Introduction
The Bosch GBH 3-28 E is a powerful rotary hammer drill designed for demanding drilling and chiseling tasks. Featuring an SDS-plus tool holder, it delivers maximum power with minimal vibrations, ensuring high drilling progress and 20% more chiseling performance compared to other rotary hammers in its class. This manual provides essential information for safe and efficient operation, setup, maintenance, and troubleshooting.
Image of the Bosch GBH 3-28 E rotary hammer drill, showcasing its robust design and ergonomic handle. This tool is engineered for heavy-duty applications.
Key Features:
- Maximum power output for demanding tasks.
- SDS-plus tool holder with dust protection.
- Reduced vibrations for comfortable operation.
- High drilling progress and superior chiseling performance.
Safety Instructions
Always observe the following safety precautions when operating the Bosch GBH 3-28 E rotary hammer drill to prevent electric shock, fire, and serious injury.
General Power Tool Safety Warnings:
- Work Area Safety: Keep your 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 use any adapter plugs with earthed (grounded) power tools. Avoid body contact with earthed or grounded surfaces such as pipes, radiators, ranges, and refrigerators.
- Personal Safety: Always wear eye protection. Use hearing protection when operating for extended periods. Wear a dust mask if operations create dust. Dress properly; do not wear loose clothing or jewelry. Keep hair, clothing, and gloves away from moving parts.
- 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 and/or remove the battery pack from the power tool before making any adjustments, changing accessories, or storing power tools.
- Service: Have your power tool serviced by a qualified repair person using only identical replacement parts. This will ensure that the safety of the power tool is maintained.
Package Contents
Upon unpacking, please ensure all items listed below are present and in good condition:
- Bosch GBH 3-28 E Rotary Hammer Drill
- Auxiliary Handle
- Depth Stop
- Transport Case
- User Manual (this document)
Setup
Before operating the rotary hammer drill, follow these steps for proper setup:
1. Attaching the Auxiliary Handle:
- Loosen the auxiliary handle by turning it counter-clockwise.
- Slide the handle over the collar of the tool to the desired position.
- Tighten the handle by turning it clockwise until secure. Ensure it is firmly fixed for safe operation.
2. Inserting the Depth Stop:
- Insert the depth stop into the designated hole on the auxiliary handle.
- Adjust the depth stop to the required drilling depth.
- Secure the depth stop by tightening the auxiliary handle.
3. Inserting SDS-plus Drill Bits/Chisels:
- Clean the shank of the drill bit or chisel and apply a thin layer of grease.
- Insert the tool into the SDS-plus tool holder with a slight twisting motion until it locks.
- Pull on the tool to check if it is securely locked. A slight axial play is normal and necessary for the hammer mechanism.
Operating Instructions
Familiarize yourself with the controls and functions before beginning work.
1. Mode Selector Switch:
The GBH 3-28 E features a mode selector switch to choose between different operating modes:
- Drilling (Rotation only): For drilling in wood, metal, ceramics, and plastics without hammer action.
- Hammer Drilling (Rotation with Hammer Action): For drilling in concrete, masonry, and stone.
- Chiseling (Hammer Action only): For light chiseling work, such as removing tiles or breaking small sections of concrete.
Note: Always switch modes only when the tool is switched off to prevent damage to the gearbox.
2. Switching On/Off:
- To switch on, press the On/Off switch.
- To switch off, release the On/Off switch.
- For continuous operation, press the On/Off switch and then press the lock-on button. To switch off, press the On/Off switch again.
3. Speed Preselection:
The rotary hammer drill features a speed preselection wheel. Adjust the speed according to the material and the size of the drill bit/chisel. Lower speeds are generally used for larger diameters and harder materials.
4. Working with the Tool:
- Drilling: Apply moderate pressure. Let the tool do the work. Excessive pressure will not speed up drilling but can damage the drill bit and the tool.
- Chiseling: Hold the tool firmly with both hands. Guide the chisel along the desired line.
- Overload Protection: The tool is equipped with an overload clutch. If the drill bit jams, the drive to the spindle is interrupted. Always hold the tool firmly with both hands to counteract the reaction forces.
Maintenance
Regular maintenance ensures the longevity and optimal performance of your Bosch GBH 3-28 E rotary hammer drill.
1. Cleaning:
- Always disconnect the plug from the power outlet before any cleaning or maintenance work.
- Keep the ventilation slots clean to prevent overheating.
- Clean the tool holder regularly. Remove dust and debris.
- Wipe the tool housing with a soft, damp cloth. Do not use harsh cleaning agents or solvents.
2. Lubrication:
The SDS-plus tool holder requires periodic lubrication. Apply a thin layer of special grease to the shank of the drill bits and chisels before insertion to ensure smooth operation and reduce wear.
3. Carbon Brushes:
The carbon brushes are wear parts. If the motor sparks excessively or the tool loses power, the carbon brushes may need replacement. This should be performed by an authorized Bosch service center.
4. Storage:
Store the tool in a dry, secure place, out of reach of children. Use the transport case for protection.
Troubleshooting
This section addresses common issues you might encounter with your Bosch GBH 3-28 E rotary hammer drill.
| Problem | Possible Cause | Solution |
|---|---|---|
| Tool does not start. | No power supply; faulty switch; worn carbon brushes. | Check power connection. Ensure switch is fully pressed. Contact service center for brush replacement. |
| Reduced drilling/chiseling performance. | Worn drill bit/chisel; incorrect mode selection; insufficient lubrication of tool holder. | Replace worn accessories. Select correct operating mode. Lubricate tool shank. |
| Excessive vibration or noise. | Loose auxiliary handle; damaged accessory; internal fault. | Tighten auxiliary handle. Inspect and replace damaged accessories. Contact service center. |
| Tool overheats. | Blocked ventilation slots; continuous heavy load; worn motor components. | Clean ventilation slots. Allow tool to cool down. Avoid prolonged heavy use. Contact service center. |
Specifications
Detailed technical specifications for the Bosch GBH 3-28 E Rotary Hammer Drill:
- Brand: Bosch
- Model Number: GBH 3-28 E
- Manufacturer Part Number: 611239703
- Power Source: Corded Electric
- Voltage: 230 Volts
- Maximum Power: 800 Watts
- No-load Speed: 900 RPM
- Product Weight: 3.5 Kilograms
- Material: Metal
- Color: Black
- Special Features: Transmission, Long lifespan, Robust design
- Drill Type: Rotary Hammer Drill
- Tool Holder: SDS-plus
- Global Trade Item Number (GTIN): 03165140220255
Warranty and Support
Warranty information for the Bosch GBH 3-28 E rotary hammer drill is typically provided with the purchase documentation. Please refer to your sales receipt or the warranty card included in the product packaging for specific terms and conditions.
For technical support, service, or spare parts, please contact Bosch customer service or visit their official website. Ensure you have your model number (GBH 3-28 E) and serial number (if applicable) ready when contacting support.
Bosch Official Website: www.bosch-professional.com
