DEG 125-D
DEG 125-P
DEG 150-D
DEG 150-P

Explanation of signs used

Warnings

Warnings alert persons to hazards that occur when handling or using the product. The following signal words are used in combination with a symbol:

	DANGER! Draws attention to imminent danger that will lead to serious personal injury or fatality.
	WARNING! Draws attention to a potential hazard that could lead to serious personal injury or fatality.
	CAUTION! Draws attention to a potentially dangerous situation that could lead to slight personal injury or damage to the equipment or other property.

Symbols

The following symbols are used in this document:

	Read the operating instructions before use.
	Instructions for use and other useful information

Symbols on the product

The following symbols are used on the product:

	Wear eye protection.
	Revolutions per minute
	Revolutions per minute
	Rated speed
	Diameter
	Protection class II (double-insulated)

Characters in illustrations

The illustrations in these operating instructions are intended to promote a better understanding and may deviate from the actual version of the product.

	These numbers refer to the corresponding illustrations found at the beginning of these operating instructions.
	The numbering reflects the order of the work steps in the illustration and may deviate from the numbering of work steps in the text.
	Item reference numbers are used in the overview illustration and refer to the numbers used in the product overview section.

Product information

Hilti products are designed for professional use and may be operated, serviced and maintained only by trained, authorized personnel. This personnel must be informed of any particular hazards that may be encountered. The product described and its ancillary equipment may present hazards when used incorrectly by untrained personnel or when used not as directed.
The type designation and serial number are printed on the type identification plate.

• Write down the serial number in the table below. Always quote this information when you contact a Hilti representative or Hilti Service to enquire about the product.
  Product information
  

Product information

Angle grinder	DEG 125-D/P | DEG 150-D/P
Generation	01
Serial no.

Safety instructions

The safety rules given in the following section contain all general safety rules for electric tools which, in accordance with the applicable standards, require to be listed in the operating instructions. Accordingly, some of the rules listed may not be relevant to this electric tool.

General power tool safety warnings

WARNING
Read all safety warnings and all instructions. Failure to follow the warnings and instructions may result in electric shock, fire and/or serious injury.
Save all warnings and instructions for future reference.
The term “power tool” in the warnings refers to your mains-operated (corded) power tool or battery-operated (cordless) power tool.
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.
  
• When operating a power tool outdoors, use an extension cord suitable for outdoor use. Use of a cord suitable for outdoor use reduces the risk of electric shock.
  
• If operating a power tool in a damp location is unavoidable, use a residual current device (RCD) protected supply. Use of an RCD reduces 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. A moment of inattention while operating power tools may result in serious personal injury.
  
• Use personal protective equipment. Always wear eye protection. Protective equipment such as 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 and/or battery pack, picking up or carrying the tool. Carrying power tools with your finger on the switch or energising power tools that have the switch on invites accidents.
  
• 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.
  
• Dress properly. Do not wear loose clothing or jewellery. Keep your hair, clothing and gloves away from moving parts. Loose clothes, jewellery or long hair can be caught in moving parts.
  
• If devices are provided for the connection of dust extraction and collection facilities, ensure these are connected and properly used. Use of dust collection can reduce dust-related hazards.
  

Power tool use and care

• Do not force the power tool. Use the correct power tool for your application. The correct power tool will do the job better and safer at the rate for which it was designed.
  
• Do not use the power tool if the switch does not turn it on and off. Any power tool that cannot be controlled with the switch is dangerous and must be repaired.
  
• Disconnect the plug from the power source and/or the battery pack from the power tool before making any adjustments, changing accessories, or storing power tools. Such preventive safety measures reduce the risk of starting the power tool accidentally.
  
• Store idle power tools out of the reach of children and do not allow persons unfamiliar with the power tool or these instructions to operate the power tool. Power tools are dangerous in the hands of untrained users.
  
