Westinghouse PT20370 User manual

INSTRUCTION MANUAL
PT20370
7" ANGLE GRINDER
NOTE: Before operating this tool, read this manual
and follow all safety rules and operating instructions.
15A
1,800W
rpm
8,000
120V
60Hz
7
INCHES

GENERAL SAFETY RULES
2
WARNING!
Please read and understand all instructions. Failure to follow all instructions listed
below may result in electric shock, fire and/or serious personal injury.
SAVE THESE INSTRUCTIONS
Work Area
1.Keep your work area clean and well lit. Cluttered benches and dark areas will
invite accidents.
2.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.
3.Keep by standers, children, and visitors away while operating a power tool.
Distraction can cause you to loose control.
Electrical Safety
1. 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.
2. Avoid body contact with grounded surfaces such as pipes, radiators, ranges and
refrigerators. There is an increased risk of electric shock if your body is grounded.
3. Don’t expose power tools to rain or wet conditions. Water entering a power tool
will increase the risk of electric shock.
4. Do not abuse the cord. Never use the cord to carry the tools or pull the plug from
an outlet. Keep the cord away from heat, oil, sharp edges or moving parts. Dama-
ged cords should be replaced immediately by qualified repair personnel. Damaged
cords will increase the risk of electric shock.
5. When operating a power tool outside, use an outdoor heavy duty extension cord
and use in conjunction with a residual current device (RCD).
6. 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.
7.Recommendation for the use of a residual current device with a rated residual
current of 30 mA or less.

GENERAL SAFETY RULES
3
Personal Safety
1. Stay alert, watch what you are doing and use common sense when operating a
power tool. Do not use the tool while tired or under the influence of drugs, alcohol,
or medication. A moment of inattention while operating power tools may result in
serious personal injury.
2. Dress properly. Do not wear loose clothes or jewellery. Contain long hair. Keep
your hair, clothes, and gloves away from moving parts.
3. Avoid accidental starting. Be sure switch is off before plugging in.Carrying tools
with your finger on the switch or plugging in tools that have the switch on may
invite accidents.
4. Remove adjusting keys or wrenches before turning the tool on.A wrench ora key
that is left attached to a rotating part of the tool may result in personal injury.
5. Do not overreach. Keep proper footing and balance at all times.Proper footing and
balance enable better control of the tool in unexpected situations.
6. Dress properly.Do not wear loose clothing or jewelry. Contain long hair. Keep your
hair, clothing, and gloves away from moving parts. Loose clothes, jewelry, or long
hair can be caught in moving parts.
7. Use safety equipments.Always wear eye protection.Dust mask, non-skid safety
shoes, hard hat, or hearing protection must be used for appropriate conditions.
Ordinary eye or sun glasses are NOT suitable for eye protection.
Tool Use and Care
1. Use clamps or other practical way to secure and support the workpiece to a stable
platform. Holding the workpiece by hand or against your body is unstable and may
lead to loss of control.
2. Do not force the tool. Use the correct tool for your application.The correcttool will
do the job better and safer at the rate for which it is designed.
3. Do not use the tool if the switch cannot be turned on or off. Any tool that can not be
controlled with the switch is dangerous and must be repaired before use.
4. Disconnect the plug from the power source before making any adjustment,
changing accessories, or storing the tool.Such preventive safety measures can
reduce the risk of starting the tool accidentally.
5. Store idle tools out of reach of children or other untrained persons.Tools are
dangerous in the hands of untrained users.
6. Maintain tools with care. Keep the cutting tools sharp and clean.Properly maintai-
ned tools with sharp cutting edges are less likely to bind and are easier to control.
7. Check for misalignment or binding of moving parts, breakage of parts and any
other condition that may affect the tools operation. If damaged, have the tool
serviced before using. Many accidents are caused by poorly maintained tools.
8. Some accessories suitable for one toolmay become hazardous when used on
another tool. Please check all accessories to be used are suitable.
Service
1. Tool service must be performed only by qualified repair personnel. Service or
maintenance performed by unqualified personnel could result in a risk of injury.
2. When servicing a tool, use only identical replacement parts.

