DEWALT 4 1/2 Inch (115mm) 900W Angle Grinder User Manual

1. Safety Instructions

Always follow basic safety precautions when using electrical tools to reduce the risk of fire, electric shock, and personal injury. Read all instructions before operating this tool.

General Power Tool Safety Warnings

• Work Area Safety: Keep work area clean and well lit. Cluttered or dark areas invite accidents. Do not operate power tools in explosive atmospheres, such as in the presence of flammable liquids, gases or dust.
• Electrical Safety: Power tool plugs must match the outlet. Never modify the plug in any way. Do not expose power tools to rain or wet conditions.
• Personal Safety: Stay alert, watch what you are doing and use common sense when operating a power tool. Always wear eye protection. Use safety equipment such as dust mask, non-skid safety shoes, hard hat, or hearing protection for appropriate conditions.
• Tool Use and Care: Do not force the power tool. Use the correct power tool for your application. Disconnect the plug from the power source before making any adjustments, changing accessories, or storing power tools.

2. Product Overview

The DEWALT DWE4120B Angle Grinder is a powerful and compact tool designed for efficient cutting, grinding, and material removal tasks. Its ergonomic design ensures comfortable handling during extended use.

Key Features:

• 900W Motor: Provides robust power for demanding applications.
• 12,000 RPM Rotation: High speed for quick and efficient material removal.
• Versatile Applications: Ideal for cutting, grinding, and removing material from metals, masonry, and concrete.
• Compact and Ergonomic: Designed for comfortable use and reduced fatigue.
• Safety Trigger: Enhances user safety during operation.
• Two-Position Side Handle: Offers improved control and comfort for various tasks.

Figure 2.1: DEWALT DWE4120B Angle Grinder with side handle and grinding disc.

Figure 2.2: Internal view showcasing the powerful motor and gear housing of the angle grinder.

3. Setup

3.1 Attaching the Side Handle

The side handle can be attached to either side of the gear case for optimal comfort and control, depending on the application and user preference.

• Locate the threaded holes on both sides of the gear case.
• Screw the side handle firmly into the desired position.

Figure 3.1: Angle grinder with the side handle properly installed.

3.2 Installing/Changing Grinding Discs

Always ensure the tool is unplugged from the power source before installing or changing discs.

• Press and hold the spindle lock button to prevent the spindle from rotating.
• Using the spanner wrench provided, loosen the outer flange nut by turning it counter-clockwise.
• Remove the outer flange nut and the old disc.
• Place the new disc onto the inner flange, ensuring it is centered.
• Replace the outer flange nut and tighten it clockwise with the spanner wrench while holding the spindle lock button.
• Release the spindle lock button.

Figure 3.2: Process of changing the grinding disc using the provided spanner wrench.

4. Operating the Angle Grinder

4.1 Powering On/Off

• To turn the tool ON, slide the switch forward.
• To turn the tool OFF, slide the switch backward.

4.2 Grinding and Cutting Techniques

Always ensure proper ventilation and wear appropriate personal protective equipment (PPE), including eye protection, gloves, and hearing protection.

• Grinding: Hold the grinder firmly with both hands. Apply light, even pressure, allowing the tool's speed to do the work. Maintain a consistent angle to the workpiece.
• Cutting: Use a cutting disc. Position the disc perpendicular to the workpiece. Make shallow passes, gradually increasing depth. Avoid twisting or binding the disc in the cut.

Figure 4.1: Angle grinder in operation, demonstrating proper technique for grinding metal surfaces.

5. Maintenance

Regular maintenance ensures the longevity and optimal performance of your DEWALT Angle Grinder. Always unplug the tool before performing any maintenance.

5.1 Cleaning

• Keep the ventilation openings clear and free of dust.
• Use a soft brush or dry cloth to clean the tool's exterior. Do not use water or chemical cleaners.
• Periodically blow compressed air through the motor housing to remove dust and debris.

5.2 Carbon Brush Inspection/Replacement

Carbon brushes wear down over time and should be inspected periodically. Refer to a qualified service center for brush replacement if necessary.

6. Troubleshooting

7. Specifications

Figure 7.1: Product dimensions for the DEWALT DWE4120B Angle Grinder.

8. Warranty and Support

DEWALT products are manufactured to high quality standards and are guaranteed for professional use. For specific warranty details, please refer to the warranty card included with your product or visit the official DEWALT website.

Customer Support:

For technical assistance, service, or to locate an authorized service center, please contact DEWALT customer support through their official channels. Keep your purchase receipt as proof of purchase for warranty claims.

You can find more information and support on the official DEWALT website: www.dewalt.com