• Maintain power tools. Check for misalignment or binding of moving parts, breakage of parts and any other condition that may affect the power tool’s operation. If damaged, have the power tool repaired before use. Many accidents are caused by poorly maintained power tools.
  
• Keep cutting tools sharp and clean. Properly maintained cutting tools with sharp cutting edges are less likely to bind and are easier to control.
  
• Use the power tool, accessories and tool bits etc. in accordance with these instructions, taking into account the working conditions and the work to be performed. Use of the power tool for operations different from those intended could result in a hazardous situation.
  

Service

• Have your power tool serviced by a qualified repair person using only identical replacement parts. This will ensure that the safety of the power tool is maintained.
  

Safety warnings common for grinding, sanding, wire brushing, polishing or abrasive cutting-off operations:

• This power tool is intended to function as a grinder or cut-off tool. 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.
  
• Operations such as sanding, wire brushing or polishing are not recommended to be performed with this power tool. Operations for which the power tool was not designed may create a hazard and cause personal injury.
  

• Do not use accessories which are not specifically designed and recommended by the tool manufacturer. Just because the accessory can be attached to your power tool, it does not assure safe operation.
  
• The rated speed of the accessory must be at least equal to the maximum speed marked on the power tool. Accessories running faster than their rated speed can break and fly apart.
  
• The outside diameter and the thickness of your accessory must be within the capacity rating of your power tool. Incorrectly sized accessories cannot be adequately guarded or controlled.
  
• Threaded mounting of accessories must match the grinder spindle thread. For accessories mounted by flanges, the arbour hole of the accessory must fit the locating diameter of the flange. Accessories that do not match the mounting hardware of the power tool will run out of balance, vibrate excessively and may cause loss of control.
  
• Do not use a damaged accessory. Before each use inspect the accessory such as abrasive wheels for chips and cracks, backing pad for cracks, tear or excess wear, wire brush for loose or cracked wires. If power tool or accessory is dropped, inspect for damage or install an undamaged accessory. After inspecting and installing an accessory, position yourself and bystanders away from the plane of the rotating accessory and run the power tool at maximum no-load speed for one minute. Damaged accessories will normally break apart during this test time.
  
• Wear personal protective equipment. Depending on application, use face shield, safety goggles or safety glasses. As appropriate, wear dust mask, hearing protectors, gloves and workshop apron capable of stopping small abrasive or workpiece fragments. The eye protection must be capable of stopping flying debris generated by various operations. The dust mask or respirator must be capable of filtrating particles generated by your operation. Prolonged exposure to high intensity noise may cause hearing loss.
  
• Keep bystanders a safe distance away from work area. Anyone entering the work area must wear personal protective equipment. Fragments of workpiece or of a broken accessory may fly away and cause injury beyond immediate area of operation.
  

• Hold the power tool by insulated gripping surfaces only, when performing an operation where the cutting accessory may contact hidden wiring or its own cord. Cutting accessory contacting a "live" wire may make exposed metal parts of the power tool "live" and could give the operator an electric shock.
  

• Position the cord clear of the spinning accessory. If you lose control, the cord may be cut or snagged and your hand or arm may be pulled into the spinning accessory.
  
• Never lay the power tool down until the accessory has come to a complete stop. The spinning accessory may grab the surface and pull the power tool out of your control.
  
• Do not run the power tool while carrying it at your side. Accidental contact with the spinning accessory could snag your clothing, pulling the accessory into your body.
  
• Regularly clean the power tool’s air vents. The motor’s fan will draw the dust inside the housing and excessive accumulation of powdered metal may cause electrical hazards.
  
• Do not operate the power tool near flammable materials. Sparks could ignite these materials.
  

• Do not use accessories that require liquid coolants. Using water or other liquid coolants may result in electrocution or shock.
  

