DEWALT DCM571 String Trimmer / Brush Cutter User Manual

Technical Data

DCM571 Specifications

• Voltage (UK & Ireland): 54V DC
• Power Output: 220-240 W
• RPM: 0-5100 / 0-5500 /min
• Cutting Swath Size: 380 mm
• Weight (without battery pack): 4.6 kg

Brush Cutter Mode

• Type: Tri-Blade Brush Knife, Grass Cutting Blade, 4T Grass Cutting Blade
• RPM: 0-5100 / 0-5500 /min
• Cutting Swath Size: 255 mm

Noise and Vibration Values (Brush Cutter Mode, EN ISO 11806-1)

• Emission Sound Pressure Level (LPA): 78.5 dB(A)
• Sound Power Level (LWA): 94 dB(A)
• Uncertainty (K): 1.8 dB(A)
• Vibration Emission (Handle): <2.5 m/s²
• Vibration Emission (Auxiliary Handle): 10.1 m/s²
• Uncertainty (K): 1.5 m/s²

Noise and Vibration Values (String Trimmer Mode, EN 50636-2-91)

• Emission Sound Pressure Level (LPA): 79 dB(A)
• Sound Power Level (LWA): 94 dB(A)
• Uncertainty (K): 1.0 dB(A)
• Vibration Emission (Handle): <2.5 m/s²
• Vibration Emission (Auxiliary Handle): 2.6 m/s²
• Uncertainty (K): 1.5 m/s²

Note on Vibration: The declared vibration emission level is measured according to standardized tests and can be used for preliminary assessment. Actual exposure may vary based on application, accessories, and maintenance. It's recommended to take breaks and implement safety measures to reduce exposure.

Batteries & Chargers (Sold Separately)

EC Declaration of Conformity

DEWALT declares that the products described under Technical Data comply with:

• Machinery Directive 2006/42/EC, EN60335-1:2012 + A11:2014, EN50636-2-91:2014, EN ISO 11806-1:2011.
• 2000/14/EC, Lawn Trimmer, L ≤ 50 cm, Annex VI.
• Directives 2014/30/EU and 2011/65/EU.

Contact for technical file compilation:

Markus Rompel, Director Engineering
DEWALT, Richard-Klinger-Straße 11, D-65510, Idstein, Germany
Date: 10.11.2016

Acoustic Power Level (2000/14/EC): LPA (measured sound pressure) 79 dB(A) (uncertainty K = 1.0 dB(A)), LWA (guaranteed sound power) 96 dB(A).

Safety Guidelines Definitions

⚠️ DANGER: Indicates an imminently hazardous situation which, if not avoided, will result in death or serious injury.

⚠️ WARNING: Indicates a potentially hazardous situation which, if not avoided, could result in death or serious injury.

⚠️ CAUTION: Indicates a potentially hazardous situation which, if not avoided, may result in minor or moderate injury.

ℹ️ NOTICE: Indicates a practice not related to personal injury which, if not avoided, may result in property damage.

⚡ Denotes risk of electric shock.

? Denotes risk of fire.

Safety Instructions

General Warnings: Always follow basic safety precautions when using power tools to reduce the risk of fire, electric shock, personal injury, and material damage. Read all instructions carefully before operating the machine and keep them for future reference.

Safe Operating Practices

Training

• Read instructions carefully and familiarize yourself with controls and correct use.
• Never allow children or untrained persons to use the machine. Local regulations may restrict operator age.
• The operator is responsible for accidents or hazards to others or their property.

Preparation

• Before use, visually inspect the machine for damaged or missing guards/shields.
• Never operate the machine with people, children, or pets nearby.
• The brush cutter blade has sharp edges; wear gloves when handling it.

Operation

• Always wear eye protection and stout shoes.
• Avoid using in bad weather, especially during lightning.
• Use only in daylight or good artificial light.
• Never operate with damaged or missing guards/shields.
• Switch on the motor only when hands and feet are away from the cutting means.
• Always disconnect the machine from the power supply (remove battery) when unattended, before clearing blockages, before maintenance/cleaning, after striking an object, or if abnormal vibration occurs.
• Be careful of injury to feet and hands from cutting means.
• Keep ventilation openings clear of debris.
• Kickback Risk (Brush Cutter): If the brush cutter contacts a solid object (tree trunk, branch, rock), the unit can kick back. Remove objects that may cause kickback.
• Check for loose fasteners and damaged parts.

