Scoring Blade Belt Tensioning; Arbor & Arbor Bearing Removal; Splitter Alignment; Blade Raising Mechanism Adjustment - Powermatic 74A Instruction Manual & Parts List

FIGURE 9

SCORING BLADE BELT TENSIONING

The scoring blade belt is tensioned by the weight of
the motor. If the belt should lose its tension, check
the scoring motor pivot screws for binding. See Fig-
ure 9.
ARBOR AND ARBOR BEARING REMOVAL
To remove the saw arbor, remove the table top. Re-
move the lock nut, pulley and key. Use a wrench on
the end of the arbor to hold it while loosening the nut.
Loosen the setscrew in the saw raising arm and the
arbor; bearings and spacer will then slide out of the
arm housing, Figure 10.
FIGURE 10
BLADE RAISING MECHANISM
ADJUSTMENT
If binding occurs, clean off all sawdust and pitch build-
up and lubricate with a good non-hardening grease
such as Fisk Company Lubriplate. If binding contin-
ues, check the fit-up of the worm and worm gear seg-
ment. The worm must be centered with the worm
gear segment. It if is not centered, loosen the saw
raising arm setscrews and move the arm as required,
Figure 11, and re-lock.
If saw arm has been relocated, the table may have to
be realigned so as to provide clearance between the
saw blade and the table insert slot, and the splitter
will have to be realigned.
NOTE: The saw arm setscrew must be tight to avoid
the possibility of movement which could cause the
blade to hit the insert.
FIGURE 11

SPLITTER ALIGNMENT

One of the most critical adjustments to help avoid kick-
backs is the splitter alignment. It should be checked
and readjusted if necessary after each blade change.
To align the splitter to the blade, use a combination
square against the side of the raised up miter gauge
bar and slide the scale against the top of the tooth as
shown in Figure 12.
Check the splitter for parallelism to the miter slot and
readjust if required. Check for clearance.
Move the miter gauge to the opposite side of the blade
and using the combination square, slide the scale
against the top of the tooth. Check for clearance.
Clearance should be approximately equal on both sides
of the blade.
The insert will have to be removed to get at the adjust-
ment jack screw mounted in the center trunnion.
FIGURE 12

SCORING BLADE KERF ADJUSTMENT

Make a cut part way through a board with the main
blade (scoring blade down). Using a feeler gauge,
check the width of the kerf of the main blade. Raise
the scoring blade and make a cut part way through a
board with it. Check its kerf width using a feeler gauge
also.
9