Bench Grinder


Table of Contents

About this Machine

This machine has two grinding wheels. See the diagram below,

Machine Safety

How to Get Help

Ask a Manager if you have any questions.

Using this Machine

These sections describe the standard usage and common pitfalls.

Setup

You can use this machine for woodworking, metal grinding, buffing, tool sharpening, metal cutting, shaping, etc. Before you start operation check the following,

  1. Before each use, check all nuts, bolts, and screws for tightness; Vibration during mixing may cause these to loosen.
  2. Avoid accidental starting. Be sure the Power Switch is off before plugging in.
  3. Remove adjusting keys or wrenches before turning plugging in.

Remember the folliwng:

Changing Grinding Wheels

Always check with a Manager after changing a wheel to verify that it is safe. Always use a Grinding Wheel rated to at least 3450 RPM.

  1. Unplug the Bench Grinder form the power outlet.
  2. Remove three Screws holding the Cover (2). Set aside Cover and Screws.
  3. Loosen Hex Screw (18) and move the Eye Shield above the Grinding Wheel.
  4. Remove the Tool Rest from the Wheel Guard (7) by removing Bolt (21) and Washer (20).
  5. While holding the Motor Rotor in place with a large, flat blade screwdriver, turn the Nut clockwise to loosen and remove Grinding Wheel and Flange. If removing the right Grinding Wheel, turn the Nut counterclockwise to loosen and remove.
  6. Replace Grinding Wheel with a new one rated to run to at least to the maximum speed of the Bench Grinder. Securely tighten Nut. CAUTION: Using a Grinding Wheel not rated to run at least to 3450 RPM could cause it to fly apart, causing injury, or damage to the Bench Grinder.

Operation

  1. Put on your safety glasses and plug in the power cord.
  2. Turn on the Bench Grinder by pressing the Switch to the ON position. The motor will start.
  3. When the Motor reaches full speed, bring the workpiece into the wheel gently, without jarring. Do not force the Bench Grinder
    • The workpiece will quickly become heated, therefore frequent quenching in water is required. Remove excess water before grinding again.
    • When grinding high speed steels such as drill and tool bits, avoid high temperature buildup as this can affect the temper of the steel.
    • For small workpieces such as drill bits or chisels, avoid applying pressure to the Grinding Wheel at a high angle that could cause the workpiece to become lodged between the Tool Rest and the Grinding Wheel.
  4. When you are done press the Switch to the OFF position.

Shutdown

  1. Verify that the Switch is in the OFF position.
  2. Unplug the machine from the power outlet.
  3. Recheck all nuts, bolts, and screws for tightness.

Cleanup

  1. Wipe down the Tool Rests and the external surfaces of the machine.
  2. Clean up your workstation.

Tips and Tricks

Dressing the Grinding Wheel (Managers Only)

New grinding wheels frequently are not true and during operation will often become grooved, glazed (build up), out of round, or misshapen. You will need to use a grinding wheel dresser for this operation.

  1. Stand to the side of the wheel for this operation.
  2. If the grinding wheel is new, let it run for a minute with no load. If the grinding wheel runs straight and true, you will not need to dress it prior to operation. If it does not, proceed with steps 3 or 4.
  3. If you are using a “pistol grip” dresser, grip the handle firmly with one hand and the arm of the dresser with the other. Allow the wheel to reach full speed. Use the tool rest to support your hand and the dresser, and evenly apply the dresser to all surfaces of the wheel. The wheel can be dressed in a few minutes.
  4. If you are using an “in-line” dresser, hold the handle firmly, put the dresser on the tool rest so that its wheels can move freely (i.e., the exposed part of the wheel should be facing up). Let the wheel reach full speed and apply the dresser evenly to all surfaces.

Ring-Test

A ring-test will verify that a disc is undamaged. Perform this test on the wheel (unless wheel is smaller than 4 inches or is an unusual shape) as follows:

  1. Suspend wheel using a pin or finger through the arbor hole.
  2. Tap the flat side of the wheel with a light non-metallic object.