Westinghouse PT10794 User manual

INSTRUCTION MANUAL
PT10794
1/3 SHEET FINISHING SANDER
150
Watts 1.3
Amp
12,000
opm C US
120v
60Hz
Note: Before operating this tool, read this manual
and follow safety rules and operating instrucctions.

TABLE OF CONTENTS
2
Product specifications ………….……………………………………………………. 1
Table of contents ……………………………………………………………………... 2
General safety warnings …………………………………………………………….. 3–4
Eye, ear & lung protection …………………………………………………………… 3–4
Electrical safety ………………………………………………………………………. 4
Power tool safety ……………………………………………………………………... 5–6
Work area ………………………………………………………………….………….. 5
Electrical safety ………………………………………………………………………. 5
Personal safety ……………………………………………………………………….. 6–7
Power tool use and care.…………………………………………………………….. 7
Service ………………………………………………………………………………… 7
Specific safety rules ………………………………………………………………….. 8
Extension cord safety ………………………………………………………….…….. 9
Symbols ……………………………………………………………………………….. 10
Know your sander …………………………........................................................... 11
Available accessories ………………………………………………………………... 11
Contents ………………………………………………………………………………. 12
Assembly and operating …………………………………………………………….. 13–17
Installing a sandpaper ……………………………………………………………...... 13
Punching holes in sandpaper ……………………………………………………….. 13
ON/OFF trigger switch ……………………………………………………………….. 14
Lock-on button ……………………………………………………………………….. 14
Installing the vacuum adapter ………………………………………………………. 14
Sandpaper selection …………………………………………………………………. 15–16
Sanding ……………………………………………………………………………….. 16–17
Maintenance ………………………………………………………………………….. 18
Exploded view ………………………………………………………………………... 19
Parts listing ……………………………………………………………………………. 20

GENERAL SAFETY WARNINGS
EYE, EAR & LUNG PROTECTION
3
WARNING: Before using this tool or any of its accessories, read this
manual and follow all Safety Rules and Operating Instructions. The important precautions,
safeguards and instructions appearing in this manual are not meant to cover all possible
situations. It must be understood that common sense and caution are factors which
cannot be built into the product.
This instruction manual includes the following:
• General Safety Rules
• Specific Safety Rules and Symbols
• Functional Description
• Assembly
• Operation
• Maintenance
• Accessories
ALWAYS WEAR EYE PROTECTION THAT CONFORMS WITH CSA
REQUIREMENTS or ANSI SAFETY STANDARD Z87.1
FLYING DEBRIS can cause permanent eye damage. Prescription
eyeglasses ARE NOT a replacement for proper eye protection.
WARNING: Non-compliant eyewear can cause serious injury if
broken during the operation of a power tool.
WARNING: Use hearing protection, particularly during extended
periods of operation of the tool, or if the operation is noisy.

GENERAL SAFETY WARNINGS
ELECTRICAL SAFETY
4
WEAR A DUST MASK THAT IS DESIGNED TO BE USED WHEN
OPERATING A POWER TOOL IN A DUSTY ENVIRONMENT.
WARNING: Dust that is created by power sanding, sawing, grinding,
drilling, and other construction activities may contain chemicals that are
known to cause cancer, birth defects, or other genetic abnormalities. These
chemicals include:
Lead from lead-based paints
Crystalline silica from bricks, cement, and other masonry products
Arsenic and chromium from chemically treated lumber
The level of risk from exposure to these chemicals varies, according to how
often this type of work is performed. In order to reduce exposure to these
chemicals, work in a well-ventilated area, and use approved safety
equipment, such as a dust mask that is specifically designed to filter out
microscopic particles.
WARNING: To avoid electrical hazards, fire hazards or damage to the
tool, use proper circuit protection.
This tool is wired at the factory for 120V AC operation. It must be connected
to a 120V AC, 15 AMP circuit that is protected by a time-delayed fuse or
circuit breaker. To avoid shock or fire, replace power cord immediately if
it is worn, cut or damaged in any way.

