1. Introduction and Overview
The DEWALT DCF850NT-XJ is an ultra-compact 18V XR Brushless Impact Driver designed for professional use. This tool delivers high performance in a small form factor, making it suitable for a wide range of fastening applications in construction, industrial, and automotive environments. This manual provides essential information for the safe and effective operation, maintenance, and troubleshooting of your impact driver.
Figure 1: DEWALT DCF850NT-XJ 18V XR Brushless Ultra-Compact Impact Driver with T-STAK case.
2. Safety Information
Always observe basic safety precautions when using power tools to reduce the risk of fire, electric shock, and personal injury. Read all instructions carefully before operating the tool.
- 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: Avoid body contact with earthed or grounded surfaces. Do not expose power tools to rain or wet conditions.
- Personal Safety: Always wear eye protection. Use hearing protection when operating the tool for extended periods. 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 battery pack from the power tool before making any adjustments, changing accessories, or storing power tools.
- Battery Pack Use and Care: This tool is supplied without a battery or charger. Use only DEWALT 18V XR battery packs and chargers. Refer to the battery and charger manuals for specific safety instructions.
3. Product Features
The DCF850NT-XJ impact driver incorporates several features designed for efficiency and user comfort:
- High Performance: Delivers up to 205 Nm of fastening torque.
- Ultra-Compact Design: The tool's head and body are compact and lightweight, allowing access to confined spaces.
- Brushless Motor: Provides increased power, efficiency, and durability compared to brushed motors.
- Integrated LED Ring Light: A 3-LED ring around the bit holder illuminates the work area for improved visibility.
- Variable Speed Trigger: Offers complete control over the speed for precise applications.
- 3-Mode Selection: Allows users to choose between different speed/torque settings, including a Precision Mode to prevent damage to materials and fasteners during delicate tasks.
Figure 2: Side view of the DCF850NT-XJ, highlighting its compact design.
4. Setup
4.1 Battery Installation
- Ensure the tool is switched off.
- Align the battery pack with the receptacle on the tool's base.
- Slide the battery pack into the tool until it clicks securely into place.
- To remove, press the battery release button and slide the battery pack out.
4.2 Bit Installation and Removal
- Installation: Pull the collar of the bit holder forward. Insert the hex shank accessory fully into the bit holder. Release the collar. The accessory should be securely locked.
- Removal: Pull the collar forward and pull the accessory out.
Figure 3: Angled view of the impact driver, showing the bit holder area.
4.3 Belt Clip Attachment
The tool includes a belt clip for convenient carrying. Attach the belt clip to either side of the tool using the provided screw.
5. Operating Instructions
5.1 Powering On/Off
To turn the tool on, depress the trigger switch. To turn the tool off, release the trigger switch.
5.2 Variable Speed Control
The trigger switch provides variable speed control. The further the trigger is depressed, the higher the speed of the tool. This allows for precise control during starting and driving fasteners.
5.3 Mode Selection
The DCF850NT-XJ features a 3-mode selector switch, typically located near the base of the handle. Each mode offers different speed and torque characteristics:
- Mode 1 (Low Speed/Torque): Ideal for smaller fasteners or delicate materials where precise control is needed.
- Mode 2 (Medium Speed/Torque): Suitable for general fastening applications.
- Mode 3 (High Speed/Torque): For heavy-duty fastening and maximum power.
- Precision Mode: This specialized mode helps prevent over-tightening and damage to fasteners or workpieces by automatically reducing speed and torque when the fastener is nearly seated.
5.4 LED Work Light
The integrated LED ring light activates when the trigger is partially depressed, illuminating the work surface. It remains on for a short period after the trigger is released.
Figure 4: The impact driver being used for automotive fastening.
Figure 5: The impact driver used for fastening in metal framing.
Figure 6: The impact driver driving fasteners into wood framing.
Figure 7: The impact driver used with a drilling accessory.
Figure 8: The impact driver driving a long screw into a wooden beam.
6. Maintenance
Regular maintenance ensures the longevity and optimal performance of your DEWALT impact driver.
- Cleaning: Keep the ventilation slots clean to prevent overheating. Use a soft brush or dry cloth to remove dust and debris. Do not use water or chemical cleaning agents.
- Inspection: Periodically inspect the tool for any damaged parts, loose screws, or worn components. Replace any damaged parts immediately.
- Storage: Store the tool in a dry, secure location out of reach of children. If storing for extended periods, remove the battery pack.
- Lubrication: This tool is factory lubricated and requires no additional lubrication.
7. Troubleshooting
If you encounter issues with your impact driver, refer to the following common troubleshooting steps:
| Problem | Possible Cause | Solution |
|---|---|---|
| Tool does not start | Battery not charged or improperly installed; Faulty switch | Ensure battery is fully charged and correctly inserted. If problem persists, contact service center. |
| Reduced power/performance | Low battery charge; Incorrect mode selected; Worn accessory | Recharge battery. Select appropriate mode. Replace worn bits/accessories. |
| Excessive vibration/noise | Loose components; Damaged accessory | Check for loose parts. Ensure accessory is properly installed and not damaged. If problem persists, discontinue use and contact service. |
For issues not covered here, or if troubleshooting steps do not resolve the problem, please contact an authorized DEWALT service center.
8. Specifications
| Specification | Value |
|---|---|
| Model Number | DCF850NT-XJ |
| Voltage | 18 Volts |
| Max Torque | 205 Newton-meters |
| No Load Speed | 3250 RPM |
| Power Output | 475 Watts |
| Head Type | Hexagonal |
| Product Dimensions (L x W x H) | 35 x 11.99 x 43 cm |
| Item Weight | 900 Grams |
| Material | Aluminum |
| Power Source | Battery Powered (Battery not included) |
9. Warranty and Support
DEWALT products are manufactured to high quality standards. For information regarding warranty coverage, please refer to the warranty card included with your product or visit the official DEWALT website. For technical support, spare parts, or service inquiries, please contact your local authorized DEWALT service center or dealer. Always provide the model number (DCF850NT-XJ) when seeking support.