adjoining teeth are staggered to the right, two to the
left, and so on. On the raker set blade, every third tooth
remains straight and the other two are set alternately.
On the wave (undulated) set blade, short sections of
teeth are bent in opposite directions.
The hacksaw is often used improperly. Although
it can be used with limited success by an inexperienced
person, a little thought and study given to its proper
use will result in faster and better work and less dulling
and breaking of blades.
Good work with a hacksaw depends not only upon
the proper use of the saw, but also upon the proper
selection of the blades for the work to be done. Figure
5-27 will help you select the proper blade to use when
sawing metal with a hacksaw. Coarse blades with
fewer teeth per inch cut faster and are less liable to
Figure 5-28.--Installing a hacksaw blade.
choke up with chips. However, finer blades with more
teeth per inch are necessary when thin sections are
being cut. The selection should be made so that, as
from the handle of the hacksaw (hand hacksaws cut on
each tooth starts its cut, the tooth ahead of it will still
the push stroke.) Tighten the wingnut so that the blade
is definitely under tension. This helps make straight
To make the cut, first install the blade in the
hacksaw frame (fig. 5-28) so that the teeth point away
Place the material to be cut in a vise. A minimum
of overhang will reduce vibration, give a better cut,
and lengthen the life of the blade. Have the layout line
outside of the vise jaw so that the line is visible while
When cutting, apply pressure on the forward
stroke, which is the cutting stroke, but not on the return
stroke. From 40 to 50 strokes per minute is the usual
speed. Long, slow, steady strokes are preferred.
For long cuts (fig. 5-29) rotate the blade in the
frame so that the length of the cut is not limited by the
depth of the frame. Hold the work with the layout line
close to the vise jaws, raising the work in the vise as
the sawing proceeds.
Figure 5-29.--Making a long cut near the edge of stock.
Figure 5-27.--Selecting the proper hacksaw blade.