POWER TOOL SAFETY
5
WARNING: Read all safety warnings
and 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.
Workarea safety
Keep workarea 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.

6
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 a ground fault circuit interrupter
(GFCI) 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 energizing power tools
that have the switch on invites accidents.

POWER TOOL SAFETY
SAVE THESE INSTRUCTIONS FOR REFERENCE
7
PERSONAL SAFETY – cont’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.
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. Checkfor
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 accordancewith these
instructions, taking into account the
working conditions and the workto 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.

SPECIFIC SAFETY RULES
SAVE THESE INSTRUCTIONS FOR REFERENCE
8
WARNING: Know your sander. Do
not plug in the sander until you have
read and understand this Instruction
Manual. Learn the tool’s applications
and limitations, as well as the specific
potential hazards related to this tool.
Following this rule will reduce the risk of
electric shock, fire, or serious injury.
Always wear eye protection.
Any power tool can throw
foreign objects into your eyes
and cause permanent eye
damage. ALWAYS wear safety goggles
(not glasses) that comply with ANSI safety
standard Z87.1. Everyday glasses have
only impact resistant lenses. They ARE
NOT safety glasses.
WARNING: Glasses or goggles
not in compliance with ANSI Z87.1
could cause serious injury when they
break.
WARNING: Always use a dust
mask when sanding.
WARNING: Always use hearing
protection when sanding, particularly
during extended periods of operation.
WARNING: Always unplug the
tool from the power source before
changing the sanding disc or buffing
pad and when cleaning the tool.
Do not wear gloves, neckties or loose
clothing.
Secure the workpiece. Use clamps or a
vice to hold the work when practical. It is
safer than using your hand and it frees
both hands to operate the tool.
Do not sand material too small to be
securely held.
Make sure there are no nails or foreign
objects in the part of the workpiece to be
sanded.
Always keep hands out of the path of the
sanding pad. Avoid awkward hand
positions where a sudden slip could cause
your hand to move into the path of the
sanding pad.
To avoid injury from accidental starting,
always remove the plug from the power
source before installing or removing
sandpaper or the dust duct bag.

EXTENSION CORD SAFETY
9
WARNING: Keep the extension
cord clear of the working area. Position
the cord so it will not get caught on the
workpiece, tools or any other obstructions
while you are working with the power tool.
Make sure any extension cord used with
this tool is in good condition. When using
an extension cord, be sure to use one of
heavy enough gauge to carry the current
the tool will draw. An undersized cord will
cause a drop in line voltage resulting in
loss of power and overheating.
The table at right shows the correct size to
use according to cord length and
nameplate ampere rating. If in doubt, use
the next heavier gauge. The smaller the
gauge number the heavier the cord.
Be sure your extension cord is properly
wired and in good condition. Always
replace a damaged extension cord or have
it repaired by a qualified electrician before
using it. Protect your extension cord from
sharp objects, excessive heat and damp or
wet areas.
Use a separate electrical circuit for your
power tools. This circuit must not be less
than 14 gauge wire and should be
protected with either a 15 AMP time
delayed fuse or circuit breaker. Before
connecting the power tool to the power
source, make sure the switch is in the OFF
position and the power source is the same
as indicated on the nameplate. Running at
lower voltage will damage the motor.
MINIMUM GAUGE(AWG)
EXTENSION CORDS (120V use only)
Amperage
rating Total length
More
than
Not
more
than
25'
(7.5 m)
50'
(15 m)
100'
(30 m)
150'
(45 m)
0
6
18
16
16
14
6
10
18
16
14
12
10
12
16
16
14
12
12
16
14
12
Not Applicable

