Wheel Inspection, Wheel Dressing, Wheel Replacement

Wheel Inspection

Before mounting a new grinding wheel, it must be inspected. Do not assume that a wheel is in sound condition just because it is new—often damage can occur in shipping, with age, or with exposure to moisture.

First, do a Visual Inspection. Look for any cracks, chips, nicks or dents in the surface of the wheel. If you see any of these, DO NOT use the wheel.

Second, do a Ring Test. This test will give you an indication of any internal damage that may not be obvious during a visual inspection.

To perform a Ring Test:

1.Make sure the wheel that you test is clean and dry; otherwise, you may get false results.

2.If size permits, balance the wheel with your finger in the hole. If this is not possible, hang the wheel in the air with a piece of cord or string looped through the hole in the center.

3.At the spots shown in Figure 3, gently tap the wheel with a light non-metallic device such as the handle of a screwdriver or a wooden mallet.

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Figure 3. Tapping locations when performing a

ring test.

H7758/H7759 8" & 10" Bench Grinders

4.An undamaged wheel will emit a clear metal- lic ring or “ping” sound in each of these spots. A damaged wheel will respond with a dull thud that has no clear tone.

5.If you determine from the ring test that the wheel is damaged, DO NOT use it!

Wheel Dressing

Depending on the type of grinding you do, the grinding wheel may require periodic dressing.

There are several different types of wheel dress- ing devices available on the market (see Page 16). Dressing restores the abrasive quality of the wheel surface and brings the wheel edge back to a square form.

Refer to the instructions that accompany your dressing accessory for complete details on how to properly dress a wheel.

Wheel Replacement

The wheel guard assembly must be removed in order to mount or dismount a grinding wheel.

To replace a grinding wheel:

1.UNPLUG THE GRINDER!

2.Remove the three Phillips head screws and nuts that go through the outer guard. Take off the outer guard and the rim guard.

3.Use a wrench on the nut that holds the wheel on the arbor. Hold the wheel from turning with your other hand. Note that the wheel on the left-hand side of the machine has left- handed threads, so the arbor nut on that side must be turned clockwise to loosen.

4.Remove the outer wheel flange and the paper disc. Pull the wheel free from the arbor. There will also be a paper disc and a wheel flange on the other side of the wheel.

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