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checking adjustments and by exercising care in opera'
tion, and you will be rewarded by increased life and
service from your blade.
Excessive tension greatly shortens the life of the
blade.
Failure to bring the upper guide assembly down
close to the work allows distortion of the blade which
encourages breakage.
Excessive feed pressure causes the blade to ride
hard on the thrust roller, the friction hardens the
blade edge which causes cracking and breakage. A
dull blade, or one that has been improperly set or
sharpened will require much greater feed pressures
than a good, sharp, properly set blade. To keep the
blade in good cutting condition it should be sharp-
ened after every 4 to 6 hours of actual cutting.
If the guides are set too close to the blade, rubbing
constantlJy', or causing blade defection, the blade life
and service are definitely shortened.
Both the guides and the blade will be damaged if
the guides touch the teeth rather than the smooth
sides of the blade when lateral thrust may be applied
during the cutting of irregular shapes.
A poor weld where the blade ends are joined, or a
weld that is improperly
dressed down, leaving a
bump, is often a cause of short blade life.
If the blade is allowed to rust, either on the tool or
in storage, pitting caused by rust may be severe
enough to cause breakage. Oil all blades before stor-.
ing-tlnipe oil off before installing on Band Saw.
Finally one of the most common causes of blade
difficulty is the practice of cutting too sharp a radius
or of turning the work piece too fast when cutting a
radius thus binding or twisting the blade. Following
is a table showing the minimum radius which should
be cut with various width blades.
Blade Width
Inches
3 / t 6
t / 4
3/8
Minimum Radius
Inches
t / 2
I
3
FIGURE '
It is generally considered a good policy to work at
least /a inch over the specified minimum radius.
When storing blades, they may be folded simply
and conveniently in the following manner:
Hold the blade in front of you, teeth pointing away,
so that you can look through the circle formed by the
blade. Grasp the blade with the left hand so that the
thumb is on the smooth edge of the blade toward
your body and the fingers are on the blade teeth.
Place the right hand at a spot directly across the circle
so that the thumb is away from the body on the saw
teeth while the fingers are on the smooth edge toward
the body. The hands should now be on opposite sides
of the circle and in exactly opposite positions-1hs
palm of the left hand and the back of the right hand
toward your body. Without letting go of the blade,
twist each wrist until the palm of the right hand and
the back of the left hand is toward the body. As the
hands are moved slowly to within 6 to 8 inches of
each other during thiS twisting motion, the blade will
fall into a folded pattern of 3 small circles as shown
in the parts illustration. ,A small loop of string or 6ne
wire applied at two opposite points on the small
circles will hold the blade in this shape till released
for reinstallation on the saw.
OPERATION:
Hold the work piece 6rmly against the table surface
during cutting operations. If the piece is allowed to
tilt or otherwise raise from the table, the angle of the
cut will not be square.
To simplify the cutting of complex 6gures, it is
advisable to rough out the general shape before finish-
ing the cut on the planned line, If possible, when you
come to a sharp curve, cut it with a series of tangent
cuts rather than in one operation. It is often more
practical to turn and cut out through waste stock
rather than to pull a partially completed cut back off
the blade, thus running a risk of catching the blade
and pulling it off the wheel.
If you keep your mind slightly ahead of the blade,
thus anticipating curves and changes in position of the
work piece, you will find it much easier to follow the
planned line. Sharp turns often may be cut much
more e'asily after drilling out the area near the turn
before starting the sawing operation. Corners are cut
guite easily by first cutting around the corner in a
comfortable radius and then returning to saw the
corner from each side.
Narrow slots can be worlced out by making repeat
cuts to the end of the slots.
Do not force the work against the blade in excess
to the cutting capacity of the blade as this will make
the following of a pattern extremely difiicult.
A few practice cuts should enable one to get the
feel of band sawing.
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