Kickback and related warningsKickback is a sudden reaction to a pinched or snagged rotating wheel, backing pad, brush or any other accessory. Pinching or snagging causes rapid stalling of the rotating accessory which in turn causes the uncontrolled power tool to be forced in the direction opposite of the accessory’s rotation at the point of the binding.
For example, if an abrasive wheel is snagged or pinched by the workpiece, the edge of the wheel that is entering into the pinch point can dig into the surface of the material causing the wheel to climb out or kick out. The wheel may either jump toward or away from the operator, depending on direction of the wheel’s movement at the point of pinching. Abrasive wheels may also break under these conditions.
Kickback is the result of power tool misuse and/or incorrect operating procedures or conditions and can be avoided by taking proper precautions as given below.

• Maintain a firm grip on the power tool and position your body and arm to allow you to resist kickback forces. Always use auxiliary handle, if provided, for maximum control over kickback or torque reaction during start-up. The operator can control torque reactions or kickback forces, if proper precautions are taken.
  
• Never place your hand near the rotating accessory. Accessory may kickback over your hand.
  
• Do not position your body in the area where power tool will move if kickback occurs. Kickback will propel the tool in direction opposite to the wheel’s movement at the point of snagging.
  
• Use special care when working corners, sharp edges etc. Avoid bouncing and snagging the accessory. Corners, sharp edges or bouncing have a tendency to snag the rotating accessory and cause loss of control or kickback.
  
• Do not attach a saw chain woodcarving blade or toothed saw blade. Such blades create frequent kickback and loss of control.
  

Safety warnings specific for grinding and abrasive cutting-off operations:

• Use only wheel types that are recommended for your power tool and the specific guard designed for the selected wheel. Wheels for which the power tool was not designed cannot be adequately guarded and are unsafe.
  
• The grinding surface of centre depressed wheels must be mounted below the plane of the guard lip. An improperly mounted wheel that projects through the plane of the guard lip cannot be adequately protected.
  
• The guard must be securely attached to the power tool and positioned for maximum safety, so the least amount of wheel is exposed towards the operator. The guard helps to protect the operator from broken wheel fragments, accidental contact with wheel and sparks that could ignite clothing.
  
• Wheels must be used only for recommended applications. For example: do not grind with the side of cut-off wheel. Abrasive cut-off wheels are intended for peripheral grinding, side forces applied to these wheels may cause them to shatter.
  
• Always use undamaged wheel flanges that are of correct size and shape for your selected wheel . Proper wheel flanges support the wheel thus reducing the possibility of wheel breakage. Flanges for cut-off wheels may be different from grinding wheel flanges.
  
• Do not use worn down wheels from larger power tools. Wheel intended for larger power tool is not suitable for the higher speed of a smaller tool and may burst.
  

Additional safety warnings specific for abrasive cutting-off operations:

• Do not "jam" the cut-off wheel or apply excessive pressure. Do not attempt to make an excessive depth of cut. Overstressing the wheel increases the loading and susceptibility to twisting or binding of the wheel in the cut and the possibility of kickback or wheel breakage.
  
• Do not position your body in line with and behind the rotating wheel. When the wheel, at the point of operation, is moving away from your body, the possible kickback may propel the spinning wheel and the power tool directly at you.
  
• When wheel is binding or when interrupting a cut for any reason, switch off the power tool and hold the power tool motionless until the wheel comes to a complete stop. Never attempt to remove the cut-off wheel from the cut while the wheel is in motion otherwise kickback may occur. Investigate and take corrective action to eliminate the cause of wheel binding.
  
• Do not restart the cutting operation in the workpiece. Let the wheel reach full speed and carefully re-enter the cut. The wheel may bind, walk up or kickback if the power tool is restarted in the workpiece.
  
• Support panels or any oversized workpiece to minimize the risk of wheel pinching and kickback. Large workpieces tend to sag under their own weight. Supports must be placed under the workpiece near the line of cut and near the edge of the workpiece on both sides of the wheel.
  
• Use extra caution when making a "pocket cut" into existing walls or other blind areas. The protruding wheel may cut gas or water pipes, electrical wiring or objects that can cause kickback.
  

