Introduction
This instruction manual provides essential information for the safe and efficient operation, maintenance, and care of your Makita 9920 3" x 24" Belt Sander. Please read this manual thoroughly before using the tool to ensure proper handling and to prevent injury or damage.
The Makita 9920 Belt Sander is designed for fast and efficient material removal, suitable for various woodworking applications. Key features include a powerful motor, variable speed control, an auto-tracking belt system, and a design that allows for flush sanding.
Safety Instructions
Always follow basic safety precautions when using electric tools to reduce the risk of fire, electric shock, and personal injury. Keep this manual for future reference.
- Work Area Safety: Keep the 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 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.
- Personal Safety: Always wear eye protection. Use dust masks, non-skid safety shoes, hard hats, or hearing protection for appropriate conditions. Do not overreach. Keep proper footing and balance at all times. Dress properly. Do not wear loose clothing or jewelry. Keep your hair and clothing 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 before making any adjustments, changing accessories, or storing power tools.
- Dust Collection: The sander is equipped with a dust bag. Ensure it is properly attached and emptied regularly to maintain efficiency and a cleaner work environment.
Package Contents
Upon unpacking, verify that all items listed below are present and undamaged:
- Makita 9920 3" x 24" Belt Sander Unit
- Abrasive Belt (#80 grit, Part No. 742312-8C)
- Dust Bag (Part No. 122591-2)
- Instruction Guide (this manual)
Figure 1: Makita 9920 Belt Sander with included abrasive belt and dust bag.
Setup
Attaching the Dust Bag
- Locate the dust exhaust port on the side of the sander.
- Slide the dust bag collar onto the exhaust port until it is securely fitted.
- Ensure the dust bag is properly sealed to prevent dust leakage.
Figure 2: The dust bag attached to the sander's exhaust port.
Installing/Changing the Abrasive Belt
- Disconnect Power: Always unplug the sander from the power outlet before performing any adjustments or maintenance.
- Release Lever: Locate the belt tension release lever (typically on the side of the sander). Push or pull this lever to release the tension on the abrasive belt.
- Remove Old Belt: Carefully slide the old abrasive belt off the rollers.
- Install New Belt: Slide the new 3" x 24" abrasive belt onto the rollers. Ensure the directional arrow on the inside of the belt matches the arrow on the sander housing.
- Tension Belt: Return the belt tension release lever to its original position to secure the new belt.
- Check Tracking: Briefly plug in the sander and turn it on for a second to observe the belt tracking. The auto-tracking system should keep the belt centered. If manual adjustment is needed, refer to the operating section.
Operating Instructions
Powering On and Off
- Ensure the sander is plugged into a compatible 120V power outlet.
- To turn on, press the trigger switch. For continuous operation, engage the lock-on button (if present).
- To turn off, release the trigger switch. If locked on, press the trigger switch again to release the lock-on button.
Variable Speed Control
The Makita 9920 features a variable speed control dial, allowing you to adjust the belt speed from 690 to 1,440 feet per minute (ft./min.) to match the application requirements.
- Locate the variable speed control dial on the side of the sander.
- Rotate the dial to select the desired speed setting. Lower speeds are suitable for fine finishing or heat-sensitive materials, while higher speeds are for rapid material removal.
- The electronic speed control maintains constant speed under load, ensuring consistent performance.
Figure 3: Variable speed control dial for adjusting belt speed.
Auto-Tracking Belt System
The sander is equipped with an auto-tracking belt system that automatically centers the abrasive belt, eliminating the need for manual adjustments during operation.
Figure 4: The auto-tracking system ensures the belt remains centered.
Sanding Techniques
- General Sanding: Hold the sander firmly with both hands using the front grip and main handle. Apply even, moderate pressure. Allow the weight of the tool to do most of the work. Move the sander smoothly and consistently across the workpiece in the direction of the wood grain.
- Flush Sanding: The innovative design of the 9920 allows for sanding flush to a wall or adjacent surface using both the nose and side of the sander. This is particularly useful for working in confined spaces or along edges.
Figure 5: The sander's design facilitates flush sanding against vertical surfaces.
Figure 6: Proper two-hand grip for operating the belt sander.
Maintenance
Regular maintenance ensures optimal performance and extends the lifespan of your Makita 9920 Belt Sander.
- Dust Bag Emptying: Empty the dust bag frequently, especially when sanding materials that produce a lot of dust. A full dust bag reduces collection efficiency and can lead to dust buildup within the tool.
- Cleaning: Periodically clean the exterior of the sander with a soft, damp cloth. Use compressed air to clear dust from ventilation openings. Avoid using solvents or harsh chemicals. Pay attention to the internal mechanisms, as excessive wood dust can accumulate and cause heat buildup.
- Belt Inspection: Inspect the abrasive belt before each use for wear, tears, or damage. Replace worn belts promptly to maintain sanding effectiveness and prevent damage to the workpiece or tool.
- Cord Inspection: Check the power cord for any cuts, fraying, or damage. Do not use the tool if the cord is damaged.
Troubleshooting
This section addresses common issues you might encounter with your Makita 9920 Belt Sander.
| Problem | Possible Cause | Solution |
|---|---|---|
| Sander does not turn on. | No power supply; damaged cord; faulty switch. | Check power outlet and cord. If cord is damaged, have it replaced by an authorized service center. Ensure switch is fully engaged. |
| Belt not tracking correctly. | Improper belt installation; worn belt. | Ensure belt is installed with the correct directional arrow. Replace worn belts. The auto-tracking system should correct minor deviations. |
| Reduced sanding efficiency. | Worn abrasive belt; dust bag full. | Replace the abrasive belt. Empty the dust bag. |
| Excessive dust in work area. | Dust bag not attached properly; dust bag full; dust bag damaged. | Ensure dust bag is securely attached. Empty the dust bag. Replace damaged dust bag. |
| Tool overheating. | Blocked ventilation; excessive load; internal dust buildup. | Clear ventilation openings. Reduce sanding pressure. Clean internal components if accessible, or seek professional service for internal cleaning. |
| Dust bag clasp slips off. | Loose clasp mechanism. | Secure the clasp firmly. If it continues to slip, consider using small binder clips to reinforce the closure. |
Specifications
| Feature | Specification |
|---|---|
| Model Number | 9920 |
| Belt Size | 3" x 24" |
| Belt Speed (No Load) | 690 - 1,440 ft./min. (Variable Speed) |
| Amperage (120V) | 8.8 Amps |
| Overall Length | 13-1/8" |
| Net Weight | 9.9 lbs. |
| Power Cord Length | 16.4 ft. |
| Noise Level | 84 dB |
| Voltage | 120 Volts |
| Power Source | Corded Electric |
Warranty Information
Every Makita tool is thoroughly inspected and tested before leaving the factory. If you are not satisfied with any Makita tool within 30 days of purchase, return it for a replacement or refund.
Each Makita tool is warranted to be free of defects from workmanship and materials for a period of ONE YEAR from the date of original purchase. Should any trouble develop during this one-year period, return the COMPLETE tool, freight prepaid, to one of Makita's Factory or Authorized Service Centers.
For complete details regarding warranty terms and conditions, please visit the official Makita website: makitatools.com.
Customer Support
For further assistance, technical support, or to locate an authorized service center, please contact Makita customer service:
- Phone: 800/4-MAKITA (800/462-5482)
- Website: makitatools.com
