G18ST - Grinder HITACHI - Free user manual and instructions

USER MANUAL G18ST HITACHI

SAFETY INSTRUCTIONS AND INSTRUCTION MANUAL

Read and understand all of the safety precautions, warnings and operating instructions in the Instruction Manual before operating or maintaining this power tool. Most accidents that result from power tool operation and maintenance are caused by the failure to observe basic safety rules or precautions. An accident can often be avoided by recognizing a potentially hazardous situation before it occurs, and by observing appropriate safety procedures. Basic safety precautions are outlined in the “SAFETY” section of this Instruction Manual and in the sections which contain the operation and maintenance instructions. Hazards that must be avoided to prevent bodily injury or machine damage are identifi ed by WARNINGS on the power tool and in this Instruction Manual. NEVER use this power tool in a manner that has not been specifi cally recommended by HITACHI.

MEANINGS OF SIGNAL WORDS

WARNING indicates a potentially hazardous situations which, if ignored, could result in death or serious injury. CAUTION indicates a potentially hazardous situations which, if not avoided, may result in minor or moderate injury, or may cause machine damage. NOTE emphasizes essential information. SAFETY

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, fi re 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.

a) Keep work area clean and well lit. Cluttered or dark areas invite accidents. b) Do not operate power tools in explosive atmospheres, such as in the presence of fl ammable liquids, gases or dust. Power tools create sparks which may ignite the dust or fumes. c) Keep children and bystanders away while operating a power tool. Distractions can cause you to lose control.

2) Electrical safety

a) 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. b) 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. c) Do not expose power tools to rain or wet conditions. Water entering a power tool will increase the risk of electric shock. d) 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. e) 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. f) 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. BookG18STUS.indb4BookG18STUS.indb4 2014/12/1111:41:272014/12/1111:41:27English

a) 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 infl uence of drugs, alcohol or medication. A moment of inattention while operating power tools may result in serious personal injury. b) 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. c) 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. d) 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. e) Do not overreach. Keep proper footing and balance at all times. This enables better control of the power tool in unexpected situations. f) 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. g) 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.

4) Power tool use and care

a) 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. b) 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. c) 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. d) 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. e) 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. f) Keep cutting tools sharp and clean. Properly maintained cutting tools with sharp cutting edges are less likely to bind and are easier to control. g) 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.

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

OPERATIONS a) 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, fi re and/or serious injury. b) 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. c) Do not use accessories which are not specifi cally designed and recommended by the tool manufacturer. Just because the accessory can be attached to your power tool, it does not assure safe operation. d) The rated speed of the accessory must be at least equal to the maximum speed marked on the power tool. BookG18STUS.indb5BookG18STUS.indb5 2014/12/1111:41:272014/12/1111:41:27English

Accessories running faster than their rated speed can break and fl y apart. e) 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. f) Threaded mounting of accessories must match the grinder spindle thread. For accessories mounted by flanges, the arbour hole of the accessory must fi t the locating diameter of the fl ange. 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. g) 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. h) 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.

i) 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 fl y away and cause injury beyond immediate area of operation. j) 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. k) 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. l) 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. m) 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. n) Regularly clean the power tool’s air vents. The motor’s fan will draw the dust inside the hous- ing and excessive accumulation of powdered metal may cause electrical hazards. o) Do not operate the power tool near fl ammable materials. Sparks could ignite these materials. p) Do not use accessories that require liquid coolants. Using water or other liquid coolants may result in electrocution or shock.

KICKBACK AND RELATED WARNINGS

Kickback 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. a) 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 kick- back forces, if proper precautions are taken. b) Never place your hand near the rotating accessory. Accessory may kickback over your hand. c) 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. BookG18STUS.indb6BookG18STUS.indb6 2014/12/1111:41:272014/12/1111:41:27English

d) 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. e) Do not attach a saw chain woodcarving blade or toothed saw blade. Such blades create frequent kickback and loss of control.

OPERATIONS a) 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. b) The grinding surface of center 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. c) 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 operator from broken wheel fragments, accidental contact with wheel and sparks that could ignite clothing. d) 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. e) Always use undamaged wheel fl anges 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 fl anges. f) 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.

OPERATIONS a) 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. b) 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. c) 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. d) Do not restart the cutting operation in the workpiece. Let the wheel reach full speed and carefully reenter the cut. The wheel may bind, walk up or kickback if the power tool is restarted in the workpiece. e) 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. f) 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.