Additional safety instructions

Personal safety

• Use the tool only when it is in technically faultless condition.
  
• Never tamper with or modify the tool in any way.
  
• Always hold the power tool with both hands on the grips provided. Keep the grips dry, clean and free from oil and grease.
  
• Avoid touching rotating parts – risk of injury! Switch the power tool on only after bringing it into position at the workpiece.
  
• Wear suitable protective glasses, a hard hat, ear protection, protective gloves and light respiratory protection while using the power tool.
  
• Take breaks between working and do physical exercises to improve the blood circulation in your fingers. Exposure to vibration during long periods of work can lead to disorders of the blood vessels and nervous system in the fingers, hands and wrists.
  
• The power tool is not intended for use by debilitated persons who have received no special training. Keep the power tool out of reach of children.
  
• Do not use the product if it starts suddenly or with a jolt. This may indicate a fault in the electronics. Have the product repaired by Hilti Service.
  
• Apply appropriate safety measures at the opposite side of the workpiece in work that involves breaking through. Pieces of debris could drop out and / or fall down and injure other persons.
  
• Slits cut in load-bearing walls of buildings or other structures may influence the statics of the structure, especially when steel reinforcing bars or load-bearing components are cut through. Consult the responsible structural engineer, architect or person in charge of the building project before beginning the work.
  
• Before beginning the work, check the hazard classification of the dust that will be produced. Use an industrial vacuum cleaner with an officially approved protection classification in compliance with locally applicable dust protection regulations.
  
• Use a dust removal system and suitable vacuum cleaner whenever possible. Dust from materials, such as paint containing lead, some wood species, concrete/masonry/stone containing silica, and minerals as well as metal, may be harmful.
  
• Respiratory protection must be worn if the power tool is used without a dust removal system for work that creates dust.
  
• Make sure that the workplace is well ventilated and, where necessary, wear a respirator appropriate for the type of dust generated. Contact with or inhalation of the dust may cause allergic reactions and/or respiratory or other diseases to the operator or bystanders. Certain kinds of dust are classified as carcinogenic such as oak and beech dust, especially in conjunction with additives for wood conditioning (chromate, wood preservative). Material containing asbestos may be handled only by specialists.
  
• To reduce the risk of injury, use only genuine Hilti accessories and accessory tools.
  
• Observe the national health and safety requirements.
  

Electrical safety

• Before beginning work, check the working area (e.g. using a metal detector) to ensure that no concealed electric cables or gas and water pipes are present. External metal parts of the power tool may give you an electric shock if you damage an electric cable accidentally.
  
• Do not touch the supply cord or extension cord if damaged while working. Disconnect the supply cord plug from the power outlet. Check the tool’s supply cord at regular intervals and have it replaced by Hilti Service if damage is found. Check extension cords at regular intervals and replace them if found to be damaged.
  
• Dirty or dusty power tools that have been used frequently for work on conductive materials should be checked at regular intervals at a Hilti Service Center. Dust (especially dust from conductive materials) or dampness adhering to the surface of the tool may, under unfavorable conditions, lead to electric shock.
  

Using and handling power tools with care

• Secure the workpiece. A workpiece clamped in a vice or secured by some other clamping device is more secure than when held only by hand.
  
• Grinding discs must be stored and handled carefully in accordance with the manufacturer’s instructions.
  
• Have the tool checked by Hilti Service after breakage of a disc, if the tool has been dropped or has fallen, or in the event of other mechanical damage.
  

Overview of the product

1. Spindle lockbutton
   
2. Vibration-absorbing side handle
   
3. Air vents
   
4. On/off switch
   
5. Wrench
   
6. Clamping nut
   
7. Kwik lock quick-release clamping nut (optional)
   
8. Abrasive cutting disc / abrasive grinding disc
   
9. Clamping flange with O-ring
   
10. Hood
    
11. Spindle
    
12. Quick locking system
    
13. Guard release button
    
14. Threaded bushing for the side handle
    

Intended use

The product described is a hand-held electric angle grinder. It is designed for cutting and grinding metal and mineral materials without use of water. It may used only for dry cutting / grinding.

