16
piece.
Use preventive maintenance.
Check the sawing force.
a. Tension the blade, spread the guide
arms and vise jaws. Raise the saw head.
Do not start the blade.
b. Close the saw head approach feed
control valve and press the saw head feed
control.
c. Open the saw head approach control
valve just enough to lower the saw head
slowly.
Tap the blade lightly at the guides, seating
the blade in the metering valve linkage.
Sawing force is adjusted by lengthening or
shortening the linkage that runs from the
metering valve to the carbide back-up
slipper. See drawing 010370A.
The metering valves close and the sawing
force/saw head stops applying force on the
saw blade.
To verify that the metering valve is working,
lift the linkage as shown in drawing
010370A. The frame should stop coming
down.
If more than .040" of travel is needed to stop
the frame, adjust the linkage as described in
section 8.
5. Metering valve linkage check.
If the sawing force check failed, linkage from
the back of the blade to the metering valves
may be worn or the blade guide blocks may
be pinching the blade.
Be certain the guides are flushed clean and
try forcing the tensioned blade in and out of
the blocks.
Under full tension the blade must only partly
return back up into the guide. If it hangs up,
sticks or slides too freely between the
blocks, go to step 6 for a blade guide check
before continuing here.
If the tensioned blade only partly returns
when pushed down out of the guides,
without hanging up, continue this check.
Linkage travel must not be less than .030"
and not more than .040".
More than .040" travel, the linkage too short,
will not control the metering valves and may
let saw teeth enter between the blocks, ruin-
ing the blade and the blocks.
Less than .030" travel, the linkage too long,
will hold the metering valves closed, hold the
saw head in suspension or come down only
slowly.
Check the linkage travel.
a) Fasten a dial indicator to the guide
arm with the contact point resting on the
back edge of the saw blade.
Set the dial to "0" and place a block of wood
under the blade next to the guide arm.
Use a piece of round stock in the blade tooth
gullet and bring the saw head down on the
block of wood.
When the saw head stops, read the dial indi-
cator. Check both guides.
b) If the blade is not hanging up in the
guides and blade travel at both guides is
.030" to .040", problems with the sawing
force check is not with linkage travel from
the back of the blade to the metering valves.
Go to step 7 for a metering valve check.
c) If linkage travel is more than .040" it is
too short to close the metering valves. The
probable cause is a blade track worn in the
backup slipper greater than .030". Go to
step 6, dismantle and inspect the guides and
backup slipper. If the backup slipper is not
worn adjust the linkage during the metering
valve check.
d) If blade travel is less than .030" the
linkage is too long to let the metering valves
control sawing force. The probable cause is
a backup slipper replacement and shims
