Makita DGA504Z 18V 125mm Brushless Angle Grinder User Manual

Product Overview

The Makita DGA504Z is a powerful and efficient 18V 125mm (4.5 to 5-inch) brushless angle grinder designed for a variety of cutting and grinding applications. This bare unit is part of Makita's extensive 18V LXT Lithium-Ion series, offering cordless convenience and robust performance for professional and DIY users.

Figure 1: Makita DGA504Z 18V 125mm Brushless Angle Grinder (tool only, battery sold separately).

Key features include a brushless motor for increased efficiency and longer tool life, an electric brake that stops the grinding wheel in approximately 2 seconds for enhanced safety, and Active Feedback Technology (AFT) which automatically turns off the motor if the wheel is forced to stop. The LXT technology ensures faster charging, more run time, and efficient power management.

Safety Information

Always prioritize safety when operating power tools. Read and understand all safety warnings, instructions, illustrations, and specifications provided with this power tool. Failure to follow all instructions listed below may result in electric shock, fire, and/or serious injury.

• Wear appropriate personal protective equipment (PPE), including safety glasses, hearing protection, and gloves.
• Ensure the work area is 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.
• Keep children and bystanders away while operating a power tool. Distractions can cause you to lose control.
• Always use the correct guard for the application. The guard protects your hand from the rotating blade.
• Securely attach the side handle for better control during operation.

Setup

1. Attaching the Side Handle

The side handle can be screwed into either side of the grinder's head for optimal user comfort and control, depending on whether you are left-handed or right-handed. Simply align the threaded end of the handle with the desired hole and rotate clockwise until secure.

Figure 2: Attaching the side handle for improved grip and control.

2. Installing/Removing the Battery

To install the 18V LXT Lithium-Ion battery (sold separately), align the battery with the receptacle at the base of the grinder and slide it in until it clicks into place. To remove, press the release button on the battery pack and slide it out.

Figure 3: Battery indicator lights on the 18V LXT battery pack.

3. Installing the Grinding Wheel

Ensure the grinder is turned off and the battery is removed before installing or changing the grinding wheel. Press the spindle lock button to secure the spindle, then use the provided wrench to loosen the flange nut. Place the desired 4.5 to 5-inch grinding wheel onto the spindle, ensuring it is properly seated. Re-tighten the flange nut securely with the wrench. Always use wheels compatible with the grinder's specifications.

Figure 4: The grinding wheel and protective guard in place.

Operating Instructions

1. Powering On/Off

To turn on the grinder, slide the power switch forward until it locks into the ON position. To turn off, simply tap the switch back to the OFF position. The electric brake will stop the wheel quickly, typically within 2 seconds, for added safety.

2. Active Feedback Technology (AFT)

The DGA504Z is equipped with Active Feedback Technology (AFT). This safety feature automatically turns off the motor if the grinding wheel is suddenly forced to stop, such as when it binds or jams during operation. This helps to prevent kickback and potential injury.

3. General Operation

The grinder delivers a no-load speed of 8,500 RPM, providing ample power for demanding tasks. When operating, maintain a firm grip on both the main handle and the side handle. Apply steady, even pressure to the workpiece. Avoid excessive force, which can lead to binding or overheating. This tool is versatile and can be used for cutting metal, concrete, and other materials with the appropriate cutting blade.

Figure 5: The angle grinder in action, demonstrating its use for grinding metal.

Maintenance

Regular maintenance ensures the longevity and safe operation of your Makita DGA504Z angle grinder.

• Cleaning: After each use, clean the tool with a soft cloth to remove dust and debris. Pay special attention to the ventilation openings to prevent overheating.
• Brushless Motor: The brushless motor design means there are no carbon brushes to replace, reducing maintenance requirements and extending motor life. This design also allows the motor to run cooler and more efficiently.
• Inspecting Components: Periodically inspect the grinding wheel, guard, side handle, and power cord (if applicable, though this is cordless) for any damage or wear. Replace worn or damaged parts immediately.
• Battery Care: Store batteries in a cool, dry place. Follow charging instructions provided with your Makita charger.

Figure 6: Detail of the "Brushless" and "BL Motor" labeling, indicating the advanced motor technology.

Troubleshooting

If you encounter issues with your Makita DGA504Z, consider the following common solutions:

• Tool Not Starting:
  • Ensure the battery is fully charged and properly inserted. Check the battery indicator lights.
  • Verify the power switch is fully engaged in the ON position.
• Wheel Stops During Operation (Active Feedback Technology):
  • This is a safety feature. The motor turns off if the wheel is forced to stop due to binding or excessive load.
  • Release the power switch, remove the tool from the workpiece, and clear any obstructions. Re-engage the power switch to resume operation.
  • Reduce the pressure applied to the workpiece during grinding/cutting.
• Reduced Performance:
  • Check the battery charge level.
  • Ensure the grinding wheel is not worn out or damaged.
  • Clean any debris from the tool's ventilation openings.

Specifications

Figure 7: Product dimensions for the Makita DGA504Z.

Warranty and Support

For detailed warranty information and customer support, please refer to the official Makita website or contact Makita customer service directly. Protection plans may also be available for extended coverage, offering peace of mind beyond the standard manufacturer's warranty.

You can find more information and contact details on the Makita Store on Amazon.