Maintenance and Storage

• Disconnect power (remove battery) before maintenance or cleaning.
• Use only manufacturer-recommended parts and accessories.
• Inspect and maintain regularly; have repairs done by an authorized repairer.
• Store out of reach of children when not in use.
• Use blade cover for metal blades during transport and storage.
• Clean before storing, using guards on cutting attachments with metal blades.

Additional Safety Instructions for Grass Trimmers / Brush Cutters

⚠️ WARNING: Cutting elements continue to rotate after the motor is switched off.

• Wear long trousers to protect legs.
• Check cutting path for sticks, stones, wire, and obstacles before use.
• Use the appliance in an upright position with the cutting line near the ground. Never switch on in any other position.
• Move slowly; be aware that freshly cut grass is damp and slippery.
• Do not work on steep slopes; work across slopes.
• Never cross gravel paths or roads while the appliance is running.
• Never touch the cutting line while the appliance is running.
• Do not put the appliance down until the cutting line has come to a complete standstill.
• Use only the appropriate type of cutting line; never use metal cutting line or fishing line.
• Keep hands and feet away from the cutting line and blade, especially when switching on the motor.
• Before use and after any impact, check for wear or damage and repair as necessary.
• Take care against injury from line length trimming devices. After extending new cutter line, return the machine to its normal operating position before switching on.
• Close supervision is necessary when used near children.
• This appliance is not intended for use by young or infirm persons without supervision.
• This appliance is not to be used as a toy.
• Use only in dry locations; do not allow the appliance to become wet.
• Do not immerse the appliance in water.
• Do not open the body casing; no user-serviceable parts inside.
• Do not operate in explosive atmospheres (flammable liquids, gases, dust).
• When storing or transporting in a vehicle, place in the boot or restrain to prevent movement.
• Store in a dry, well-ventilated place out of reach of children.
• Children should not have access to stored appliances.

Safety of Others

• This appliance is not intended for use by persons (including children) with reduced physical, sensory, or mental capabilities, or lack of experience/knowledge, unless supervised by a person responsible for their safety.
• Children must be supervised to ensure they do not play with the appliance.

Residual Risks

Ensure good footing on slopes, do not overreach, and keep balance. Always walk, do not run.

Additional risks may arise from misuse or prolonged use. Even with safety regulations and devices, some residual risks cannot be avoided:

• Injuries from touching rotating/moving parts.
• Injuries when changing parts, blades, or accessories.
• Injuries from prolonged use (take regular breaks).
• Impairment of hearing.
• Health hazards from breathing dust.

Electrical Safety

Ensure battery pack voltage corresponds to the rating plate. Ensure charger voltage matches mains voltage.

Your DEWALT charger is double insulated (EN60335); no earth wire is required.

⚠️ WARNING: 115V units require a fail-safe isolating transformer with an earth screen. If the supply cord is damaged, it must be replaced by DEWALT service.

Mains Plug Replacement (U.K. & Ireland Only)

Dispose of old plug safely. Connect brown lead to live terminal, blue lead to neutral terminal. ⚠️ WARNING: No connection to the earth terminal.

Using an Extension Cable

Use an approved extension cable suitable for the charger's power input (see Technical Data). Minimum conductor size 1 mm², maximum length 30 m. Unwind cable reels completely.

Chargers

DEWALT chargers require no adjustment and are designed for easy operation.

Important Safety Instructions for All Battery Chargers

⚠️ WARNING: Shock hazard. Do not allow liquid inside the charger.

⚠️ WARNING: Use of a residual current device (30mA or less) is recommended.

⚠️ CAUTION: Burn hazard. Charge only DEWALT rechargeable batteries. Other types may burst.

⚠️ CAUTION: Children should be supervised.

ℹ️ NOTICE: Keep charging contacts away from foreign material (e.g., steel wool, foil). Always unplug the charger when no battery pack is inserted. Unplug before cleaning.