The tool may be operated only when connected to a power supply providing a voltage and frequency in compliance with the information given on its type plate.

• The power tool may be used for cutting, slitting and grinding mineral materials only when equipped with the corresponding guard (optional accessory).

• Use of a guide carriage (optional accessory) is mandatory for cutting stone.

• A dust removal system consisting of matched components, i.e. dust removal hood and a suitable Hilti vacuum cleaner, must be used for working on mineral materials such as concrete or stone. These protect the operator and increase the life of the power tool and accessory tools used.

Items supplied

Angle grinder, guard, side handle, clamping flange, clamping nut, wrench and operating instructions.
You can find other system products approved for your product at your local Hilti Center or online at: www.hilti.com

Starting current limitation

The electronic starting current limiter reduces the starting current drawn by the power tool and thus prevents the mains fuse blowing. It also allows the angle grinder to start smoothly, without a jolt.

Constant-speed electronics

Electronic speed control keeps running speed almost constant irrespective of whether the power tool is idling or running under load. Constant running speed helps ensure maximum efficiency.

Active Torque Control (ATC)

The electronics detect potential stalling of the disc and prevent further rotation of the drive spindle by switching off the tool.
If the ACT system has been triggered, restart the tool. Do this by releasing the on/off switch and then pressing it again.

Restart interlock

The angle grinder does not restart by itself when the on/off switch is in the locked position and the power returns after an interruption in the electric supply. The on/off switch must first be released and then pressed again to restart.

Temperature-dependent motor protection

The temperature-dependent motor protection system monitors current input and motor temperature and thus prevents the power tool overheating.
If the motor is overloaded through application of excessive working pressure, the power tool’s performance drops noticeably or it may stall completely. A standstill should be avoided. No specific value can be given for the permissible overloading limit for the power tool as it depends on motor temperature.

DG-EX 125/5" dust hood for grinding (accessory)

The grinding system is suitable only for occasional use with diamond cup wheels for grinding mineral materials.
CAUTION Use of this hood for working on metal is prohibited.

DC-EX 125/5"M dust hood for slitting, with carriage (accessory)

Cutting and slitting work on mineral materials may be carried out only in conjunction with a dust removal hood with guide carriage.
CAUTION Use of this hood for working on metal is prohibited.

DC-EX 125/5"C compact dust hood for cutting (accessory)

DEG 125-D
DEG 125-P

Use the DC-EX 125/5"C compact dust hood when cutting masonry and concrete.
CAUTION Use of this hood for working on metal is prohibited.

Guard with cover plate (accessory)

When grinding with straight grinding discs and cutting with cutting discs in metalworking applications, use the guard with cover plate.

Front cover for the disc guard (accessory)

When grinding with straight grinding discs and cutting with cutting discs in metalworking applications, use the standard guard with front cover.

Angle grinder

	DEG 125-D	DEG 125-P	DEG 150-D	DEG 150-P
Rated power input	1,400 W	1,400 W	1,400 W	1,400 W
Rated speed	11,000 /min	11,000 /min	9,300 /min	9,300 /min
Maximum disc diameter	125 mm	125 mm	150 mm	150 mm
Drive spindle thread	M14	M14	M14	M14
Spindle length	22 mm	22 mm	22 mm	22 mm
Weight in accordance with EPTA procedure 01/2003	2.5 kg	2.5 kg	2.6 kg	2.6 kg

Noise information and vibration values determined in accordance with EN 60745

The sound pressure and vibration values given in these instructions have been measured in accordance with a standardized test and may be used to compare one electric tool with another. They may be used for a preliminary assessment of exposure. The data given represents the main applications of the electric tool. However, if the electric tool is used for different applications, with different accessory tools, or is poorly maintained, the data may vary. This may significantly increase exposure over the total working period. An accurate estimation of exposure should also take into account the times when the power tool is switched off, or when it is running but not actually being used for a job. This may significantly reduce exposure over the total working period. Identify additional safety measures to protect the operator from the effects of noise and/or vibration, for example: maintenance of the electric tool and the accessories, keeping the hands warm, organization of work patterns.
Noise emission values determined in accordance with EN 60745-2-3