GENERAL SAFETY INSTRUCTIONS FOR

GRINDERS – Check that speed marked on the wheel is equal to or greater than the rated speed of the grinder; – Ensure that the wheel dimensions are compatible with the grinder; – Abrasive wheels shall be stored and handled with care in accordance with manufacturer’s instructions; – Inspect the grinding wheel before use, do not use chipped, cracked or otherwise defective products; – Ensure that mounted wheels and points are fi tted in accordance with the manufacturer’s instructions; – Ensure that blotters are used when they are provided with the bonded abrasive product and when they are required; – Ensure that the abrasive product is correctly mounted and tightened before use and run the tool at no-load for 30 s in a safe position, stop immediately if there is considerable vibration or if other defects are detected. If this condition occurs, check the machine to determine the cause; – If a guard is equipped with the tool never use the tool without such a guard; – Do not use separate reducing bushings or adapters to adapt large hole abrasive wheels; – For tools intended to be fi tted with threaded hole wheel, ensure that the thread in the wheel is long enough to accept the spindle length; BookG18STUS.indb7BookG18STUS.indb7 2014/12/1111:41:272014/12/1111:41:27English

– Secure the workpiece and check that the workpiece is properly supported. A workpiece clamped with clamping devices or in a vice is held more securely than by hand; – Check that the work piece is properly supported; – Do not use cutting off wheel for side grinding; – Ensure that sparks resulting from use do not create a hazard e.g. do not hit persons, or ignite fl ammable substances; – Ensure that ventilation openings are kept clear when working in dusty conditions, if it should become necessary to clear dust, first disconnect the tool from the mains supply (use non metallic objects) and avoid damaging internal parts; – Always use eye and ear protection. Other personal protective equipment such as dust mask, gloves, helmet and apron should be worn; – Pay attention to the wheel that continues to rotate after the tool is switched off .

SPECIFIC SAFETY RULES AND SYMBOLS

1. ALWAYS use proper guard with grinding wheel.

A guard protects operator from broken wheel fragments.

2. Accessories must be rated for at least the speed

recommended on the tool warning label. Wheels and other accessories running over rated speed can fl y apart and cause injury.

3. ALWAYS wear ear protectors when using the

tool for extended periods. Prolonged exposure to high intensity noise can cause hearing loss.

4. Use only a depressed center wheel with a

rated capacity which is GREATER than 6,600/ min. Using any wheel a rated capacity LESS than 6,600/min and/or an incorrect sized wheel (see SPECIFICATIONS at page 10) may result in wheel breakage, flying wheel fragments, and resulting in death or serious injury.

5. NEVER touch moving parts.

NEVER place your hands, fingers or other body parts near the tool’s moving parts.

6. NEVER operate without all guards in place.

NEVER operate this tool without all guards or safety features in place and in proper working order. If maintenance or servicing requires the removal of a guard or safety feature, be sure to replace the guard or safety feature before resuming operation of the tool.

Don’t force small tool or attachment to do the job of a heavy-duty tool. Don’t use tool for purpose not intended —for example— don’t use circular saw for cutting tree limbs or logs.

8. NEVER use a power tool for applications other

than those specifi ed. NEVER use a power tool for applications other than those specifi ed in the Instruction Manual.

9. Handle tool correctly.

Operate the tool according to the instructions provided herein. Do not drop or throw the tool. NEVER allow the tool to be operated by children, individuals unfamiliar with its operation or unauthorized personnel.

10. Keep all screws, bolts and covers tightly in

place. Keep all screws, bolts, and plates tightly mounted. Check their condition periodically.

11. Do not use power tools if the plastic housing or

handle is cracked. Cracks in the tool’s housing or handle can lead to electric shock. Such tools should not be used until repaired.

12. Blades and accessories must be securely

mounted to the tool. Prevent potential injuries to yourself or others. Blades, cutting implements and accessories which have been mounted to the tool should be secure and tight.

13. Keep motor air vent clean.

The tool’s motor air vent must be kept clean so that air can freely fl ow at all times. Check for dust build-up frequently.

14. Operate power tools at the rated voltage.

Operate the power tool at voltages specified on its nameplate. If using the power tool at a higher voltage than the rated voltage, it will result in abnormally fast motor revolution and may damage the unit and the motor may burn out.

