General 90-170B M1, Руководство по установке и эксплуатации, Страница: 17 / 32

ADJUSTING BLADE TRACKING
Blade tracking means centering the blade on the wheels A .
Ideally, the blade should stay relatively centered on both
the upper and lower wheels.
Due to natural variations in castings, blade thickness or den-
sity and tire wear, absolute perfect centering alignment is
rarely attainable. A slight misalignment of the blade on the
wheels is inevitable and as long as it is kept to a minimum
(following the steps listed below) will not hinder the perform-
ance of the saw.
This misalignment is controlled and kept to a minimum by
adjusting the tilt angle of the upper wheel.
When adjusting blade tracking to center the blade on the wheels and assuming that perfect centering is not attain-
able, it is preferable to have the blade slightly off-center towards the front of the wheels rather than towards the rear
because the teeth on most bandsaw blades have alternating hook (one inner, one outer) – therefore if the blade is
centered too far back on the wheel (or if the blade tension is too tight), inner hooked teeth will dig into the wheel
tire and cause premature wear of the tire.
Nonetheless, to avoid having the blade come off of the wheels on it’s own during operation, the front edge of the
blades teeth should never be any closer than 3 mm (1/8”) from the front edge of the wheel
B .
BLADE CLEARANCE
Note: As previously stated, when performing blade installation, removal, tensioning or tracking, maximum clearance
between the blade and both upper and lower bearing assemblies is required to minimize friction, which would be
damaging to the blade. Refer back and follow the instructions for “blade clearance” before performing blade track-
ing adjustments.
A
B
3 mm - 1/8"
To adjust the blade tracking:
1. Open the upper wheel cover door then rotate the wheel
slowly forward by hand
A and check the position of the
blade on the wheel. The blade should remain as cen-
tered as possible on the wheel as it turns
B .
2. If the blade tracking must be adjusted, loosen the lock
nut
C on the tracking adjustment knobs D , then turn the
knobs:
- Clockwise if the blade moves toward the front of
the wheel. This tilts the top of the wheel to the back
and moves the blade toward the center.
- Counterclockwise if the blade moves toward the
back edge. This tilts the top of the wheel to the front
and moves the blade toward the center.
Note: Turn the tracking knobs in 1/2 turn increments, re-check
and adjust again as needed.
3. With the tracking set, re-tighten lock nuts C .
Note: The upper and lower wheels are factory set to allow for easy and
optimal blade tracking adjustments using the primary blade tracking
adjustment knobs, which adjusts the angle of tilt of the upper wheel. In
extremely rare cases, if acceptable blade tracking cannot be attained
through the primary adjustment it may eventually become necessary to
make minor adjustments to the angle of tilt of the lower wheel. The four
bolts
E
may be adjusted in or out to tilt the lower wheel up/down or
left/right as needed.
B
E
17
A
C
D