Ryobi P503 User manual

OPERATOR’S MANUAL
5-1/2 in., 18 V
CIRCULAR SAW
P503
SAVE THIS MANUAL FOR FUTURE REFERENCE
Your circular saw has been engineered and manufactured to our high standard for dependability, ease of operation, and
operator safety. When properly cared for, it will give you years of rugged, trouble-free performance.
WARNING: To reduce the risk of injury, the user must read and understand the operator’s manual before using
this product.
Thank you for your purchase.
ACCEPTS ALL ONE+ BATTERY PACKS

2
Introduction ..................................................................................................................................................................... 2
Warranty .......................................................................................................................................................................... 2
General Safety Rules.................................................................................................................................................... 3-4
Specific Safety Rules.................................................................................................................................................... 4-5
Symbols........................................................................................................................................................................6-7
Features........................................................................................................................................................................... 8
Assembly .................................................................................................................................................................... 9-10
Operation.................................................................................................................................................................. 10-17
Adjustments................................................................................................................................................................... 18
Maintenance.............................................................................................................................................................18-19
Accessories ................................................................................................................................................................... 19
Parts Ordering / Service ...................................................................................................................................Back Page
TABLE OF CONTENTS
INTRODUCTION
This product has many features for making its use more pleasant and enjoyable. Safety, performance, and dependability
have been given top priority in the design of this product making it easy to maintain and operate.
WARRANTY
RYOBI®POWER TOOL - LIMITED TWO YEAR WARRANTY AND 30 DAY EXCHANGE POLICY
One World Technologies, Inc., warrants its RYOBI® power tools with the following conditions:
30-DAY EXCHANGE POLICY: During the first 30 days after date of purchase, you may either request service under this
warranty or you may exchange any RYOBI®power tool which does not work properly due to defective workmanship or
materials by returning the power tool to the dealer from which it was purchased. To receive a replacement power tool
or requested warranty service, you must present proof of purchase and return all original equipment packaged with the
original product. The replacement power tool will be covered by the limited warranty for the balance of the two year period
from the date of the original purchase.
WHAT THIS WARRANTY COVERS: This warranty covers all defects in workmanship or materials in your RYOBI®power
tool for a period of two years from the date of purchase. With the exception of batteries, power tool accessories are
warranted for ninety (90) days. Batteries are warranted for two years.
HOW TO GET SERVICE: Just return the power tool, properly packaged and postage prepaid, to an Authorized Service
Center. You can obtain the location of the Service Center nearest you by contacting a service representative at One
World Technologies, Inc., P.O. Box 1207, Anderson, SC 29622-1207, by calling 1-800-525-2579 or by logging on to
www.ryobitools.com. When you request warranty service, you must also present proof of purchase documentation, which
includes the date of purchase (for example, a bill of sale). We will repair any faulty workmanship, and either repair or replace
any defective part, at our option. We will do so without any charge to you. We will complete the work in a reasonable time,
but, in any case, within ninety (90) days or less.
WHAT’S NOT COVERED: This warranty applies only to the original purchaser at retail and may not be transferred. This
warranty only covers defects arising under normal usage and does not cover any malfunction, failure or defects resulting
from misuse, abuse, neglect, alteration, modification or repairs by other than Authorized Service Centers. One World
Technologies, Inc. makes no warranties, representations or promises as to the quality or performance of its power tools
other than those specifically stated in this warranty.
ADDITIONAL LIMITATIONS: Any implied warranties granted under state law, including warranties of merchantability or
fitness for a particular purpose, are limited to two years from the date of purchase. One World Technologies, Inc. is not
responsible for direct, indirect, or incidental damages, so the above limitations and exclusions may not apply to you. This
warranty gives you specific legal rights, and you may also have other rights which vary from state to state.

3
GENERAL SAFETY RULES
WARNING!
Read all instructions. Failure to follow all instructions
listed below may result in electric shock, fire and/or
serious injury. The term “power tool” in all of the warnings
listed below refers to your mains-operated (corded)
power tool or battery-operated (cordless) power tool.
SAVE THESE INSTRUCTIONS
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.
Use battery only with charger listed.
Use safety equipment. Always wear eye protection.
Safety equipment such as dust mask, non-skid safety
shoes, hard hat, or hearing protection used for appropriate
conditions will reduce personal injuries.
Avoid accidental starting. Ensure the switch is in the
off-position before plugging in. Carrying power tools
with your finger on the switch or plugging in 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 jewelry.
Keep your hair, clothing and gloves away from moving
parts. Loose clothes, jewelry 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 these devices can
reduce dust-related hazards.
Do not wear loose clothing or jewelry. Contain long
hair. Loose clothes, jewelry, or long hair can be drawn
into air vents.
Do not use on a ladder or unstable support. Stable
footing on a solid surface enables better control of the
power tool in unexpected situations.
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.
MODEL BATTERY PACK
(P104 Li-ion)
CHARGER
(P113)
P503
130429001, 130429002
140501001,
140501005
BATTERY PACK
(P100 Ni-Cd)
130255004, 130224028
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.