• DO NOT attempt to charge with chargers other than those in this manual.
• Chargers are not intended for uses other than charging DEWALT batteries.
• Do not expose charger to rain or snow.
• Pull by plug, not cord, when disconnecting.
• Ensure cord is not a tripping hazard.
• Do not use an extension cord unless absolutely necessary.

Charger Operation

Do not place objects on the charger or block ventilation slots. Place away from heat sources. Ventilated through top and bottom slots.

Do not operate with damaged cords/plugs. Take to authorized service center if damaged.

Never connect two chargers together. Charger is designed for standard 230V household power.

Charging a Battery (Fig. B)

1. Plug charger into outlet before inserting battery.

2. Insert battery pack 14 into charger, ensuring it is fully seated. Red charging light will blink.

3. Charge completion indicated by solid red light. Remove battery by pressing release button 15.

Note: Charge battery fully before first use for maximum performance.

Charger Indicators

• Charging: Red light blinking.
• Fully Charged: Red light solid.
• Hot/Cold Pack Delay: Red light blinking, yellow light on. Charger resumes when battery reaches appropriate temperature.

Faulty battery packs will not charge and may be indicated by charger lights. This could also indicate a charger problem. Take charger and battery to an authorized service center if a problem is indicated.

Hot/Cold Pack Delay

The charger automatically suspends charging if the battery pack is too hot or too cold, ensuring maximum battery life. Cold battery packs charge slower.

The DCB118 charger has an internal fan for cooling. Ensure fan operates and ventilation slots are clear.

Electronic Protection System

XR Li-Ion tools have a system to protect the battery pack against overloading, overheating, or deep discharge. The tool will automatically turn off if this system engages. Recharge the battery pack if this occurs.

Wall Mounting

Chargers can be wall-mounted. Locate within reach of an outlet, away from obstructions. Use charger's back as a template for mounting screws.

Charger Cleaning Instructions

⚠️ WARNING: Disconnect charger from AC outlet before cleaning. Clean exterior with a cloth or soft brush. Do not use water or cleaning solutions. Never let liquid get inside.

Battery Packs

Important Safety Instructions for All Battery Packs

When ordering replacement packs, include catalog number and voltage.

Battery packs are not fully charged out of the carton. Read safety instructions before use.

• Do not charge or use battery in explosive atmospheres.
• Never force battery pack into charger. Do not modify packs.
• Charge only in DEWALT chargers.
• Do NOT splash or immerse in water or other liquids.
• Do not store or use where temperatures exceed 40°C (104°F).
• Do not incinerate battery packs, even if damaged; they can explode.
• If battery contents contact skin, wash immediately with soap and water. If in eyes, rinse with water for 15 minutes. Seek medical attention if needed.
• ⚠️ WARNING: Battery liquid may be flammable.
• ⚠️ WARNING: Never attempt to open the battery pack. Return damaged packs to a service center for recycling.
• ⚠️ WARNING: Fire hazard. Do not store or carry battery packs so metal objects can contact terminals.
• ⚠️ CAUTION: When not in use, place tool on its side on a stable surface.

Transportation

⚠️ WARNING: Fire hazard. Ensure battery terminals are protected and insulated from conductive materials during transport.

DEWALT batteries comply with shipping regulations (UN, IATA, IMDG, ADR). Lithium-ion cells are tested per UN Manual of Tests and Criteria.

Shipments with batteries exceeding 100 Wh may require Class 9 Hazardous Material classification. DEWALT does not recommend air shipping lithium-ion battery packs alone. Combo kits may be air shipped as excepted if battery pack is ≤ 100 Whr.

It is the shipper's responsibility to consult and comply with latest regulations.

Transporting the FLEXVOLTTM Battery

FLEXVOLTTM batteries have two modes: Use and Transport.

• Use Mode: Operates as 18V battery in 18V products, or 54V in 54V/108V products.
• Transport Mode: Achieved by attaching the cap. This disconnects cells, resulting in 3 batteries with a lower Wh rating, potentially exempting them from certain shipping regulations.

Storage Recommendations

• Store in a cool, dry place away from direct sunlight and extreme temperatures. Store at room temperature for optimum performance.
• For long storage, store a fully charged battery pack in a cool, dry place out of the charger.

Note: Battery packs should not be stored completely depleted.

