collector hose positioned just behind the blank will catch all the sanding dust and keep it out of your lungs!

Start with a 320 grit sandpaper.  You can start with a lower grit if necessary.

Sand upward from the starting grit; 150, 220, 320, 400, 600, 1200, 2000.   Do not skip any grits because the scratches from the previous grit will not be removed completely if you skip grits.

For each grit:

  1. Turn the lathe on and sand with a wiping motion across the blank.
  2.  Stop the lathe and sand lengthwise while turning the lathe slowly by hand.
  3. With the lathe off, wipe off any sanding dust with a paper towel.  Use denatured alcohol (DNA) for wood blanks, water for acrylic blanks.  Wipe the sandpaper too!
  4. Repeat with the next grit of sandpaper.


This sounds like a long process, but each grit of sand paper only takes 20 seconds.  It is important to sand the blank lengthwise with each grit to remove sanding rings around the blank.



Acrylics
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Acrylics should be wet sanded with wet and dry paper used with water.  Be sure to cover the ways of your lathe to keep water off the lathe.  Use a heavy rubber sheet commonly used to line tool box shelves.  Anything will do if it prevents water penetration and is solid.  Don't use cloth.

Sand upward from the starting grit; 150, 220, 320, 400, 600, 1200, 2000.   Do not skip any grits because the scratches from the previous grit will not be removed completely if you skip grits.

For each grit:

  1. Turn the lathe on about 400 RPM.  Put a drop or two of water on the sandpaper and sand with a wiping motion across the blank.
  2.  Stop the lathe and sand lengthwise while turning the lathe slowly by hand.
  3. With the lathe off, wipe off any sanding dust with a paper towel.  Wipe the sandpaper too!
  4. Repeat with the next grit of sandpaper.


This sounds like a long process, but each grit of sand paper only takes 20 seconds.  It is important to sand the blank lengthwise with each grit to remove sanding rings around the blank.