SYMBOLS
10
V
Volts
A
Amperes
Hz
Hertz
W
Watts
kW
Kilowatts
Microfarads
L
Liters
kg
Kilograms
H
Hours
N/cm2Newtons per square
centimeter
Pa
Pascals
OPM
Oscillations per minute
Min
Minutes
S
Seconds
or a.c. Alternating current
Three-phase alternating
current
Three-phase alternating
current with neutral
Direct current
No load speed
Alternating or direct
current
Class II construction
Splash-proof
construction
Watertight construction
Protective grounding at
grounding terminal,
Class I tools
Revolutions or
reciprocations per
minute
Diameter
Off position
Arrow
Warning symbol
Wear your safety
glasses
WARNING: Some of the following symbols may appear on the sander.
Study these symbols and learn their meaning. Proper interpretation of these
symbols will allow for more efficient and safer operation of this tool.
This symbol designates that this tool is
listed with U.S. requirements by
Underwriters Laboratories.
61TN
E213739
JD2617U

KNOW YOUR SANDER
ACCESSORIES
11
Vacuum
port
Main handle
Front handle
Cooling
vents
ON/OFF
trigger switch
Lock-on
button
Cooling
vents
Backing
pad
Front
sandpaper
clamp
Sandpaper
clamp lever
Rear
sandpaper
clamp
AVAILABLEACCESSORIES
WARNING: Use only sandpaper
that is recommended for this sander.
Follow the instructions that accompany
the sandpaper. The use of improper
accessories may result in injury to the
operator or damage to the sander.
Before using any accessory, carefully read
the instructions or the owner’s manual for
the accessory.
Sandpaper
WARNING: If any part is missing or
damaged, do not plug the sander into the
power source until the missing or damaged
part is replaced.

CONTENTS
12
CONTENTS
Carefully unpack the sander. Compare the
contents against the “SANDER
COMPONENTS” chart at right.
NOTE: See illustration of the sander
below.
WARNING: To avoid fire or toxic
reaction, never use gasoline, naphtha,
acetone, lacquer thinner or similar
highly volatile solvents to clean the
tool.
SANDER COMPONENTS
KEY
DESCRIPTION
QTY
A
Sander
1
B
Dust port adapter
1
C
Vacuum adaptor
1
D
Sandpaper
60 grit
80 grit

120 grit
1
1
1
E
Sandpaper hole punch
1
Owner’s Manual
1
A
BC
D
E

ASSEMBLY AND OPERATING
13
INSTALLING SANDPAPER
WARNING: Unplug the sander
from the power source before installing
or changing sandpaper.
1. Lift upward and outward on the
sandpaper clamp levers (1) located at
each side of the sander base (2)
(Fig. 1). This will release the
sandpaper clamps (3) that are located
at the front and rear of the sander
base.
2. Insert one end of the 1/3 sheet
sandpaper (4) with its grit side up into
the open front sandpaper clamp (5),
making sure it is aligned with the
backing pad (Fig. 2). Lift the
sandpaper clamp lever upward and
inward to lock the sandpaper into
clamp.
3. Wrap the sandpaper sheet (4) over
backing pad (6) and insert it into the
open rear sandpaper clamp (7)
(Fig. 3).
NOTE: Make sure the sandpaper is pulled
tightly over the backing pad for proper
sanding operation.
4. Lift the sandpaper clamp lever up and
inward to lock the sandpaper into
clamp.
PUNCHING HOLES IN SANDPAPER
When new sandpaper is installed on the
sander, place the corner of the sander
base into the sandpaper hole punch with
the base plate corner (1) nested into the
corner of the hole punch (2). Press the
base plate firmly into the hole punch. The
sharp pins (3) will piece the sandpaper (4)
to allow it to extract the sanding dust.
Fig. 1
Fig. 2
Fig. 3
Fig. 4