15. NEVER use a tool which is defective or operating

abnormally. If the tool appears to be operating unusually, making strange noises, or otherwise appears defective, stop using it immediately and arrange for repairs by a Hitachi authorized service center.

16. NEVER leave tool running unattended. Turn

power off . Don’t leave tool until it comes to a complete stop.

17. Carefully handle power tools.

Should a power tool be dropped or struck against hard materials inadvertently, it may be deformed, cracked, or damaged.

18. Do not wipe plastic parts with solvent.

Solvents such as gasoline, thinner benzine, carbon tetrachloride, and alcohol may damage and crack plastic parts. Do not wipe them with such solvents. Wipe plastic parts with a soft cloth lightly dampened with soapy water and dry thoroughly. BookG18STUS.indb8BookG18STUS.indb8 2014/12/1111:41:272014/12/1111:41:27English

19. NEVER use a depressed center wheel which is cracked

generated by the grinder can cause explosion, such as where fl ammable materials or gases are present.

21. NEVER push in the push button while the spindle is

22. ALWAYS wear eye protection that meets the

requirement of the latest revision of ANSI Standard Z87.1.

23. ALWAYS wear a mask or respirator to protect

yourself from dust or potentially harmful particles generated during the grinding operation.

24. ALWAYS fi rmly grip the body handle and side handle

while operating the grinder.

25. ALWAYS have a trial run before grinding commence.

(see “Test the grinder before using” on page 11).

26. ALWAYS follow the instructions contained in this

manual when replacing the depressed center wheel.

27. ALWAYS be careful with buried object such as an

underground wiring. Touching these active wiring or electric cable with this tool, you may receive an electric shock. Confi rm if there are any buried object such as electric cable within the wall, fl oor or ceiling where you are going to operate here after.

OPERATION To ensure safer operation of this power tool, HITACHI has adopted a double insulation design. “Double insulation” means that two physically separated insulation systems have been used to insulate the electrically conductive materials connected to the power supply from the outer frame handled by the operator. Therefore, either the symbol “ ” or the words “Double insulation” appear on the power tool or on the nameplate. Although this system has no external grounding, you must still follow the normal electrical safety precautions given in this Instruction Manual, including not using the power tool in wet environments. To keep the double insulation system effective, follow these precautions:

Only HITACHI AUTHORIZED SERVICE CENTER should disassemble or assemble this power tool, and only genuine HITACHI replacement parts should be installed.

Clean the exterior of the power tool only with a soft cloth moistened with soapy water, and dry thoroughly. Never use solvents, gasoline or thinners on plastic components; otherwise the plastic may dissolve.

SAVE THESE INSTRUCTIONS

Fig. 1 Gear cover Push button Switch Housing Brush cover Packing gland Wheel guard Handle Side handle Depressed center wheel FUNCTIONAL DESCRIPTION NOTE The information contained in this Instruction Manual is designed to assist you in the safe operation and maintenance of the power tool. NEVER operate, or attempt any maintenance on the tool unless you have first read and understood all safety instructions contained in this manual. Some illustrations in this Instruction Manual may show details or attachments that diff er from those on your own power tool.

Removal of casting fi n and fi nishing of various type of steel, bronze and aluminum materials and castings.

Grinding of welded sections or sections cut by means of an acetylene torch.

Grinding of synthetic resins, slate, brick, marble. WARNING To avoid the risk of serious injury, NEVER use this grinder with cup wheels and/or saw blades.

Ensure that the power source to be utilized conforms to the power source requirements specified on the product nameplate.

Ensure that the switch is in the OFF position. If the plug is connected to a receptacle while the switch is in the ON position, the power tool will start operating immediately and can cause serious injury.

When the work area is far away from the power source, use an extension cord of suffi cient thickness and rated capacity. The extension cord should be kept as short as practicable. WARNING Damaged cord must be replaced or repaired.

4. Check the receptacle

If the receptacle only loosely accepts the plug, the receptacle must be repaired. Contact a licensed electrician to make appropriate repairs. If such a faulty receptacle is used, it may cause overheating, resulting in a serious hazard.

5. Check your work environment

Ensure the following before operation;

When grinding thin steel sheet it may cause a high booming noise. To avoid such noise, place a rubber mat under the workpiece.

Clear the area of children or unauthorized personnel.

