1. Introduction
Thank you for choosing the Bosch GBM 400 or GBM 400KL Electric Drill. This professional-grade tool is designed for efficient drilling and screwing tasks in various materials. This manual provides essential information for safe operation, proper setup, and maintenance to ensure optimal performance and longevity of your tool. Please read these instructions carefully before using the drill and keep them for future reference.
2. General Safety Instructions
WARNING! Read 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.
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. Power tools create sparks which may ignite the dust or fumes.
- Keep children and bystanders away while operating a power tool. Distractions can cause you to lose control.
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. Unmodified plugs and matching outlets will reduce risk of electric shock.
- Avoid body contact with earthed or grounded surfaces, such as pipes, radiators, ranges, and refrigerators. There is an increased risk of electric shock if your body is earthed or grounded.
- Do not expose power tools to rain or wet conditions. Water entering a power tool will increase the risk of electric shock.
- Do not abuse the cord. Never use the cord for carrying, pulling, or unplugging the power tool. Keep cord away from heat, oil, sharp edges, or moving parts. Damaged or entangled cords increase the risk of electric shock.
Personal Safety
- Stay alert, watch what you are doing, and use common sense when operating a power tool. Do not use a power tool while you are tired or under the influence of drugs, alcohol, or medication.
- Use personal protective equipment. Always wear eye protection. Protective equipment such as a dust mask, non-skid safety shoes, hard hat, or hearing protection used for appropriate conditions will reduce personal injuries.
- Prevent unintentional starting. Ensure the switch is in the off-position before connecting to power source, picking up, or carrying the tool.
- Remove any adjusting key or wrench before turning the power tool on. A wrench or a key left attached to a rotating part of the power tool may result in personal injury.
- Do not overreach. Keep proper footing and balance at all times. This enables better control of the power tool in unexpected situations.
3. Product Overview
The Bosch GBM 400 series electric drills are versatile tools designed for various drilling and screwing applications. They feature a powerful 400W motor and variable speed control for precision work.
Models
- GBM 400 KL: Features a keyless self-locking chuck (0.8-10mm range) for quick and easy bit changes without additional tools.
- GBM 400: Equipped with a traditional keyed metal chuck (1-10mm range) for tighter clamping and high concentricity, requiring a chuck key for bit changes.
Key Features
- 400W Motor: Provides improved power for efficient drilling and screwing.
- Variable Speed Control: Allows for precise speed adjustment up to 2800 RPM, suitable for different materials and tasks.
- Constant Speed Lock: Enables continuous operation at a set speed, reducing user fatigue during prolonged use.
- Forward and Reverse Rotation Switch: Facilitates both drilling and efficient removal of screws.
- Big Air Outlet: Designed for faster heat dissipation and reduced operational noise, contributing to extended tool life.
- Dual Insulation Design: Enhances user safety by preventing electric shock, even if drilling into live cables.
Visual Overview
4. Specifications
| Attribute | Specification |
|---|---|
| Brand Name | Bosch |
| Model Number | BS-GBM400 (GBM 400 / GBM 400KL) |
| Rated Input Power | 400W |
| Rated Voltage | 220V (Applicable 200-240V) |
| No-Load Speed | 0-2800rpm |
| Chuck Range (GBM 400 KL) | 0.8-10mm (Keyless Self-locking) |
| Chuck Range (GBM 400) | 1-10mm (Keyed Metal Chuck) |
| Max Drilling Diameter (Wood) | 20mm |
| Max Drilling Diameter (Steel) | 10mm |
| Max Drilling Diameter (Aluminium) | 13mm |
| Net Weight | 1.3 KG |
| Dimensions (Approx.) | 240mm x 195mm |
| Power Source | AC (Corded Electric) |
| Motor Type | Optimized Carbon Brush Motor |
| Certification | CE, RoHS |
5. Setup and Bit Installation
Proper installation of drill bits is crucial for safety and effective operation. Always ensure the drill is unplugged before changing bits.
For Key-locking Chuck (GBM 400)
- Rotate the chuck counterclockwise to loosen the jaws.
- Insert the desired drill bit into the chuck, ensuring it is seated firmly.
- Insert the chuck key into the side hole and rotate clockwise to fasten the chuck securely around the drill bit. Remove the key before operation.
For Keyless Self-locking Chuck (GBM 400 KL)
- Rotate the front part of the chuck counterclockwise to open the jaws.
- Insert the desired drill bit into the chuck, ensuring it is seated firmly.
- Rotate the front part of the chuck clockwise to tighten the jaws securely around the drill bit.
6. Operating Instructions
Always wear appropriate personal protective equipment, including eye protection, before operating the drill.