Typical A-weighted sound power level (LWA)	100 dB(A)
Typical A-weighted emission sound pressure level (LpA)	89 dB(A)
Uncertainty for the stated sound levels	3 dB

Total vibration (vector sum of three directions), measured in accordance with EN 60745-2-3Other applications, such as cutting, may produce vibration values that deviate from the given values.

	DEG 125-D	DEG 125-P	DEG 150-D	DEG 150-P
Surface grinding with the standard side handle (ah,AG)	11.3 m/s²	11.3 m/s²	8.9 m/s²	8.9 m/s²
Surface grinding with the vibration-absorbing side handle (ah,AG)	7.0 m/s²	7.0 m/s²	7.1 m/s²	7.1 m/s²
Surface grinding with the hoop handle (ah,AG)	9.9 m/s²	9.9 m/s²	8.7 m/s²	8.7 m/s²
Uncertainty (K)	1.5 m/s²	1.5 m/s²	1.5 m/s²	1.5 m/s²

Fitting the side handle

• Screw the side handle into one of the threaded bushings provided.
  

Guard or guard with cover plate

• Observe the instructions for fitting the applicable guard.
  

Fitting the guard or guard with cover plate

1. Fit the guard onto the drive spindle collar so that the two triangular marks on the guard and on the power tool are in alignment.
   
2. Press the guard onto the drive spindle collar.
   
3. Press the guard release button and then rotate the guard until it engages in the desired position.
   
   • The guard release button jumps back.
     

Adjusting the guard

• Press the guard release button and then rotate the guard until it engages in the desired position.
  

Removing the guard or guard with cover plate

1. Press the guard release button and then rotate the guard until the triangular marks on the guard and the power tool are in alignment.
   
2. Lift off the guard.
   

Fitting or removing the front cover

1. Position the front cover with the closed side on the standard guard and push it on until it engages.
   
2. To remove it, release the catch for the front cover and then lift the front cover away from the standard guard.
   

Fitting and removing accessory tools

Fitting an accessory tool

1. Disconnect the supply cord plug from the power outlet.
   
2. Clean the clamping flange and the clamping nut.
   
3. Check that the O-ring is in place in the clamping flange and that it is undamaged.
   Result The O-ring is damaged.
   There is no O-ring in the clamping flange.
   
   • Fit a new clamping flange with O-ring.
     
4. Fit the clamping flange onto the drive spindle.
   
5. Fit the accessory tool.
   

6. Screw on the clamping nut corresponding to the type of accessory tool fitted.
   
7. Press the spindle lockbutton and hold it in this position.
   
8. Use the pin wrench to tighten the clamping nut securely, then release the spindle lockbutton and remove the wrench.
   

Removing the accessory tool

1. Disconnect the supply cord plug from the power outlet.
   

2. Press the spindle lockbutton and hold it in this position.
   
3. Release the clamping nut by gripping it with the pin wrench and turning the nut counterclockwise.
   
4. Release the spindle lockbutton and remove the accessory tool.
   

Fitting an accessory tool secured with a Kwik lock nut

1. Disconnect the supply cord plug from the power outlet.
   
2. Clean the clamping flange and the quick-release clamping nut.
   
3. Check that the O-ring is in place in the clamping flange and that it is undamaged.
   Result The O-ring is damaged.
   There is no O-ring in the clamping flange.
   
   • Fit a new clamping flange with O-ring.
     