6. Mounting the wheel guard

Be sure to mount the wheel guard at an angle that will protect the operator’s body from injury by a broken wheel piece. [Installing and adjusting the wheel guard]

Slightly loosen the screw on the wheel guard.

Install the wheel-guard-locating pin in line with the across flats of the packing gland, turn it to the angle suitable for operation, and make adjustment.

After the adjustment, ensure that the screw is securely tightened on the wheel guard in order to fi x it completely. Fig. 2 WARNING If the wheel guard is not attached properly, a broken wheel may result in and cause death or serious injury.

7. Thoroughly check that the depressed center wheel is

free of cracks, splits and other abnormalities before mounting. Make sure it is firmly clamped and has been properly mounted. Refer to page 12 of this manual for Depressed Center Wheel Assembly and Disassembly

8. Test the grinder before using.

Before actually beginning the grinding work, test the grinder by first clearing the area of all other personnel. Make sure the wheel guard is in place and that you are wearing eye protection. Turn the grinder “on”, and make sure the grinder runs smoothly and shows no abnormalities. Duration of the trial run is as follows: When depressed center wheel is replaced .............................................. 3 minutes or more When starting daily work ................................................1 minute or more BookG18STUS.indb11BookG18STUS.indb11 2014/12/1111:41:272014/12/1111:41:27English

9. Use only properly rated depressed center wheels.

Use only depressed center wheels rated at 6,600/min or more. Using a depressed center wheel rated less can lead to wheel disintegration during operation and cause serious bodily injury.

10. Check the push button.

Make sure that the push button is disengaged by pushing push button two or three times before turning on the grinder. (Fig. 5) GRINDER OPERATION

1. Hold the grinder fi rmly by its handle and side handle

(Fig. 1) The grinder produces a counterforce which must be controlled by fi rmly holding onto the grinder.

2. Turn the grinder “on” (Fig. 3)

While holding the grinder firmly, use one finger to switch to the “on” position. Switch ON: Push the locking button forward and then press the switch lever.

• For continuous use, press the switch lever. The switch lever is locked by pushing the locking button forward once again. (*For the switch with Lock-On mechanism.) Switch OFF: Press and release the switch lever. Fig. 3

3. Use light grinding pressure.

There is no need to press hard when grinding. Usually the grinder’s own weight is suffi cient to allow the required light contact with the surface to be ground. WARNING Do not press the grinder forcibly against the surface to be ground. Heavy pressure can result in wheel breakage and serious injury. It can also damage the surface being ground or damage the grinder’s motor.

4. Use proper grinding angle.

Grind only with the wheel’s edge by lifting the grinder 15° to 30°, as shown in Fig. 4. CAUTION Do not use the entire surface of the depressed center wheel. Use only the edge of the depressed center wheel.

5. Move the grinder in the proper direction.

When using a new depressed center wheel in direction A (Fig. 4), the wheel edge may cut into the workpiece. In this case, grind in direction B (Fig. 4). Once the wheel edge is worn, the workpiece can be ground in both directions. Fig. 4 NOTE The wheel provided (resinoid wheel) is rated as Class A grain and # 24 grain size. It is most suitable for heavy grinding of steel and other types of materials.

6. Adjust operation to desired fi nish.

For a fi ne fi nish, decrease pressure by lifting slightly. Grind slowly and at the appropriate speed. CAUTION The revolving depressed center wheel will create air turbulence. Do no lay the grinder down in areas of dust or dirt until it has come to a complete stop.

DEPRESSED CENTER WHEEL ASSEMBLY

AND DISASSEMBLY WARNING Never attempt to assemble or disassemble the depressed center wheel, unless the power switch is in the “OFF” position and the electrical cord has been disconnected from the receptacle.

(1) Turn the disc grinder upsidedown so that the spindle is facing upward. (2) Align the oval-shaped indentation of the wheel washer with the notched part of the spindle, then attach them. (3) Fit the protuberance of the depressed center wheel onto the wheel washer. (4) Screw the wheel nut onto the spindle. Switch lever Locking button A B 15° – 30° BookG18STUS.indb12BookG18STUS.indb12 2014/12/1111:41:282014/12/1111:41:28English

(5) While pushing the push button with one hand, lock the spindle by turning the depressed center wheel slowly with the other hand. Tighten the wheel nut by using the supplied wrench as shown in Fig. 5. (6) Wheel size must match guard size; i.e., a new 7" wheel may not be used with a 9" guard. CAUTION Tighten the wheel nut securely and confi rm that the depressed center wheel does not wobble.

