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7.3 Tracking the blade
Tracking position of the blade on the wheels
There are different opinions on the position that
the blade should be on the wheels. One group
of people recommends that with large blades
you should track the blade so that the teeth
hang just over the front edge of the rubber.
The second group recommends that all blades,
regardless of their size, should run in the center
of the wheel. The advantage of running the
large blades with the teeth not contacting the
rubber of the wheel is that they cannot damage
the tire. The disadvantage is that the wheel is
crowned and the blade is not tensioned in the
center of the band, which gives the blade a
tendency to wobble or flutter. The advantage
of running large blades on the center of the
wheels is that they are tensioned in the center
of the band and have fewer tendencies to
wobble and flutter. The disadvantage is that
blades with a large set on the teeth have a
tendency to damage the rubber of the tire.
This does not have a great effect on the
performance of the bandsaw, as all blades
are running on the center section of the tire,
which is not affected. We recommend that you
balance all blades on the center of the wheels
for optimum performance and a smoother cut.
1.
To track the blade, start rotating the wheels
by hand in the normal direction. As you do this,
watch the blade to determine where the blade
wants to track. If the blade is tracking too far
forward or backward, make small adjustments
with the tracking adjustment knob located at
the back of the bandsaw while still rotating the
wheel. Once the blade is tracking in the correct
position, fully tension the blade and re-track.
Lock the tracking adjustment handle.
Note.
Tensioning the blade is covered later in
the manual.
2.
Refit the plastic blanking block.
Note:
The blade must be fully tensioned for
final tracking.
Note:
Never track the blade with the saw
running.
Note.
There is a window on the side of the
bandsaw that
allows the blade on the upper flywheel to be
viewed. This will
assist you while you are tracking the blade.
7.4 Tensioning the blade
There are a lot of opinions on how to tension
a blade and if you should buy a blade tension
gauge. Before you purchase a blade tension
gauge, note the following points:
Most blade tension gauges are fitted to the
blade and measure the amount the blade
stretches when you tension it. Each blade
manufacturer uses a different type of steel with
different tensile strength. This means that each
type of steel has a different rate of stretch. For
example, if you buy a tension gauge from one
blade manufacturer, it is designed for use on
their blades, or range of blades, and will not
necessarily give you accurate readings in lbs/
square inch on another manufacturer’s blades
because their blades stretch at a different rate.
In reality, there is nothing quite as quick or as
accurate as experience. Your machine is fitted
with a blade tension indicator, which measures
the deflection of the tension spring on the upper
flywheel. We recommend that you use it only
as a general guide and use one of the following
tensioning procedures to tension the blade.
Method 1
Looking at the top wheel, place your finger at
the 9 o‘clock position. Move your finger down
15cm, and, using moderate pressure with
your thumb, press on the flat of the blade.
You should get 4 to 6 of deflection. Refit all
the guards and close the doors. Replace the
table insert and check that the blade moves
freely through the table insert. Check that all
wrenches and loose parts are removed from the
machine.
Plug the machine into the power. Turn the
machine on for a second and switch off. Watch
how the blade runs. If the blade tracks well,
then run the machine at full power. If the
Method 2
Tension the blade as described in method 1.
Close all the doors and ensure that all the
guards are fitted.
Start the band saw and look at the blade from
the front of the machine. Start to detension the
blade very slowly until the blade starts to flutter
(wobble from side to side). Then start to tension
the blade until the blade stops fluttering and is
running true. Increase the tension on the blade
by one complete turn on the tension handle.
You may find that each size and type of blade
will need more or less additional tension.
For example, a 1,5mm blade will need less
additional tension than a 19mm blade. Again,
experience is the key, and with a little practice
it will become second nature. The key to all
tensioning is to get the blade to cut straight
and true with the minimum amount of tension.
The less tension that you put on the blade, the
longer the blade and the machine will last.
Note.
The upper flywheel has a spring that is
used to keep a constant pressure on the blade
during use. As the blade cuts, heat is
generated, which causes the blade length
to expand. The spring compensates for the
change in length, and you must never bottom
out the spring while tensioning the blade.
Note.
If you are not using the bandsaw for
extended periods of time (overnight), remove
the tension on the blade. This will increase
the life of your blade and the machine. If
tension is left on the machine, flats or grooves
can be formed in the rubber of the wheels,
which will detract from the performance of the
machine and in extreme cases cause vibration.
Removing the
tension will greatly enhance the life of the
machine, bearings and tires. Label the machine
“detensioned.” On the label, mark the number
of turns that you detensioned; this way you will
know how many turns that you have to put back
on to have your blade correctly tensioned.
Removing the blade from the bandsaw
1. Disconnect the power to the bandsaw.
2. Remove the table split clamp that aligns the
two table halves.
3. Remove all the guards.
4. Remove the table insert.
5. Remove the tension on the upper flywheel.
6. Open the doors and remove the blade from
the wheels (use gloves and eye protection) and
gently slide the blade through the table slot.
Blade in column slot
Blade guard door
Plastic blanking block
Lock knob
Tracking knob
Blade tracking
window
Blade tension indicator
Quick action blade
tension lever (activated)
Blade tension
wheel