4
GENERAL SAFETY RULES
SPECIFIC SAFETY RULES
Use the power tool, accessories and tool bits etc., in
accordance with these instructions and in the manner
intended for the particular type of power tool, 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.
BATTERY TOOL USE AND CARE
Ensure the switch is in the off position before inserting
battery pack. Inserting the battery pack into power tools
that have the switch on invites accidents.
Recharge only with the charger specified by the
manufacturer. A charger that is suitable for one type
of battery pack may create a risk of fire when used with
another battery pack.
Use power tools only with specifically designated
battery packs. Use of any other battery packs may create
a risk of injury and fire.
When battery pack is not in use, keep it away from
other metal objects like paper clips, coins, keys, nails,
screws, or other small metal objects that can make a
connection from one terminal to another. Shorting the
battery terminals together may cause burns or a fire.
Under abusive conditions, liquid may be ejected from
the battery, avoid contact. If contact accidentally
occurs, flush with water. If liquid contacts eyes,
additionally seek medical help. Liquid ejected from the
battery may cause irritation or burns.
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.
WARNING!
To reduce the risk of injury, user must read instruction
manual.
When servicing a power tool, use only identical
replacement parts. Follow instructions in the
Maintenance section of this manual. Use of unauthorized
parts or failure to follow Maintenance instructions may
create a risk of shock or injury.
DANGER! Keep hands away from cutting area and the
blade. Keep your second hand on auxiliary handle or
motor housing. If both hands are holding the saw, they
cannot be cut by the blade.
Do not reach underneath the workpiece. The
guard cannot protect you from the blade below the
workpiece.
Adjust the cutting depth to the thickness of the
workpiece. Less than a full tooth of the blade teeth should
be visible below the workpiece.
Never hold piece being cut in your hands or across
your leg. Secure the workpiece to a stable platform.
It is important to support the work properly to minimize
body exposure, blade binding, or loss of control.
Hold tool by insulated gripping surfaces when
performing an operation where the cutting tool may
contact hidden wiring or its own cord. Contact with a
“live” wire will make exposed metal parts of the tool “live”
and shock the operator.
When ripping, always use a rip fence or straight edge
guide. This improves the accuracy of cut and reduces
the chance of blade binding.
Always use blades with correct size and shape
(diamond versus round) of arbor holes. Blades that
do not match the mounting hardware of the saw will run
eccentrically, causing loss of control.
Never use damaged or incorrect blade washers or
bolt. The blade washers and bolt were specially designed
for your saw for optimum performance and safety of
operation.
Do not crush, drop or damage battery pack. Do not
use a battery pack or charger that has been dropped
or received a sharp blow. A damaged battery is subject
to explosion. Properly dispose of a dropped or damaged
battery immediately.
If the power supply cord is damaged, it must be replaced
only by the manufacturer or by an authorized service
center to avoid risk.
CAUSES AND OPERATOR PREVENTION OF
KICKBACK:
Kickback is a sudden reaction to a pinched, bound, or
misaligned saw blade, causing an uncontrolled saw to lift
up and out of the workpiece toward the operator.
When the blade is pinched or bound tightly by the kerf
closing down, the blade stalls and the motor reaction drives
the unit rapidly back toward the operator.
If the blade becomes twisted or misaligned in the cut, the
teeth at the back edge of the blade can dig into the top
surface of the wood causing the blade to climb out of the
kerf and jump back toward the operator.
Kickback is the result of saw misuse and/or incorrect
operating procedures or conditions and can be avoided by
taking proper precautions, as given below:
Maintain a firm grip with both hands on the saw and
position your arms to resist kickback forces. Position
your body to either side of the blade, but not in line
with the blade. Kickback could cause the saw to jump
backwards, but kickback forces can be controlled by the
operator, if proper precautions are taken.