Power On/Off and Variable Speed
- Connect the drill to a 220V (200-240V) power outlet.
- To start the drill, press the trigger switch. The speed is variable depending on how far you press the trigger.
- For continuous operation at a constant speed, press the lock button while the trigger is pressed. Release the trigger to disengage the lock.
- To turn off the drill, release the trigger switch. If the lock button is engaged, press the trigger fully and then release it to disengage the lock and turn off the tool.
Forward and Reverse Rotation
The forward/reverse switch is located near the trigger. Push it to the left for forward rotation (drilling and screwing in) and to the right for reverse rotation (unscrewing).
Applications
- Drilling:
- Wood: Use appropriate wood drill bits. Max drilling diameter: 20mm.
- Metal: Use appropriate metal drill bits. Max drilling diameter: 10mm (steel), 13mm (aluminium).
- Tile/Light Masonry: Use appropriate masonry drill bits. While the tool is primarily a rotary drill, it can handle light masonry tasks.
- Screwing: Use appropriate screwdriver bits with the forward and reverse rotation function.
Video 1: Bosch GBM 400 Electric Drill product demonstration, showing drilling, screwing, and chuck types.
7. Maintenance
Regular maintenance ensures the longevity and safe operation of your Bosch electric drill.
- Cleaning: Regularly clean the ventilation openings to prevent dust buildup, which can cause overheating. Use a soft brush or compressed air. Do not use water or chemical cleaners.
- Chuck Maintenance: Keep the chuck jaws clean and free of debris. For keyed chucks, ensure the key is stored safely.
- Carbon Brushes: The optimized carbon brush motor is designed for extended service life. If you notice a significant drop in performance or excessive sparking, it may be time for brush inspection or replacement by a qualified service technician.
- Cord Inspection: Periodically inspect the power cord for any signs of damage, cuts, or fraying. Replace damaged cords immediately to prevent electrical hazards.
- Storage: Store the drill in a dry, secure location, out of reach of children and away from direct sunlight or extreme temperatures.
8. Troubleshooting
| Problem | Possible Cause | Solution |
|---|---|---|
| Drill does not start | No power supply; Faulty power cord; Trigger switch malfunction | Check power outlet and connections. Inspect power cord for damage. If issues persist, contact service. |
| Loss of power during operation | Overload; Worn carbon brushes; Insufficient voltage | Reduce load. Check power supply. Have carbon brushes inspected/replaced by service. |
| Excessive vibration or noise | Loose drill bit; Damaged chuck; Internal component issue | Ensure bit is securely fastened. Inspect chuck for damage. If severe, seek professional service. |
| Drill bit slips in chuck | Chuck not tightened sufficiently; Worn chuck jaws; Incorrect bit size | Retighten chuck. Ensure bit shank is clean. If chuck is worn, it may need replacement. |
| Overheating | Blocked ventilation; Prolonged heavy use; Overload | Clean ventilation slots. Allow tool to cool down. Avoid continuous heavy loads. |
9. User Tips
- Chuck Type Selection: If you frequently change bits for different tasks, the GBM 400 KL with its keyless self-locking chuck offers greater convenience. For applications requiring maximum grip and precision, the GBM 400 with its keyed metal chuck is ideal.
- Drilling Masonry: While the product is described as an "Electric Hammer Drill" in some features and can drill into tile/brick, it is primarily a rotary drill. For heavy-duty concrete or stone drilling, a dedicated hammer drill with a more robust impact mechanism would be more suitable. For light masonry, ensure you use appropriate masonry drill bits.
- Bit Compatibility: Always use drill bits and screwdriver bits that are compatible with the chuck's clamping range (0.8-10mm for KL, 1-10mm for standard) to prevent slippage and damage.
- Variable Speed Control: Utilize the variable speed trigger for starting holes slowly and increasing speed as needed. Lower speeds are generally better for screwing and drilling into harder materials, while higher speeds are efficient for softer materials.
10. Warranty and Support
DREMEL&BOSCH provides quality service for your product.
Warranty Information
This product comes with a 2-year warranty. The warranty covers manufacturing defects and ensures the product functions as intended under normal use.
Exclusions from Warranty:
- Artificial damage or damage due to violent use.
- Repairs performed without authorization.
- Parts subject to normal wear and tear.
- Refund orders (warranty applies to product repair/replacement).
For quality problems, please contact DREMEL customer service. Provide relevant videos and product warranty label photos. Customer service will address your problem within 24 working hours.
Certifications
The Bosch GBM 400 series electric drills are certified with CE and RoHS, ensuring compliance with European safety, health, and environmental protection standards.
