MARVEL 8 MARK III
MAINTENANCE
G-14
© MARVEL MFG. CO., INC. MANUAL 8SDN10871N (04/08)
RE-CALIBRATING THE BLADE
TENSIONER
Proper blade tension is essential for clean,
accurate cuts and long blade life. The blade
tensioner torque limiter was calibrated at the
factory to provide proper blade tension,
however, over time; it may be necessary to be
re-calibrated.
IMPORTANT: To accurately recalibrate, the
blade tensioner stop requires a blade tension
gauge. Refer to your blade manufacturer.
IMPORTANT: A new blade must be
installed before performing the following
steps. See Blade Changing Procedure.
The main electrical disconnect
switch must always be turned
to the "Off" position and
locked before adjusting,
servicing or cleaning the saw.
Failure to do so can result in
serious injury.
1.
Disconnect the saw's main electrical
disconnect switch and lock it in the "Off"
position.
2.
Open the upper and lower band wheel
covers and the upper blade guard.
3.
Position the upper blade guide so it is 16” to
18” (41 to 46 cm) above the saw table.
4.
Reduce the blade’s tension with the integral
air ratchet unit the blade can be hand
deflected approximately 1.5” (38 mm)
between the blade guides.
NOTE: If the blade is too loose, it will come off
of the band wheels and out of the blade guides.
5.
Clamp the blade tension gauge on the blade,
centered between the upper and lower blade
guides. Zero (0) the gauge.
6.
Slowly tension the blade, making sure it is
properly seated on the band wheels and in
the blade guides, until the tension gauge
indicates 30,000 lb/in
2
(2,200 kgs/cm
2
or 207
N/mm
2
).
This photo shows a Blade Tension gauge
mounted to the saw blade.
The UPPER BAND WHEEL TENSIONER has
an AIR RATCHET that is attached to a torque
limiter. The upper part of the TORQUE
LIMITER has a rotating member with catch
notches. After the blade is brought up to the
proper tension, set the tension adjusting screw
that moves the spring steel TORQUE LIMITER
CATCH so it just touches the catch notches in
the TORQUE LIMITER. See following photo.
WARNING
Tensioner
Air Ratchet
Cap of
Torque
Limiter
Minimal Gap between
Spring Steel Catch &
Limiter Cap
Tension
Adjusting Screw
Torque Limiter Catch-
Spring Steel Bar