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 fly
apart and cause injury.
3. Hold tool by insulated gripping surfaces when performing an operation where
the cutting tool may contact hidden wiring or its own cord.
4. Make sure the grinding wheel is not contacting the workpiece before the
switch is turned on.
5. Grinding wheel and guard must be securely attached as described in this
operating manual before connecting the angle grinder to power source.
6. Grinding wheel must be stored in a dry place.
7. Always hold the grinder firmly with two hands while working and at all times
when it is running.
8. Use only quality certified grinding wheels.
9. Keep hands away from rotating parts.
10. Be careful not to damage the spindle, outer flange and inner flange. Damage
to these parts could result in wheel breakage.
11. When starting the tool (install with a new or replacement wheel), hold the tool
in a well protected area and let it run for one minute to check if the wheel is good
or not. Never starting the tool while the operator is standing at in line with the
wheel.
This angle grinder has been designed for professional grinding and cutting
applications. Please refer to the illustration on the inside covering page to familiari-
ze yourself with the major components of this tool before using it.
1.spindle lock button 5.auxiliary handle
2.quick-release lever 6.lock-off catch
3.outer flange 7.trigger switch
4.wheel guard
4
SPECIFIC SAFETY RULES
FEATURES

5
ASSEMBLY
OPERATION
Prior to assembly and adjustment always unplug the tool.
Installing the Grinding Wheel
1. Depress and hold down the spindle lock. To prevent damage to spindle or spindle
lock, always allow motor to come to a complete stop before engaging spindle lock.
2. Remove the outer flange with spanner turning in anti-clockwisedirection. Do not
remove the inner flange.
3. Make sure the slot on theinner flange is engagedwith the square neck of the
spindle.
4. Place the grinding wheel over the spindle with the depressed center against the
inner flange(see Fig.3).
5. Depress and hold down the spindle lock again,mountthe outer flange and securely
tighten it with spanner provided clockwise.Do not overtighten it.
Mounting theAuxiliary
HandleThe tool has three screwed holes on top, left and right side of the gear housing.
Operators can choose any one of them to mount the auxiliary handle depending on
specific working condition and their ownhabit.
Adjusting the Wheel Guard
This tool comes with a wheel guard. The guard must be fitted before using the tool.Lift
the quick release guard lever to loosen the guard.
1. Pull the quick release lever toward outside so as to enlarge the circular collar of
wheel guard.
2. Align the protruding part inside the circular collar with the notch on the front cap.
Mount the collar fully onto the front cap.
3. If the collar is too small in circumference to be fitted in, the nut on the quick release
lever can be adjusted so as to enlarge the collar.
4. Turn the wheel guard to a desired angle after the collar is fully inserted.Pull back the
quick release lever to lock the guard with the front cap.
5. Make sure the guard is firmly secured in place. If the guard is still loose after pulling
back the quick release lever, pull up the lever, properly adjust the nut and pull back
the lever again.
This heavy duty grinder is designed for the following purposes:
1. Removal of casting burrs and finishing on various types of steel, bronze, aluminum
materials and castings.
2. Beveling and finishing weld seams
3. Grinding of welded sections cut by means of welding.
4. Grinding of synthetic resin bricks, marbles etc.
5. Cutting thin wall tubes and small size metal materials.

6
OPERATION
Caution! Never cover air vents. They must always be open for proper motor cooling.
To start your grinder:
 Plug the cordset into a power socket;
 Push the Lock-off catch on the trigger switch forward;
 Pull on the trigger switch.
To stop your grinder:
 Release the on/off switch.
For Proper Operations
1. Before starting the grinder, put on safety glasses and make sure thatthe grinding
wheel, guard and the tool are in good condition and correctly fitted.
2. Always hold the tool firmly with one hand on the rear handle and the other on the
side handle.
3. Turn the angle grinder on and then apply the grinding wheel to the workpiece.
4. In general, keep the edge of the wheel at an angle of about 30°for roughing and
about 15 for finishing.
5. Move the grinder back and forth or up and down over the work area.
6. Use just enough pressure to keep the grinder from chattering or bouncing.
7. Avoid overloading the tool for a long time, heavy pressure will decrease its speed
and put a strain on the motor.
8. Lift the grinder away from the workpiece before turning your grinder off.
WARNING! Never use your grinder without wearing eye protection. Following this
rule will reduce the risk of serious personal injury.
DANGER!
1.Never attach a wood cutting or carving blade of any type to this angle grinder.
2.Never use your grinder with guard removed.
3.Failure to follow this rule could result in serious personal injury.
WARNING! If any of the following events occurs during normal operation, the power
supply should be shut off immediately and then the tool should be inspected
thoroughly and repaired by a qualified person and repaired it if necessary:
1.The rotating parts get stuck or speed drops abnormally low.
2.The tool shakes abnormally and accompanied by some unusual noise.
3.The motor housing gets abnormally hot.
4.Heavy sparks occurring around the motor area.

