Jet Tools JBG-6A Maintenance, Ring Test, Care of Grinding Wheel, Changing Wheels

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Maintenance

For safety, turn the switch to OFF and remove plug from the power source outlet before adjusting and maintaining the bench grinder. If the power cord is worn, cut or damaged in any way, have it replaced immediately.

Ring Test

Before replacing a grinding wheel, perform this simple test on the replacement wheel:

1.Loop a piece of string through the grinding wheel hole and suspend the wheel by holding up the string.

2.Tap the wheel with a piece of scrap wood or a wooden dowel.

A good wheel will "ring"; a defective wheel will "thud". Discard any wheel that does not "ring". An internal defect may not be apparent by visual inspection alone. The ring test may uncover an internal crack or void.

Care of Grinding Wheel

In normal use, grinding wheels may become cracked, grooved, rounded at the edges, chipped, out of true or loaded with foreign material.

Cracked wheels should be replaced IMMEDIATELY. While any of the other conditions can be remedied with a dressing tool (available at most hardware stores), new wheels sometimes require dressing to make them round.

Changing Wheels

If you must replace a wheel be sure to obtain one with a safe rated speed at least as high as the NO LOAD RPM marked on the grinder's nameplate. Refer to Table 2 to determine correct dimensions for the replacement wheel.

Model

Wheel

Maximum

Center

Diameter

Width

Hole

 

 

 

 

 

JBG-6A

6"

3/4"

1/2"

 

 

 

 

JBG-8A

8"

3/4"

5/8"

 

 

 

 

JBG-10A

10"

1"

1"

 

 

 

 

Table 2

Your bench grinder will accept most polishing and buffing wheels available at dealers and hardware stores.

The use of any other accessory is not recommended and may result in serious injury!

To change a wheel (refer to Figure 4):

1.Disconnect grinder from the power source.

2.Loosen the spark guard (A) and tool rest (B) (refer to the Adjustment section on page 11) and move the spark guard and tool rest away from the wheel.

3.Remove the guard cover using a Phillips or flathead screwdriver.

4.Stabilize the wheel by holding the opposite wheel firmly.

5.Unscrew the wheel nut (B) with a 1" wrench.

Note: Turn the locking nut on the right-hand wheel counterclockwise to loosen. Turn the locking nut on the left-hand wheel clockwise to loosen.

6.Remove the outer flange (C) and wheel (D).

7.Clean flanges. Check the flanges to make sure they are flat. Wheel flanges that are not flat will cause the wheel to wobble.

8.Put the inner flange, wheel (D), outer flange

(C) and nut (A) on the shaft. Tighten the nut. Do not over tighten. This may cause the wheel to crack.

9.Replace the guard cover. Adjust the spark guards and tool rests to a 1/16" clearance from the wheel (see Adjustments on page 11).

Figure 4

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Contents JBG Series Bench Grinders Warranty More InformationTable of Contents Page Page Introduction Specifications JBG-6AContents of the Shipping Container UnpackingAssembly Assembling the Spark Guard and Eye Shield Mounting BracketsInstalling the Spark Guard and Eye Shield Mounting Brackets Tool RestsEye Shields Mounting the GrinderElectrical Electrical RequirementsElectrical Connections Extension CordsAdjustments OperationMaintenance Ring TestCare of Grinding Wheel Changing WheelsWire Wheel Brushes CleaningLubrication Grinding WheelsTroubleshooting Problem Probable Cause RemedyParts and Assembly Parts ListTS-0680031 JBG6A-59A JBG8A-59AAssembly Drawing Wiring Diagram Replacement Parts