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User Manual for Craftsman CMCF921 20V Max Mid-Range Impact Wrench
Quick guide for the Craftsman CMCF921 20V Max Mid-Range Impact Wrench. Includes setup, battery charging, operation, maintenance, and safety instructions.
Quick answers from the manual
Quick answer
- The Craftsman CMCF921 is a 20V Max cordless impact wrench. It is operated via a variable speed trigger and features two speed modes (0-900 RPM and 0-1900 RPM). p. 1, 10
Key actions
- Install battery p. 10
- Select speed p. 10
First start
- Charge the battery fully before first use. p. 6, 8
Problems and fixes
Battery not charging
Check charger connection, ensure temperature is appropriate, or take to an authorized service center if the light stays off.
p. 8, 9Maintenance and reset
- Clean air vents weekly with clean, dry air. p. 11
Technical specifications
| Parameter | Value | Meaning | Pages |
|---|---|---|---|
| Low Mode | 0-900 RPM | Normal Impacting | p. 10 |
| High Mode | 0-1900 RPM | High Speed Impacting | p. 10 |
Where to find it in the PDF
- Safety Instructions p. 2, 3, 4, 5
- Operation p. 10
- Maintenance p. 11
Table of contents
Manual images
Click an image to enlargeQuick guide from the manual
This manual provides essential safety, operation, and maintenance instructions for the Craftsman CMCF921 20V Max Mid-Range Impact Wrench. Always read all safety warnings before use. Ensure the battery is fully charged before the first use and that you are using only impact-ready accessories.
Product description
The Craftsman CMCF921 is a cordless impact wrench designed for fastening and drilling applications in wood, metal, and concrete. It features a variable speed trigger, a worklight, and a speed selector for different applications.
Operation
Installing and removing the battery: Align the battery pack with the rails inside the tool handle and slide it in until it is firmly seated. To remove, press the battery release button and pull the pack out.
Variable speed trigger: The tool is turned on and off by pulling and releasing the trigger. The farther the trigger is depressed, the higher the speed. The tool is equipped with a brake that stops the chuck immediately when the trigger is released.
Forward/reverse control: The button determines the rotational direction and serves as a lock-off. The center position locks the tool in the off position.
Speed selector: Allows switching between Low Mode (0-900 RPM) and High Mode (0-1900 RPM).
Usage
Always use impact-ready accessories. Inspect accessories for cracks before use. Fastening torque is affected by voltage, accessory size, bolt size, material, and fastening time. Always check torque with a torque wrench for critical applications.
Maintenance
Keep air vents clean by blowing out dirt and dust with clean, dry air at least once a week. Use only a cloth dampened with water and mild soap for cleaning non-metallic parts. Do not use solvents.
VersaTrack and belt hook
The tool includes a VersaTrack hang hook and a belt hook. Both can be attached to either side of the tool using the provided screw. Ensure the screw is securely tightened before use. Do not suspend the tool overhead using these hooks.
Manufacturer information
CRAFTSMAN
Practical help
Common problems
Tool will not start
Ensure the battery is fully charged and properly seated in the tool handle. Check that the forward/reverse button is not in the center (locked) position.
Battery will not charge
Check that the charger is plugged into a working outlet. Ensure the battery is within the recommended temperature range (65°F–75°F is ideal). If the light stays off, the battery may be faulty.
Before use
- Ensure the battery pack is fully charged.
- Wear ANSI Z87.1 approved eye protection and hearing protection.
- Inspect all accessories for cracks or damage.
- Ensure the work area is clean and well-lit.
- Verify the forward/reverse button is set to the desired direction.
Images and diagrams
- Fig A: Overview of the tool, including trigger, speed selector, worklight, and anvil.
- Fig C: Instructions for installing and removing the battery pack.
- Fig E: Installation of the belt hook and VersaTrack hang hook.
Model compatibility
- Use only Craftsman 20V Max battery packs and chargers.
- Use only impact-ready accessories.
- VersaTrack accessories are sold separately.
Manual page author
Michael Turner
Technical manual editor
Reviews PDF manuals for structure, safety notes, and practical product details so readers can find the right information quickly.