rp. Even then the lower arris (corner) is likely to be splintered
off. This can be prevented by clamping the work down tight with a
handscrew to a perfectly smooth cutting board. It is often advisable
however, to set the piece upright in the vise and pare off thin
shavings horizontally, Fig. 74. In rounding a corner, both this and
perpendicular chiseling are common methods. In both cases care should
be taken to cut from the side toward the end and not into the grain,
lest the piece split, Fig. 75. In horizontal end paring, Fig. 74,
in order to prevent splintering, it is well to trim down the arrises
diagonally to the line and then to reduce the rest of the end surface.

In all hand chiseling, it is a wise precaution not to try to cut out
much material at each stroke but to work back gradually to the line.

[Illustration: Fig. 76. Mallet Chiseling. The Piece is Clamped Down on
the Bench With the Bench Hook.]

A typical form of mallet chiseling is the digging of a mortise, Fig.
76. (See also p. 56.) The chisel is held perpendicular in the left
hand, while the right hand drives blows with the mallet. The hammer
should never be used. (See mallet, p. 96.) By rocking the chisel and
at the same time giving it a twisting motion while the edge is kept
on the wood, the edge can be stepped to the exact place desired. Care
should be taken to work back to the lines gradually, to cut only part
way thru from each side (in the case of a thru mortise-and-tenon), and
to keep the cut faces perpendicular to the surfaces.

In sharpening a chisel it is of first importance that the back be
kept perfectly flat. The bevel is first ground on the grindstone to
an angle of about 20 deg. and great care should be taken to keep the edge
straight and at right angles to the sides of the blade.

[Illustration: Fig. 77. Whetting a Plane-Bit.]

After grinding it is necessary to whet the chisel and other edged
tools. (See also under oilstones, p. 121.) First see that there is
plenty of oil on the stone. If an iron box be used, Fig. 77, the oil
is obtained simply by turning the stone over, for it rests on a pad of
felt which is kept wet with kerosene.

Place the beveled edge flat on the stone, feeling to see if it does
lie flat, then tip up the chisel and rub it at an angle slightly more
obtuse than that which it was ground, Fig. 78. The more nearly the
chisel can be whetted at the angle at which it was ground the better.
In rubbing, use as much of t