4. Fit the clamping flange onto the drive spindle.
   

5. Fit the accessory tool.
   
6. Screw on the Kwik lock nut until it is seated against the accessory tool.
   
   The arrow on the upper surface of the nut must be within the index marks. If the arrow is not within the index marks when the nut is tightened it will be impossible to release the nut by hand. In this case, use the pin wrench to release the Kwik lock nut (do not use a pipe wrench!).
   The name Kwik lock should be visible when the nut is screwed on.
   
7. Press the spindle lockbutton and hold it in this position.
   
8. Turn the accessory tool firmly by hand in a clockwise direction until the Kwik-Lock nut is tightened securely and then release the spindle lockbutton.
   

Removing an accessory tool secured with a Kwik lock nut

1. Disconnect the supply cord plug from the power outlet.
   

2. Press the spindle lockbutton and hold it in this position.
   
3. Release the Kwik lock quick-release nut by turning it counterclockwise by hand.
   
4. If the Kwik lock quick-release nut cannot be released by turning it by hand, use a pin wrench to turn the nut in a counterclockwise direction.
   
5. Release the spindle lockbutton and remove the accessory tool.
   

Rotating the gearing section

1. Disconnect the supply cord plug from the power outlet.
   
2. Clean the tool.
   
3. Remove the side handle from the power tool.
   
4. Release the four screws and then remove the screws and the quick-release device.
   
5. Unscrew and remove the four screws on the gearing section.
   
6. Rotate the gearing section to the desired position without pulling it away from the power tool.
   
7. Secure the gearing section by inserting and tightening the four screws.
   
8. Secure the quick-release device with the four screws so that the gap between the quick-release device and the “inner ring” is concentric.
   
9. Fit the side handle.
   

Grinding

Cutting

• When cutting, apply moderate feed pressure and do not tilt the power tool or the cutting disc (hold at approx. 90° to the surface being cut).
  
  For best results when cutting profiles and square tube, start cutting at the smallest cross section.
  

Rough grinding

• Move the power tool to and fro while maintaining a 5° to 30° angle of attack and applying moderate pressure.
  
  • This will avoid overheating and discoloration of the workpiece and help ensure an even surface finish.
    

Switching on and off

Switching on (switch without lock)

DEG 125-D
DEG 150-D

1. Plug the supply cord into the power outlet.
   
2. Slide the on/off switch forward and then press it as far as it will go.
   

Switching off (switch without lock)

DEG 125-D
DEG 150-D

• Release the on/off switch.
  

Switching on (switch with lock)

DEG 125-P
DEG 150-P

1. Plug the supply cord into the power outlet.
   
2. Slide the on/off switch forward slightly and, while pressing it down, slide it further forward until it locks in position.
   

Switching off (switch with lock)

DEG 125-P
DEG 150-P

• Press the front part of the on/off switch down.
  
  • The lock then releases.
    

Care of the product

DANGER
Electric shock due to breakdown of protective insulation. When working on metal under extreme conditions, conductive dust may accumulate inside the power tool, thereby adversely affecting the protective insulation.

Use a stationary dust extraction system when working under extreme conditions.

Clean the air vents frequently.

Use a ground fault circuit interrupter (PRCD) in the electric power supply line to the power tool.

WARNING
Electrical hazards. Improper repairs to electrical parts may lead to serious injuries.

Electrical parts may be repaired only by trained electrical specialists.

• Never operate the product when the air vents are blocked. Clean the air vents carefully using a dry brush. Do not allow foreign objects to enter the interior of the product.
  

• Keep the product, especially its grip surfaces, clean and free from oil and grease. Do not use cleaning agents containing silicone.
  
• Clean the outer surfaces of the tool with a slightly damp cloth at regular intervals. Do not use a spray, steam pressure cleaning equipment or running water for cleaning.
  
  Frequent work on conductive materials (e.g. metal, carbon fiber) may make shorter maintenance intervals necessary. Take your individual workplace risk assessment into account.
  

Checks after care and maintenance work

• After carrying out care and maintenance, check that all protective and safety devices are fitted and that they function faultlessly.