5
ADDITIONAL SAFETY RULES
Check damaged parts. Before further use of the
tool, a guard or other part that is damaged should
be carefully checked to determine that it will operate
properly and perform its intended function. Check for
alignment of moving parts, binding of moving parts,
breakage of parts, mounting, and any other conditions
that may affect its operation. A guard or other part that
is damaged should be properly repaired or replaced
by an authorized service center. Following this rule will
reduce the risk of shock, fire, or serious injury.
Inspect for and remove all nails from lumber before
using this tool. Following this rule will reduce the risk of
serious personal injury.
Do not operate tool while under the influence of drugs,
alcohol, or any medication. Following this rule will
reduce the risk of electric shock, fire, or serious personal
injury.
Do not place battery tools or their batteries near fire
or heat. This will reduce the risk of explosion and possibly
injury.
Batteries vent hydrogen gas and can explode in the
presence of a source of ignition, such as a pilot light.
To reduce the risk of serious personal injury, never use
any cordless product in the presence of open flame. An
exploded battery can propel debris and chemicals. If
exposed, flush with water immediately.
Do not charge battery tool in a damp or wet location.
Following this rule will reduce the risk of electric shock.
For best results, your battery tool should be charged
in a location where the temperature is more than
50°F but less than 100°F. Do not store outside or in
vehicles.
Under extreme usage or temperature conditions, bat-
tery leakage may occur. If liquid comes in contact with
your skin, wash immediately with soap and water, then
neutralize with lemon juice or vinegar. If liquid gets
into your eyes, flush them with clean water for at least
10 minutes, then seek immediate medical attention.
Following this rule will reduce the risk of serious personal
injury.
When blade is binding, or when interrupting a cut
for any reason, release the trigger and hold the saw
motionless in the material until the blade comes to a
complete stop. Never attempt to remove the saw from
the work or pull the saw backward while the blade
is in motion, or kickback may occur. Investigate and
take corrective actions to eliminate the cause of blade
binding.
When restarting a saw in the workpiece, center the
saw blade in the kerf and check that saw teeth are
not engaged into the material. If saw blade is binding,
it may walk up or kickback from the workpiece as the
saw is restarted.
Support large panels to minimize the risk of blade
pinching and kickback. Large panels tend to sag under
their own weight. Supports must be placed under the
panel on both sides, near the line of cut and near the
edge of the panel.
Do not use dull or damaged blades. Unsharpened
or improperly set blades produce narrow kerf causing
excessive friction, blade binding and kickback.
Blade depth and bevel adjusting locking levers must be
tight and secure before making cut. If blade adjustment
shifts while cutting, it may cause binding and kickback.
Use extra caution when making a “plunge cut” into
existing walls or other blind areas. The protruding blade
may cut objects that can cause kickback.
Check lower guard for proper closing before each use.
Do not operate saw if lower guard does not move freely
and close instantly. Never clamp or tie the lower guard
into the open position. If saw is accidentally dropped,
lower guard may be bent. Raise the lower guard with the
retracting handle. Make sure it moves freely and does
not touch the blade or any other part, in all angles and
depths of cut.
Check the operation of the lower guard spring. If the
guard and the spring are not operating properly, they
must be serviced before use. Lower guard may operate
sluggishly due to damaged parts, gummy deposits, or a
buildup of debris.
Lower guard should be retracted manually only for
special cuts, such as “plunge cuts” and “compound
cuts.” Raise lower guard by retracting handle. As soon
as blade enters the material, the lower guard must be
released. For all other sawing, the lower guard should
operate automatically.
Always observe that the lower guard is covering the
blade before placing saw down on bench or floor. An
unprotected, coasting blade will cause the saw to walk
backwards, cutting whatever is in its path. Be aware
of the time it takes for the blade to stop after switch is
released.
Know your power tool. Read operator’s manual
carefully. Learn its applications and limitations, as
well as the specific potential hazards related to this
power tool. Following this rule will reduce the risk of
electric shock, fire, or serious injury.
Always wear safety glasses with side shields. Everyday
glasses have only impact resistant lenses. They are NOT
safety glasses. Following this rule will reduce the risk of
eye injury.
Protect your lungs. Wear a face or dust mask if the
operation is dusty. Following this rule will reduce the risk
of serious personal injury.
Protect your hearing. Wear hearing protection during
extended periods of operation. Following this rule will
reduce the risk of serious personal injury.
Battery tools do not have to be plugged into an
electrical outlet; therefore, they are always in
operating condition. Be aware of possible hazards when
not using your battery tool or when changing accessories.
Following this rule will reduce the risk of electric shock,
fire, or serious personal injury.
SPECIFIC SAFETY RULES

