12

the wheel shoulder. Put a 6-inch length of paper between the blade and the wheel as shown in figure

11. The paper should not be cut as it passes be- tween the wheel shoulder and the blade.

9.Turn the single hex adjustment screw a small amount. Repeat the insertion of the paper between the wheel shoulder and the blade until the paper is cut in two pieces.

NOTE: You may have to repeat the check with the paper several times before the blade and the shoulder cuts the paper into two pieces. Do not hurry the ad- justment. Patience and accuracy here will pay off with better, more accurate, quieter cutting and much longer machine and blade life.

10.When the paper is cut, turn the hex adjustment screw slightly in the counterclockwise direction. This assures that the blade is not touching the shoulder of the wheel.

11.Shut off the saw.

12.Hold the hex adjustment screws with a wrench and tighten the center locking screws. Make sure the hex adjustment screws do not move while tightening the center screws.

13.Install the two blade guide bearing brackets. Posi- tion the guides so the bearings just touch the blade.

14.Install the left blade guard.

15.Close the saw head cover. Tighten all four knobs.

Motor "ON"

Upper Wheel

Rotating

Put Strip Between Wheel and Blade

Figure 11: Checking blade-to-wheel clearance using paper strips

Blade Guide Bearing

Adjustment

Proper adjustment of the blade guide bearings is critical to efficient operation of the cut-off saw. The blade guide bearings are adjusted at the Factory. They

should rarely require adjustment. When adjustment is required, adjust immediately. Failure to maintain proper blade adjustment may cause serious blade damage or inaccurate cuts.

It is always better to try a new blade when cutting performance is poor. If performance remains poor af- ter changing the blade, make the necessary adjust- ments.

If a new blade does not correct the problem, check the blade guides for proper spacing. For most effi- cient operation and maximum accuracy, provide 0.001 inch clearance between the blade and the guide bear- ings. The bearings will still turn freely with this clear- ance. If the clearance is incorrect, the blade may track off the drive wheel.

CAUTION: CHECK THE BLADE TO MAKE SURE THE WELDED SECTION IS THE SAME THICKNESS AS THE REST OF THE BLADE. IF THE BLADE IS THICKERAT THE WELD, THE GUIDE BEARINGS MAY BE DAMAGED.

If required, adjust the guide bearings as follows:

1.The inner guide bearing is mounted on a concen- tric bushing and can not be adjusted.

2.The outer guide bearing (closest to the operator) is mounted on an eccentric bushing and can be ad- justed.

3.Hold the bushing with a 3/4-inch wrench and loosen

Guide Bracket

Eccentric

Bushing

Locking

Screw

Blade

Outer Roller

(Blade Guide Roller)

Figure 12: Adjustment of guide bearings

INCORRECT

CORRECT

Outer

Inner

 

Roller

Roller

 

Blade

 

Locking

 

 

 

 

Screw

Figure 13: Blade -to-bearing orientation

Page 12
Image 12
Jet Tools J-7020, J-7040 Blade Guide Bearing Adjustment, Checking blade-to-wheel clearance using paper strips