Labels on Charger and Battery Pack

Pictographs may include: Read instruction manual, See Technical Data for charging time, Do not probe with conductive objects.

Battery Type

The DCM571 operates on a 54 volt battery pack (e.g., DCB546, DCB547).

Package Contents

• 1 String trimmer
• 1 Auxiliary handle
• 4 Auxiliary handle screws
• 1 Strap
• 1 Guard
• 4 Guard screws
• 1 Brush cutter blade
• 1 Brush cutter nut
• 1 Brush cutter clamp washer
• 1 Brush cutter drive washer
• 5 Cotter pins
• 1 Nut wrench
• 1 Rod, lock
• 1 Blade cover
• 1 Battery (not for DCM571N)
• 1 Charger (not for DCM571N)
• 1 Instruction manual

Check for damage to the tool, parts, or accessories that may have occurred during transport.

Markings on Tool

Pictograms on the tool indicate:

• Read instruction manual before use.
• Wear ear protection.
• Wear eye protection.
• Do not expose to rain or high humidity.
• Switch off tool and remove battery before maintenance.
• Wear head protection.
• Wear slip-resistant footwear.
• Wear slip-resistant gloves.
• Keep people and animals at least 15 m away from the work area.
• Do not use circular metal blades.
• Beware of thrown objects.
• Beware of blade thrust.
• Keep bystanders away.

Directive 2000/14/EC guaranteed sound power: 96 dB(A) LWA.

Date Code Position (Fig. U): Printed into the housing, includes year of manufacture (e.g., 2016).

Description (Fig. A)

⚠️ WARNING: Never modify the power tool or any part of it.

Key Components:

• 1 Variable speed trigger
• 2 Lock-off lever
• 3 Lock-off tab
• 4 Handle
• 5 Speed control switch
• 6 Auxiliary handle
• 7 Motor housing
• 8 Trimmer pole
• 9 Strap mount
• 10 Strap
• 11 Guard
• 12 Spool housing
• 13 Battery housing
• 14 Battery pack
• 15 Battery release button
• 16 Brush cutter blade
• 17 Nut wrench
• 18 Blade cover

Diagram Description (Fig. A): An exploded view showing the main components of the string trimmer/brush cutter, including the motor housing, trimmer pole, battery housing, guard, auxiliary handle, and cutting head assembly.

Intended Use

Designed for professional trimming applications. Do not use under wet conditions, in the presence of flammable liquids/gases, or allow children to contact the tool. Supervision is required for inexperienced operators.

This appliance is not intended for use by young children or infirm persons without supervision. It is also not for persons with diminished physical, sensory, or mental abilities, or lack of experience/knowledge, unless supervised. Children should never be left alone with the product.

Assembly and Adjustments

⚠️ WARNING: Turn tool off and disconnect battery pack before making adjustments or installing/removing attachments. Accidental start-up can cause injury.

⚠️ WARNING: Use only DEWALT battery packs and chargers.

Inserting and Removing the Battery Pack (Fig. C, D)

To Install: Align battery pack 14 with the rails inside the tool and slide until it clicks firmly into place.

To Remove: Press the release button 15 and pull the battery pack out.

Diagram Description (Fig. C, D): Shows the battery pack 14 being aligned with and inserted into the battery housing 13 of the tool.

Fuel Gauge Battery Packs (Fig. E)

Some battery packs have a fuel gauge with three green LED lights indicating charge level. Press the fuel gauge button 19 to display the level. If the level is below the usable limit, the gauge will not illuminate, and the battery needs recharging.

Note: Fuel gauge is an indication of charge, not tool functionality.

Diagram Description (Fig. E): Illustrates the fuel gauge button 19 and the three LED indicators showing battery charge status.

Assembly (Fig. F - I)

Removing Spool Housing (Fig. F, G)

1. Insert rod 46 through hole 21 in drive washer 20 and into hole 22 in motor housing 7.
2. Turn spool housing 12 clockwise (Fig. G).
3. Remove spool housing and drive washer.

Diagram Description (Fig. F, G): Shows the process of inserting a rod to aid in removing the spool housing 12 and drive washer 20.

Attaching Guard (Fig. H, I)

⚠️ WARNING: Never operate without the guard firmly in place.