ASSEMBLY AND OPERATING
14
ON/OFF TRIGGER SWITCH
To turn the sander ON, squeeze the trigger
switch (1) Fig. 5). To turn the sander OFF,
release the trigger switch.
LOCK-ON BUTTON
Your sander is equipped with a lock-on
feature, which is convenient when
continuously sanding for extended periods
of time is required (Fig. 6). To lock the
switch ON, depress the trigger switch (1),
push in and hold the lock-on button (2)
located at the left side of the handle, then
release the trigger. Release the lock-on
button and your sander will continue
running. To turn the sander OFF, depress
and release the trigger switch to release
the lock-on button.
INSTALLING THE VACUUM ADAPTER
To reduce the amount of loose sawdust
produced while sanding, a workshop
vacuum can be attached to the sander by
using the vacuum adapter system.
1. Slide the oval end of the dust port
adapter (1) over the dust port (2) on
the rear of the sander (Fig. 7).
NOTE: Make sure the locating pin (3) on
the dust port latches into the matching hole
(4) in the dust port adapter.
2. Push and twist the small end of the
vacuum adapter (5) into the dust port
adapter.
3. Insert the vacuum hose into the large
end of the vacuum adapter.
Fig. 6
Fig. 5
Fig. 7

ASSEMBLY AND OPERATING
15
SANDPAPER SELECTION
For safety reasons, the operator
must read the sections of this
Owner’s Manual entitled "GENERAL
SAFETY WARNINGS", "POWER
TOOL SAFETY", "SPECIFIC SAFETY
RULES", "EXTENSION CORD
SAFETY" and "SYMBOLS"before
using this sander.
WARNING
Selecting the correct grit and type of
sandpaper is extremely important in
achieving a high quality sanded finish.
Aluminum oxide, silicon carbide and other
synthetic abrasives are best for power
sanding.Natural abrasives such as flint
and garnet are too soft for economical
use in power sanding.
In general, coarse grit will remove most
material. Fine grit will produce the best
finish in all sanding operations.The
condition of the surface to be sanded will
determine which grit will do the best job.
Verify the following every time the
sander is used:
1. Sandpaper is in good condition
and properly installed on the
sander.
2. The workpiece is properly
secured and free from any
foreign objects.
3. Safety glasses, safety goggles,
or face shield is being worn.
4. Hearing protection and dust
mask are being worn.
Failure to adhere to these safety
rules can greatly increase the
chances of serious injury.

ASSEMBLY AND OPERATING
16
Fig. 8
SANDPAPER SELECTION–cont’d
NOTE: Where the sandpaper grits are
shown numerically, higher numbers
indicate finer grit and lower numbers
indicate coarser grit.
If the surface is rough, start with a coarse
grit and sand until the surface is uniform.
Medium grit may then be used to remove
scratches left by the coarser grit. Fine grit
should be used for finishing the surface.
Always continue sanding with each grit
until the surface is uniform.
SANDING
Clamp or otherwise secure your workpiece
to prevent it from moving under the sander
while being sanded.Secure the workpiece
in a vice if possible.
WARNING:Any unsecured
workpiece could be thrown toward the
operator causing injury.
Place the sander on the workpiece so the
complete sanding pad surface is in contact
with the workpiece. Turn the sander ON by
squeezing the trigger switch. Move the
sander slowly over the workpiece making
successive passes in parallel lines, circles
or crosswise movements. Because the
random orbital motion of the sanding pad
moves in tiny circles, it is not necessary to
move the sander with the grain or in the
same direction for successive passes
(Fig. 8).

ASSEMBLY AND OPERATING
17
SANDING - Cont’d
Upon completion of the sanding operation,
turn sander OFF by squeezing and
releasing the switch trigger. Wait until the
sanding disc comes to a complete stop
before removing it from the workpiece.
WARNING:Your sander should
only be turned ON when the entire
surface of the sanding padis in contact
with the workpiece. Failure to follow
this sanding procedure could result in
loose sandpaper which could result in
possible injury.
NOTE: Hold the sander with two hands,
using both the front and rear handles.
Be careful NOT to cover the motor cooling
vents with your hands. Covering the
cooling vents could cause the motor to be
damaged by overheating.
DO NOT FORCE THE SANDER. The
weight of the sander usually provides
adequate pressure. Let the sander and
sandpaper do the work. Applying added
pressure will slow the motor, increase the
wear on the sandpaper and greatly reduce
sander speed. Excessive pressure will
overload the motor causing possible
damage from the motor overheating. It will
also create an inferior finish on sanded
work. Any finish or resin on wood will
soften from the frictional heat, causing
sandpaper to become clogged quickly. Do
not sand in one spot too long as the
sander’s rapid action may remove too
much material, making the surface
uneven.
Extended periods of sanding may tend to
overheat the motor. If this occurs, turn
sander OFF, wait until the sanding pad
comes to a complete stop and remove it
from the workpiece. Check to make sure
your hands have not been covering the
cooling vents. Let the motor cool before
continuing sanding operation.

