saws are much the same with regard to maintenance,
operation, and adjustment.
A rule of thumb used by many Seabees is that the
width of the blade should be one-eighth the minimum
radius to be cut. Therefore, if the piece on hand has a
4-inch radius, the operator should select a 1/2-inch
blade. Dont construe this to mean that the minimum
radius that can be cut is eight times the width of the
blade; rather, the ratio indicates the practical limit for
high-speed band saw work.
Blades, or bands, for band saws are designated by
points (tooth points per inch), thickness (gauge), and
width. The required length of a blade is found by
adding the circumference of one wheel to twice the
distance between the wheel centers. Length can vary
within a limit of twice the tension adjustment range.
Band saw teeth are shaped like the teeth in a hand
ripsaw blade, which means that their fronts are filed at
90° to the line of the saw. Reconditioning procedures
are the same as those for a hand ripsaw, except that
very narrow band saws with very small teeth must
usually be set and sharpened by special machines.
Observe the following safety precautions when
operating a band saw:
Keep your fingers away from the moving
Keep the table clear of stock and scraps so your
work will not catch as you push it along.
Keep the upper guide just above the work, not
Dont use cracked blades. If a blade develops
a click as it passes through the work, the
operator should shut off the power because the
click is a danger signal that the blade is cracked
and may be ready to break. After the saw blade
has stopped moving, it should be replaced with
one in proper condition.
If the saw blade breaks, the operator should
shut off the power immediately and not attempt
to remove any part of the saw blade until the
machine is completely stopped.
If the work binds or pinches on the blade, the
operator should never attempt to back the work
away from the blade while the saw is in motion
since this may break the blade. The operator
should always see that the blade is working
freely through the cut.
A band saw should not be operated in a
location where the temperature is below 45°F.
The blade may break from the coldness.
Using a small saw blade for large work or
forcing a wide saw on a small radius is bad
practice. The saw blade should, in all cases, be
as wide as the nature of the work will permit.
Band saws should not be stopped by thrusting a
piece of wood against the cutting edge or side
of the band saw blade immediately after the
power has been shut off; doing so may cause
the blade to break.
Band saws with
36-inch-wheel diameters and larger should
have a hand or foot brake.
Particular care should be taken when
sharpening or brazing a band saw blade to
ensure the blade is not overheated and the
brazed joints are thoroughly united and
finished to the same thickness as the rest of the
blade. It is recommended that all band saw
blades be butt welded where possible; this
method is much superior to the old style of
Figure 3-4 shows a drill press. (The numbers in
the figure correspond to those in the following text.)
The drill press is an electrically operated power
machine that was originally designed as a
metal-working tool; as such, its use would be limited
in the average woodworking shop. However,
accessories, such as a router bit or shaper heads, jigs,
and special techniques, now make it a versatile
woodworking tool as well.
The motor (10) is mounted to a bracket at the rear
of the head assembly (1) and designed to permit
V-belt changing for desired spindle speed without
removing the motor from its mounting bracket. Four
spindle speeds are obtained by locating the V-belt on
any one of the four steps of the spindle-driven and
motor-driven pulleys. The belt tensioning rod (16)
keeps proper tension on the belt so it doesnt slip.
The controls of all drill presses are similar. The
terms right and left are relative to the operators
position standing in front of and facing the drill press.
Forward applies to movement toward the operator.
Rearward applies to movement away from the