Bosch GBH 2-28 D Professional Rotary Hammer User Manual

1. Safety Instructions

Always observe the following safety guidelines when operating the Bosch GBH 2-28 D Rotary Hammer to prevent injury and damage to the tool.

• Work Area Safety: Keep the work area clean and well-lit. Cluttered or dark areas invite accidents.
• Electrical Safety: Ensure the power cord is undamaged. Do not expose power tools to rain or wet conditions.
• Personal Safety: Always wear eye protection, hearing protection, and suitable work gloves. Secure loose clothing and long hair.
• 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.
• Kickback Protection: The overload clutch protects the user and the machine in case of overload or binding, preventing abrupt blockage.
• Vibration: Prolonged use may cause vibration-related injuries. Take regular breaks and use anti-vibration gloves if necessary.

2. Product Overview

The Bosch GBH 2-28 D is a professional SDS Plus rotary hammer designed for heavy-duty drilling and chiseling tasks in concrete, masonry, and wood. Familiarize yourself with its components.

Figure 2.1: Front view of the Bosch GBH 2-28 D Rotary Hammer, showing the main body, SDS Plus chuck, auxiliary handle, and depth stop.

Key Components:

• SDS Plus Chuck: For quick and secure bit changes.
• Mode Selector Switch: To select between drilling, hammer drilling, and chiseling modes.
• Trigger Switch: For power activation and variable speed control.
• Lock-on Button: For continuous operation.
• Auxiliary Handle: Provides additional grip and control.
• Depth Stop: For precise drilling depth adjustment.
• Ball Grommet: Prevents power cord breaks.

3. Setup

Before operating the rotary hammer, ensure proper assembly and attachment of accessories.

3.1 Attaching the Auxiliary Handle

1. Loosen the auxiliary handle by turning it counter-clockwise.
2. Slide the handle over the chuck and onto the tool's neck.
3. Adjust the handle to a comfortable and secure position.
4. Tighten the handle by turning it clockwise until it is firmly secured.

Figure 3.1: Detail of the auxiliary handle, which provides enhanced grip and control during operation.

3.2 Inserting the Depth Stop

1. Insert the depth stop into the designated hole on the auxiliary handle.
2. Adjust the depth stop to the desired drilling depth by sliding it in or out.
3. Secure the depth stop by tightening the auxiliary handle.

3.3 Inserting SDS Plus Drill Bits

1. Clean the shank of the drill bit and apply a thin layer of grease.
2. Push the drill bit into the SDS Plus chuck until it locks into place.
3. Pull the drill bit to check if it is securely seated. The SDS Plus system allows for slight axial play, which is normal.

4. Operating Instructions

Understand the various modes and controls for effective and safe operation.

4.1 Mode Selection

Figure 4.1: Side view highlighting the mode selector switch for different operations.

• Drilling Mode (Rotation Only): Use for drilling in wood, metal, and plastics. Set the mode selector to the drill symbol.
• Hammer Drilling Mode (Rotation with Hammering): Ideal for drilling in concrete and masonry. Set the mode selector to the hammer drill symbol.
• Chiseling Mode (Hammering Only): For light chiseling work. Set the mode selector to the chisel symbol. Ensure the tool is unplugged before changing chisel position.

4.2 Variable Speed Control

The trigger switch provides infinitely variable speed control. Pressing the trigger further increases the speed. This allows for precise control, especially when starting a drill hole or working with different materials.

4.3 Lock-on Button

For continuous operation, press the trigger switch and then engage the lock-on button. To release, press the trigger switch again.

4.4 General Operation Tips

Figure 4.2: An operator demonstrating proper two-handed grip while drilling into a concrete surface.

• Always hold the tool firmly with both hands using the main handle and auxiliary handle.
• Apply steady, even pressure. Do not lean into the tool excessively.
• Allow the tool to reach full speed before engaging the workpiece.
• For deep holes, periodically withdraw the drill bit to clear debris.

5. Maintenance

Regular maintenance ensures the longevity and optimal performance of your Bosch GBH 2-28 D Rotary Hammer.

• Cleaning: After each use, clean the tool's ventilation slots and housing with a soft, dry cloth. Do not use water or chemical cleaners.
• Chuck Maintenance: Keep the SDS Plus chuck clean and lightly greased to ensure smooth bit insertion and removal.
• Cord Inspection: Regularly inspect the power cord for any signs of damage. Replace immediately if damaged.
• Storage: Store the tool in a dry, secure location, out of reach of children. Use the provided carrying case for protection.

6. Troubleshooting

Refer to this section for common issues and their potential solutions.

If the problem persists after attempting these solutions, please contact an authorized Bosch service center.

7. Specifications

Technical data for the Bosch GBH 2-28 D Professional Rotary Hammer.

8. Warranty and Support

Bosch power tools are manufactured to the highest quality standards. For information regarding warranty coverage, service, or technical support, please refer to the warranty card included with your product or visit the official Bosch Power Tools website.

Online Resources: www.bosch-pt.com