7
MAINTENANCE
WARNING!
Maintenance and repair work should only be done by a qualified service technician.
When servicing a tool, it’s recommended to use only spare parts provided by the
manufacturer of the tool. Preventive maintenance performed by unauthorized
personnel may result in misplacing of internal wires and components which could
cause serious hazard.
CAUTION!
Always be sure that the tool is switched off and unplugged before attempting to
perform inspection or maintenance. Regularly clean the tool’s air vents with
compressed dry air. Do not attempt to clean by inserting pointed objects through
openings.
CAUTION!
Certain cleaning agents and solvents may damage plastic parts. Some of these are:
gasoline, carbon tetrachloride, chlorinated cleaning solvents, ammonia and house-
hold detergents that contain ammonia. To ensure safe use and maximize service
life of your tool, following instructions should be observed:
1. Regularly inspect the grinding wheel----ensure that the grinding wheel is free of
cracks and surface defects. Replace the grinding wheel when it has worn out.
2. Periodically check the mounting screws—regularly inspect all mounting screws
and ensure that they are properly tightened.
3. Regularly clean the air vents of the tool.
4. Check and replace carbon brushes when necessary. When it’s necessary, peel
off the labels on both sides of the tool.
Remove the carbon brush caps with screwdriver. Pull out the carbon brushes for
inspection. If the brushes are worn out, they should be replaced with a new pair of
brushes. Note that the brushes must be replaced in pair. Make sure the brush can
be slided freely inside the brush holder. Put back the brush caps and tighten them
with screws. Be careful not to overtighten the screws.

8
SPECIFICATIONS
ACCESSORIES
 spanner-------------------------------------1pc
 side handle---------------------------------1pc
 carbon brush ------------------------------1pair
 instruction manual------------------------1pc
Model: PT20370
Voltage: 120V～60Hz
Rated Power: 1800 W
Wheel Size: 180mm
No Load Speed: 8000 RPM

PART LIST
SAVE THESE INSTRUCTIONS FOR REFERENCE
9
Pos. Part No. Part Name Pos. Part No. Part Name
1 Z130002 Outer Flange 28 K75000H Pinion
2 F103006 Grinding Wheel 29 E136201 Bearing 6201
3 Z120002 Inner Flange 30 I00000H Bearing Retaining Plate
4 C310804 Screw M8 31 GQ72002 Rotor
5 C40000U Washer 32 E110629 Bearing 629
6 H7J1001 Quick Release Guard 33 H001005 Bearing Sleeve
7 I71000C Wheel Guard 34 H72100D Baffle Ring
8 J71000B Spindle 35 C514272 Self-tapping Screw 4.2*72 (1)
9 C814013 Woodruff Key 36 GQ71002 Stator
10 C120416 Philips Pan Head Screw M5X16 (4) 37 G370001 Lug (1)
11 C410513 Spring Washer 5 (4) 38 Z600004 Heat Shrinkable Tube
12 C430501 Flat Washer (8) 39 I740003 Magnesium Alloy Sleeve
13 M73000C Front Cap 40 C534214 Self-tapping Screw 4.2X14 (4)
14 E136203 Bearing 6203 41 H7C100C Carbon Brush Cap (Left)
15 I00000H Bearing Retaining Plate 42 H71100D Motor Housing
16 C410411 Spring Washer 4 (7) 43 G407130 Carbon Brush (2)
17 C610412 Philips Pan Head Screw M4X12 (7) 44 G53000K Brush Holder (2)
18 K75000G Bevel Gear 45 H7C100C Carbon Brush Cap (Right)
19 C0105102 Open Circlip 46 Z020007 Coil Spring (2)
20 E201210 Needle Gear 47 B67000A Nameplate
21 C010510 Open Circlip 48 C534216 Self-tapping Screw (5)
22 C524825 Philips Pan Head Screw 4.8*28 (1) 49 H77100C Left Handle
23 Z000003 Spring 50 G210004 Cable&Plug
24 H7B100B Spindle Lock Button 51 H000001 Cable Clamp
25 H7A1005 Auxiliary Handle 52 H00200D Cable Sleeve
26 M71000D Gear Housing 53 H78100C Right Handle
27 C320001 Locknut M8 (Black) 54 G12000Q Switch
Note:The expousure drawing and part list are subject to change without prior notice.

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