To remove the depressed center wheel, simply reverse the above-mentioned procedure.

Be sure to switch power OFF and disconnect the plug from the receptacle during maintenance and inspection.

Using cracked, deformed or damaged wheels can lead to wheel breakage and resulting serious injury.

1. Replacing the depressed center wheel

Replace the depressed center wheel when it has been worn out to about 2-3/8" (60mm) in external diameter. Confi rm that there is no crack or any damage to the depressed center wheel. If there is a crack or a transformation in the wheel, replace it immediately.

2. Inspecting the screws

Regularly inspect all screws and ensure that they are fully tightened. Should any of the screws be loosened, retighten them immediately. WARNING Using this grinder with loosened screws is extremely dangerous.

3. Confi rm that there is no damage in the wheel guard,

the electrical cord and the housing, etc. Check that the on/off switch operates normally.

4. Inspecting the carbon brushes (Fig. 6)

The motor employs carbon brushes which are consumable parts. Replace the carbon brush with a new one when it becomes worn to its wear limit. Always keep carbon brushes clean and ensure that they slide freely within the brush holders. Fig. 6 Fig. 7 Carbon Brush Spring Brush Holder Fig. 5 Wheel nut Wheel guard Push button Wrench Wheel washer Spindle Depressed center wheel Tighten

CAUTION Using this grinder with a carbon brush which is worn in excess of the wear limit will damage the motor. NOTE Use HITACHI carbon brush No. 59 indicated in Fig. 6.

5. Replacing carbon brushes:

<Disassembly> (1) Loosen the D4 tapping screw retaining the brush cover and remove the brush cover. (2) Use the auxiliary hexagonal wrench or small screwdriver to pull up the edge of the spring that is holding down the carbon brush. Remove the edge of the spring toward the outside of the brush holder. (3) Remove the end of the pig-tail on the carbon brush from the terminal section of brush holder and then remove the carbon brush form the brush holder. <Assembly> (1) Insert the end of the pig-tail of the carbon brush in the terminal section of brush holder. (2) Insert the carbon brush in the brush holder. (3) Use the auxiliary hexagonal wrench or small screwdriver to return the edge of the spring to the head of the carbon brush. (4) Mount the tail cover and tighten the D4 tapping screw. ACCESSORIES WARNING Never use any accessories other than those mentioned below. The use of any accessories other than those mentioned below or attachments not intended for use such as cup wheel, cut-off wheel or saw blade is dangerous and may cause personal injury or property damage. NOTE Accessories are subject to change without any obligation on the part of the HITACHI. STANDARD ACCESSORIES

Hexagonal bar wrench (Code No. 872422)...............1

1/4" (6 mm) thickness

1/4" (6 mm) thickness

7/8" (22.23 mm) hole dia. (Code No. 701090) NOTE Specifications are subject to change without any obligation on the part of the HITACHI. 6 Service and repairs All quality power tools will eventually require servicing or replacement of parts because of wear from normal use. To assure that only authorized replacement parts will be used, all service and repairs must be performed by a HITACHI AUTHORIZED SERVICE CENTER, ONLY. 7 Service parts list CAUTION Repair, modification and inspection of Hitachi Power Tools must be carried out by a Hitachi Authorized Service Center. This Parts List will be helpful if presented with the tool to the Hitachi Authorized Service Center when requesting repair or other maintenance. In the operation and maintenance of power tools, the safety regulations and standards prescribed in each country must be observed. MODIFICATIONS Hitachi Power Tools are constantly being improved and modified to incorporate the latest technological advancements. Accordingly, some parts may be changed without prior notice. BookG18STUS.indb14BookG18STUS.indb14 2014/12/1111:41:282014/12/1111:41:2815 Français

4 GEAR COVER ASS'Y 1

Some dust created by power sanding, sawing, grinding, drilling, and other construction activities contains chemicals known to the State of California to cause cancer, birth defects or other reproductive harm. Some examples of these chemicals are:

Lead from lead-based paints,

Crystalline silica from bricks and cement and other masonry products, and

Arsenic and chromium from chemically-treated lumber. Your risk from these exposures varies, depending on how often you do this type of work. To reduce your exposure to these chemicals: work in a well ventilated area, and work with approved safety equipment, such as those dust masks that are specially designed to fi lter out microscopic particles.