It has been found that electric tools are
subjected to accelerated wear and
possible premature failure when they are
used on fiberglass boats and sports cars,
wallboard, spackling compounds or
plaster. The chips and grindings from
these materials are highly abrasive to
electric tool parts such as bearings,
brushes, commutators, etc. Consequently,
it is not recommended that this tool be
used for extended work on any fiberglass
material, wallboard, spackling compounds
or plaster. During any use on these
materials it is extremely important that the
tool is cleaned frequently by blowing it out
with an air jet.
WARNING:Always wear safety
goggles or safety glasses with side
shields during all sanding operations. It
is critical that you also wear safety
goggles or safety glasses with side
shields and a dust mask while blowing
dust out of the sander with an air jet.
Failure to take these safety precautions
could result in permanent eye or lung
damage.
LUBRICATION
All of the bearings in this tool are
lubricated with a sufficient amount of high-
grade lubricant for the life of the unit under
normal conditions. Therefore, no further
lubrication is required.
GENERAL
WARNING: When servicing, use
only identical replacement parts. The
use of any other part may create a
hazard or cause product damage.
DO NOT use solvents when cleaning
plastic parts. Plastics are susceptible to
damage from various types of commercial
solvents and may be damaged by their
use. Use a clean cloth to remove dirt, dust,
oil, grease etc.
WARNING:Do not allow brake
fluids, gasoline, petroleum-based
products, penetrating oils, etc. to come
into contact with plastic parts. They
contain chemicals that can damage,
weaken or destroy plastic.
DO NOT abuse power tools. Abusive
practices can damage the tool and the
workpiece.
WARNING: DO NOT attempt to
modify tools or create accessories. Any
such alteration or modification is
misuse and could result in a hazardous
condition leading to possible serious
injury. It will also void the warranty.
MAINTENANCE
18

EXPLODED VIEW
19

PART LIST
20
Always order by PART NUMBER, not by key number.
Key #
Part #
Part Name
Quantity
1
160200
Cord set
1
2
322006
Cord guard
1
3
315895
Vacuum adaptor
1
4
500201
Tapping screw
2
5
315000
Cord clamp
1
6
163618
Switch
1
7
110096
Stator
1
8 520017 Bearing 607 1
9
321001
Bearing sleeve
1
10
300155
Housing
1
11
N/A
Inner lead
1
12
162406
Carbon brush
2
13
314506
Brush holder support
2
14
222806
Brush holder
2
15
100096
Rotor
1
16
314040
Fan
1
17
520013
Bearing 627
1
18
234502
Aluminum fan
1
19
520033
Bearing 6001
1
20
242508
Paper clamp
2
21
311605
Base plate
1
22
500209
Tapping screw
4
23
341005
Pad
1
24
320015
Seal ring
1
25
311677
Support bar
4
26
342200
Spacer
3
27
205526
Lining ring
1
28
311683
Front bearing seat
1
29
500200
Tapping screw
9
30
315896
Inner sleeve
1
WARNING: When servicing, use only original equipment replacement parts. The
use of any other parts may create a safety hazard or cause damage to the sander.
Any attempt to repair or replace electrical parts on this sandermay create a safety hazard
unless repairs are performed by a qualified technician. For more information call our
technical service department.