Bosch GBH 7-46 Rotary Hammer Drill User Manual

1. Introduction

This manual provides essential information for the safe and efficient operation, maintenance, and troubleshooting of your Bosch GBH 7-46 Rotary Hammer Drill. The GBH 7-46 DE is a 7 kg rotary hammer with a 1350 W power input, designed for drilling concrete from 12-45 mm and chiseling tasks. It features a no-load speed of 0-250 rpm, an impact rate of 1350-2800 ipm, and an impact force of 4-13 / 15 J, weighing 7.9 kg.

2. Safety Instructions

Always observe general power tool safety warnings and instructions to prevent electric shock, fire, and serious injury.

• Work Area Safety: Keep your work area clean and well-lit. 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. Avoid body contact with earthed or grounded surfaces. Do not expose power tools to rain or wet conditions.
• Personal Safety: Always wear eye protection, hearing protection, and a dust mask when operating the tool. Dress properly; avoid loose clothing or jewelry. Secure 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: Be aware of potential kickback, especially when drilling into hard materials or if the bit binds. Maintain a firm grip on the tool.
• Vibration: Prolonged use can cause vibration-related injuries. Take regular breaks and use anti-vibration gloves if available.

3. Product Overview

The Bosch GBH 7-46 is a robust rotary hammer drill designed for heavy-duty applications. Familiarize yourself with its main components before operation.

Figure 3.1: Bosch GBH 7-46 Rotary Hammer Drill with an SDS max drill bit installed. This image shows the main body, auxiliary handle, and the chuck for bit insertion.

• Main Handle: Ergonomically designed for comfortable grip and control.
• Auxiliary Handle: Provides additional stability and control, especially during heavy drilling or chiseling. It can be rotated for optimal positioning.
• SDS max Chuck: For quick and secure insertion of SDS max drill bits and chisels.
• Mode Selector Switch: Allows selection between drilling, hammer drilling, and chiseling modes.
• On/Off Switch: Controls power to the tool.
• Depth Stop: Used to set the desired drilling depth.

Figure 3.2: Side view of the Bosch GBH 7-46 Rotary Hammer Drill, highlighting the robust casing and handle design.

4. Setup

4.1 Attaching the Auxiliary Handle

Loosen the auxiliary handle clamp and slide the handle onto the tool's neck. Adjust its position for comfortable and secure grip, then tighten the clamp firmly.

4.2 Installing SDS max Bits

1. Clean the shank of the SDS max bit and apply a thin layer of grease.
2. Pull back the locking sleeve on the chuck.
3. Insert the bit into the chuck, rotating it slightly until it engages.
4. Release the locking sleeve. Pull on the bit to ensure it is securely locked. The bit should have a small amount of axial play, which is normal for SDS max systems.

4.3 Setting the Depth Stop

Insert the depth stop into its designated hole. Adjust it to the desired drilling depth by sliding it in or out, then secure it. The tip of the drill bit should extend beyond the depth stop by the desired drilling depth.

5. Operating Instructions

5.1 Selecting Operating Mode

Rotate the mode selector switch to choose the appropriate function:

• Hammer Drilling: For drilling in concrete, masonry, and stone with impact.
• Chiseling: For chiseling, demolition, and breaking work.
• Rotation Stop (for chiseling): Allows the chisel to be rotated and locked in various positions.

5.2 Starting and Stopping

To start the tool, press the On/Off switch. To stop, release the switch. For continuous operation, press the On/Off switch and then press the lock-on button (if available). To release, press the On/Off switch again.

5.3 General Operation Tips

• Always hold the tool firmly with both hands.
• Apply steady, even pressure. Do not lean into the tool excessively; let the hammer mechanism do the work.
• When drilling, ensure the drill bit is perpendicular to the workpiece.
• For chiseling, position the chisel correctly before starting.
• Be aware of hidden electrical cables, gas pipes, and water pipes. Use a suitable detector before drilling or chiseling.

Figure 5.1: A worker demonstrating the use of the Bosch GBH 7-46 Rotary Hammer Drill for chiseling concrete, wearing appropriate safety gear.

Figure 5.2: The Bosch GBH 7-46 Rotary Hammer Drill positioned on a concrete surface, ready for heavy-duty work.

6. Maintenance

Regular maintenance ensures the longevity and optimal performance of your rotary hammer drill. Always disconnect the tool from the power supply before performing any maintenance.

• Cleaning: Keep the ventilation openings clean to prevent overheating. Regularly clean the tool housing with a soft, damp cloth. Do not use solvents.
• Chuck Maintenance: Clean the SDS max chuck regularly and apply a small amount of special grease to the bit shank to ensure smooth operation and prevent wear.
• Carbon Brushes: If applicable, have carbon brushes checked and replaced by a qualified service technician when worn.
• Cord Inspection: Regularly inspect the power cord for damage. If damaged, have it replaced by an authorized service center.

7. Troubleshooting

Before attempting any repairs, always disconnect the tool from the power supply.

8. Specifications

9. Warranty and Support

For warranty information, service, or technical support, please refer to the documentation provided with your purchase or visit the official Bosch website. Keep your proof of purchase for warranty claims.

Official Bosch Website: www.bosch-pt.com