USE/CARE OF HANDTOOLS & MEASURING TOOLS - OD1621 - LESSON 2/TASK 2
d. Maintenance and Repair of Chisels.
Chisels must be kept properly
ground and sharpened at all times in order to obtain good workmanship in the
Grinding is necessary when the cutting edge has been
badly nicked and the nicks cannot be removed by whetting on a coarse
oilstone, or when the bevel has become too short or rounded as a result of
frequent or careless whetting.
(1) Woodworkers's Chisels.
(a) Sharpening. A common oilstone having a coarse and fine grit
is used to sharpen a chisel which does not require grinding.
It is also
used to whet a chisel after grinding.
1 Clamp the oilstone in a vise, or make sure it is otherwise
firmly held so that it cannot move.
2 Cover the stone with light machine oil so that the fine
particles of steel which are ground off will float; this will prevent the
stone from clogging.
3 Hold the chisel in one hand with the bevel flat against the
coarse side of the stone.
For ordinary work, the bevel is sharpened at an angle
of 25 to 35. For fine cutting and paring, the angle
may be slightly less.
4 Use the fingers of your other hand to steady the chisel and
hold it down against the stone.
5 Using smooth even strokes, rub the chisel back and forth
parallel to the surface of the stone (figure 88 on the following page). The
entire surface of the stone should be used to avoid wearing a hollow in the
center of the stone. Do not rock the blade. The angle of the blade with
the stone must remain constant during the whetting process.