1. Remove spool housing 12.
2. Slide tab 23 of the guard under lip 24 of the motor housing 7, then lower the back of the guard.
3. Securely tighten the 4 guard screws 25 with wrench 17 (Fig. I).
4. Replace spool housing.

Diagram Description (Fig. H, I): Illustrates attaching the guard by sliding its tab under the motor housing lip and securing it with screws.

Attaching Spool Housing (Fig. I, J)

1. Slide string trimmer drive washer (small) 20 over bolt 26 so hole 21 aligns with hole 22 in motor housing 7.
2. Rotate washer and motor housing until holes align with notch 27 in guard 11.
3. Insert screwdriver through holes, thread spool housing counterclockwise, and tighten onto bolt.

Diagram Description (Fig. I, J): Shows attaching the drive washer and spool housing to the motor housing, aligning holes and notches.

Attaching Blade (Fig. K)

⚠️ WARNING: Risk of injury. Brush cutter blade has sharp edges. Wear gloves.

1. Remove spool housing 12 and drive washer 20.
2. Slide brush cutter drive washer (large) 28 over bolt 26 so hole 29 aligns with hole 22 in motor housing 7.
3. Place brush cutter blade 16 on top of drive washer, with non-cutting edge 30 aligned with the drive washer hole.
4. Slide brush cutter clamp washer 31 on top of the blade.
5. Screw brush cutter nut 32 onto bolt 26 with wrench 17 and tighten securely.
6. Slide cotter pin 33 through the hole in the bolt.

Diagram Description (Fig. K): Details the steps for attaching the brush cutter blade 16, including washers 28, 31, nut 32, and cotter pin 33.

Attaching Auxiliary Handle (Fig. L)

1. Place auxiliary handle 6 onto trimmer pole 8 above the middle label.
2. Slide bracket 34 into the bottom of the handle.
3. Thread handle bolts 35 through the bracket and into the handle.
4. Tighten bolts 35 with wrench 17. Ensure handle is securely attached. Adjust position by loosening bolts if necessary.

Diagram Description (Fig. L): Shows how to attach the auxiliary handle 6 using bracket 34 and bolts 35.

Operation

Instructions for Use

⚠️ WARNING: Always observe safety instructions and applicable regulations.

⚠️ WARNING: Turn tool off and disconnect battery before making adjustments or removing/installing accessories.

Proper Hand Position (Fig. O)

Hold the tool with one hand on the handle 4 and the other hand on the auxiliary handle 6.

Diagram Description (Fig. O): Illustrates the correct hand placement on the tool's handle and auxiliary handle for safe operation.

Switching On

Push lock-off tab 3 forward, squeeze lock-off lever 2, then squeeze variable speed trigger 1.

To turn off, release the trigger, lock-off lever, and tab.

Speed Control Switch

Use the speed control switch 5 to select speed:

• "LO" Position: Push switch forward toward auxiliary handle for extended runtime on larger jobs.
• "HI" Position: Pull switch back toward battery housing for higher RPM and faster cutting in heavier growth.

Note: "HI" mode decreases runtime compared to "LO" mode.

Trimming / Brush Cutting (Fig. N, O)

Angle the trimmer and swing side to side (Fig. N).

Maintain a minimum distance of 610 mm between the guard and your feet (Fig. O).

⚠️ WARNING: Keep the rotating string roughly parallel to the ground (tilted no more than 30 degrees). This trimmer is not an edger. DO NOT tilt the trimmer so the string or blade spins at a right angle to the ground, as flying debris can cause serious injury.

Diagram Description (Fig. N): Shows the side-to-side swinging motion for trimming/brush cutting.

Diagram Description (Fig. O): Demonstrates proper hand position and the minimum distance to maintain from feet.

Bump Feed Trimmer Line Feed

⚠️ WARNING: Never bump the unit when the brush cutter assembly is attached.

Your trimmer uses 2.032 mm diameter nylon line. Line feeds automatically when you gently bump the trimmer on the ground while running at normal speed.

Note: Extending nylon line beyond 330 mm can negatively affect performance and potentially damage the motor.