6
SYMBOLS
Some of the following symbols may be used on this product. Please study them and learn their meaning. Proper
interpretation of these symbols will allow you to operate the product better and safer.
SYMBOL NAME DESIGNATION/EXPLANATION
V Volts Voltage
A Amperes Current
Hz Hertz Frequency (cycles per second)
W Watt Power
min Minutes Time
Alternating Current Type of current
Direct Current Type or a characteristic of current
n
o
No Load Speed Rotational speed, at no load
Class II Tool Double-insulated construction
.../min Per Minute Revolutions, strokes, surface speed, orbits etc., per minute
Wet Conditions Alert Do not expose to rain or use in damp locations.
Read The Operator’s Manual To reduce the risk of injury, user must read and understand
operator’s manual before using this product.
Eye Protection Always wear safety goggles or safety glasses with side shields and,
as necessary, a full face shield when operating this product.
Safety Alert Precautions that involve your safety.
No Hands Symbol Failure to keep your hands away from the blade will result in serious
personal injury.
No Hands Symbol Failure to keep your hands away from the blade will result in serious
personal injury.
No Hands Symbol Failure to keep your hands away from the blade will result in serious
personal injury.
No Hands Symbol Failure to keep your hands away from the blade will result in serious
personal injury.
Hot Surface To reduce the risk of injury or damage, avoid contact with any hot
surface.

7
SYMBOLS
SERVICE
Servicing requires extreme care and knowledge and should
be performed only by a qualified service technician. For
service we suggest you return the product to the nearest
AUTHORIZED SERVICE CENTER for repair. When
servicing, use only identical replacement parts.
WARNING:
To avoid serious personal injury, do not attempt
to use this product until you read thoroughly and
understand completely the operator’s manual. If you
do not understand the warnings and instructions in the
operator’s manual, do not use this product. Call Ryobi
customer service for assistance.
WARNING:
SAVE THESE INSTRUCTIONS
The operation of any power tool can result in foreign objects being thrown into your eyes, which can
result in severe eye damage. Before beginning power tool operation, always wear safety goggles or
safety glasses with side shields and, when needed, a full face shield. We recommend Wide Vision
Safety Mask for use over eyeglasses or standard safety glasses with side shields. Always use eye
protection which is marked to comply with ANSI Z87.1.
The following signal words and meanings are intended to explain the levels of risk associated with this product.
SYMBOL SIGNAL MEANING
DANGER: Indicates an imminently hazardous situation, which, if not avoided, will result
in death or serious injury.
WARNING: Indicates a potentially hazardous situation, which, if not avoided, could result
in death or serious injury.
CAUTION: Indicates a potentially hazardous situation, which, if not avoided, may result in
minor or moderate injury.
CAUTION: (Without Safety Alert Symbol) Indicates a situation that may result in property
damage.

8
FEATURES
Fig. 1
PRODUCT SPECIFICATIONS
Motor..................................................................18 Volt DC
Blade Diameter.......................................................5-1/2 in.
Blade Arbor ............................................................... 3/8 in.
Cutting Depth at 0º...............................................1-9/16 in.
Cutting Depth at 45º...............................................1-1/8 in.
Charger Input.................................... 120 V, 60 Hz, AC only
No Load Speed ..................................... 4,200 r/min. (RPM)
LOCK-OFF
BUTTON
SWITCH
TRIGGER
DEPTH
ADJUSTMENT
KNOB
WIDTH OF
CUT SCALE
BEVEL
ADJUSTMENT
KNOB
BLADE
WRENCH
STORAGE
SPINDLE
LOCK BUTTON
KNOW YOUR CIRCULAR SAW
See Figure 1.
The safe use of this product requires an understanding of
the information on the product and in this operator’s manual
as well as a knowledge of the project you are attempt-
ing. Before use of this product, familiarize yourself with all
operating features and safety rules.
BEVEL ADJUSTMENT KNOB
The bevel adjustment knob allows you to set the circular
saw for bevel cuts from 45° to 90°.
BLADE WRENCH STORAGE
Convenient wrench storage for quick blade changes.
DEPTH ADJUSTMENT KNOB
The depth adjustment knob adjusts the depth of cut from
0 in. to 1-1/2 in.
LOCK-OFF BUTTON
The lock-off button reduces the possibility of accidental
starting.
SPINDLE LOCK BUTTON
The spindle lock button allows you to secure the blade when
turning the blade screw.
WIDTH OF CUT SCALE
When making straight cross cuts or rip cuts, the scale can
be used to measure up to 4-1/2 in. on the right side of the
blade, and up to 1 in. on the left side of the blade.

