I recommend two separate sets of stones: one for narrow blades and
one for wide blades like plane blades. (A good beginning set of man-
made stones is 800X, 1200X, and 6000X or 8000X.) If you have only
one set of stones, use different surfaces for chisels and plane blades.
Waterstones are easy to reflatten. First, get a sheet of glass about
16-in. square and at least^1 ⁄ 4 in. thick. Round the corners and chamfer
the edges of the glass with silicon-carbide sandpaper. Place a wet sheet
of wet/dry silicon-carbide paper on the glass—it will stick by suction.
Use 80- or 100-grit paper if your stone is in poor condition, 150- or
180-grit paper for a slightly hollowed stone, and 320- to 600-grit
paper for slightly hollowed 6000X or 8000X manmade finishing
stones or natural finishing stones. While splashing on water, rub the
stone on the sandpaper in a circular motion until the entire surface
touches the paper. This is all you need to do for most stones.
For a perfect surface on a natural finishing stone or a 6000X or
8000X manmade finishing stone, after flattening, rub two finishing
stones together with plenty of water until the faces fit tightly and are
difficult to move. Don’t rub a natural stone against a manmade stone.
Stones that are badly worn can be rubbed on a concrete surface or on
a concrete block with plenty of water before going to the paper.
After flattening a stone, chamfer all the edges with a rough stone to
avoid chipping.
—TOSHIOODAT E,Woodbury, Conn.,
from a question by D. Christenson, Solebury, Pa.
.
SHARPENING & GRINDING