Helpful Cutting Tips

• Use the tip of the string for cutting; do not force the string head into uncut grass.
• Wire fences, stone, brick, curbs, and wood can cause extra string wear.
• Do not allow the spool cap to drag on ground or surfaces.
• In long growth, cut from the top down, not exceeding 304.8 mm high.
• Keep the trimmer tilted toward the area being cut.
• The trimmer cuts best when passing from left to right, avoiding throwing debris at the operator.
• Avoid trees and shrubs, as bark, wood moldings, siding, and fence posts can be damaged by the string.

Replacement Accessories

⚠️ WARNING: Use only DEWALT recommended accessories to reduce the risk of injury.

• Replacement Line: Model No. DT20650 (2mm), DT20651 (2mm), DT20652 (2.5mm). DT20650/51 recommended for optimal performance.
• Replacement Blades: Model No. DT20653 (255mm Tri-Blade Brush Knife), DT20654 (255mm Grass Cutting Blade), DT20655 (230mm 4T Grass Cutting Blade).

Replacing the Cutting Line (Fig. P-S)

⚠️ CAUTION: Cut line so it just reaches the blade.

1. Remove battery.
2. Turn spool 36 clockwise to unlock (Fig. P). White nub 37 rotates away from spool window 38.
3. Pull spool straight out.
4. Clean spool and housing.
5. Wind new line in the channel of the spool closest to holding slots 39 (Fig. Q).
6. Place end of cutting line 40 into retaining hole 41.
7. Wind line onto spool in the direction of the arrow.
8. When line reaches holding slots, cut it to approximately 106 mm.
9. Push line into holding slots on one side to hold first line while winding second line.
10. Repeat for the second line.
11. ⚠️ CAUTION: Ensure cutting line is present in both sections of the spool (Fig. R).
12. Secure string with thumbs/fingers on holding slots and feed ends through holes 43 on either side of the head in spool housing 12 (Fig. S).
13. Align white nubs 37 with spool recesses 42. Align holding slots 39 with holes 43.
14. Push spool into housing and turn counterclockwise to lock. Ensure white nub appears in spool window 38. Prevent line from unraveling.
15. Pull both ends of the line to release from holding slots. Cut line if it extends past the guard blade.

Diagram Description (Fig. P): Shows turning the spool 36 to unlock it, indicated by the white nub 37.

Diagram Description (Fig. Q): Illustrates winding new line into the spool channel and placing the end into the retaining hole 41.

Diagram Description (Fig. R): Shows the correct way cutting line should be present in both sections of the spool.

Diagram Description (Fig. S): Details feeding the line ends through the holes 43 in the spool housing 12 and aligning the spool.

Maintenance

The tool is designed for long operation with minimal maintenance. Proper care and regular cleaning ensure satisfactory operation.

⚠️ WARNING: Turn tool off and disconnect battery before making adjustments or removing/installing accessories.

1. Keep air intake slots 44 (Fig. T) clean to avoid overheating.
2. To keep trimmer line in top condition, store spare line in a plastic bag with a tablespoon of water.
3. Clean plastic parts with mild soap and a damp rag.
4. Periodically touch up the sharpness of the line cutter on the guard with a file.

The charger and battery pack are not serviceable.

Diagram Description (Fig. T): Highlights the air intake slots 44 on the motor housing.

Lubrication

Your power tool requires no additional lubrication.

Cleaning

⚠️ WARNING: Blow dirt and dust from main housing with dry air. Wear eye protection and dust mask.

⚠️ WARNING: Never use solvents or harsh chemicals on non-metallic parts. Use only water and mild soap. Never let liquid get inside the tool or immerse any part in liquid.

Optional Accessories

⚠️ WARNING: Use of accessories not offered by DEWALT could be hazardous. Only DEWALT recommended accessories should be used.

Protecting the Environment

Products and batteries marked with this symbol [recycle symbol] must not be disposed of with normal household waste. Recycle electrical products and batteries according to local provisions. More information at www.2helpU.com.

Rechargeable Battery Pack

Recharge the battery pack when it fails to produce sufficient power. At the end of its technical life, discard it responsibly:

• Run the battery pack down completely, then remove it from the tool.
• Li-Ion cells are recyclable; take them to your dealer or a local recycling station.

Contact Information

For country-specific contact details, please refer to the back of the manual or the following list: