(7) Using wrenches.
(a) Open end wrenches. It is important for a wrench to be a snug fit on
a nut or bolthead. If it is too loose, the wrench will slip and round the corners.
Make certain that the wrench fits squarely on the sides of the nut or bolthead (fig
13 and 14). Offset open-end wrenches make it possible to turn a nut or bolt that
is recessed and in limited quarters where there is little space to swing the
wrench. Turn the wrench over after each swing so that the opposite face is down
and the angle of the wrench opening is reversed (fig 14). Always place yourself so
that you can pull on the wrench to turn the work in the desired direction.
Do not push on a wrench; if the wrench slips or the bolt breaks loose
suddenly, you may skin your knuckles and be thrown off balance.
There are times, however, when the only way you can move the wrench is by pushing
it. In this case, do not wrap your fingers around it. Push it with the palm of
your hand and hold your hand open.
Fitting open end wrench.
Use of open end wrench.