9
ASSEMBLY
UNPACKING
This product requires assembly.
Carefully remove the product and any accessories from
the box. Make sure that all items listed in the packing list
are included.
Inspect the product carefully to make sure no breakage
or damage occurred during shipping.
Do not discard the packing material until you have care-
fully inspected and satisfactorily operated the product.
If any parts are damaged or missing, please call
1-800-525-2579 for assistance.
PACKING LIST
Circular Saw
5-1/2 in. Blade
Blade Wrench
Operator’s Manual
WARNING:
If any parts are damaged or missing do not operate this
product until the parts are replaced. Failure to heed this
warning could result in serious personal injury.
WARNING:
Do not attempt to modify this product or create acces-
sories not recommended for use with this product. Any
such alteration or modification is misuse and could result
in a hazardous condition leading to possible serious
personal injury.
WARNING:
To prevent accidental starting that could cause serious
personal injury, always remove the battery pack from the
product when assembling parts.
ATTACHING THE BLADE
See Figure 2.
WARNING:
A 5-1/2 in. blade is the maximum blade capacity of the
saw. Never use a blade that is too thick to allow outer
blade washer to engage with the flats on the spindle.
Larger blades will come in contact with the blade guard,
while thicker blades will prevent blade screw from secur-
ing blade on spindle. Either of these situations could
result in a serious accident.
Remove the battery pack from the saw.
Remove the blade wrench (5 mm hex key) from the stor-
age area.
Depress the spindle lock button and remove the blade
screw and outer blade washer.
NOTE: Turn the blade screw clockwise to remove.
CAUTION:
To prevent damage to the spindle or spindle lock, always
allow motor to come to a complete stop before engaging
spindle lock.
NOTE: Do not run the circular saw with spindle lock en-
gaged.
Wipe a drop of oil onto the inner blade washer and outer
blade washer where they contact the blade.
Fig. 2
OUTER
BLADE WASHER
LOWER BLADE
GUARD LEVER
BLADE SCREW
BLADE
SPINDLE
SPINDLE
LOCK BUTTON
INNER BLADE
WASHER

10
BLADE
SCREW
ASSEMBLY
WARNING:
If inner blade washer has been removed, replace it before
placing blade on spindle. Failure to do so could cause an
accident since blade will not tighten properly.
Fit the saw blade inside the lower blade guard and onto
the spindle.
NOTE: The saw teeth point upward at the front of the
saw.
Replace the outer blade washer.
Depress the spindle lock button, then replace the blade
screw. Tighten the blade screw securely by turning it
counterclockwise.
Return the blade wrench to the storage area.
NOTE: Never use a blade that is too thick to allow the outer
blade washer to engage with the flats on the spindle.
REMOVING THE BLADE
See Figure 3.
Remove the battery pack from the saw.
Remove the blade wrench from the storage area.
Position the saw as shown, depress the spindle lock
button, and remove the blade screw by turning it clock-
wise.
Remove the outer blade washer.
Remove the blade.
Fig. 3
SPINDLE LOCK
TO LOOSEN
LOWER BLADE
GUARD LEVER
TO TIGHTEN
WARNING:
Do not allow familiarity with products to make you care-
less. Remember that a careless fraction of a second is
sufficient to inflict serious injury.
WARNING:
Always wear safety goggles or safety glasses with side
shields when operating products. Failure to do so could
result in objects being thrown into your eyes, resulting
in possible serious injury.
WARNING:
Do not use any attachments or accessories not recom-
mended by the manufacturer of this product. The use of
attachments or accessories not recommended can result
in serious personal injury.
APPLICATIONS
You may use this product for the purposes listed below:
Cutting all types of wood products (lumber, plywood,
paneling, composition board, and hard wood)
OPERATION

11
OPERATION
This product will accept Ryobi One+ 18 V lithium-ion battery
packs and Ryobi One+ 18 V nickel-cadmium battery packs.
Both types of battery packs are shown on this page. Following
pages will show the lithium-ion 18 V battery pack.
For complete charging instructions, refer to the operator’s
manual for the P113 charger. For battery pack instructions,
see the manual for the P104 lithium-Ion battery pack or the
P100 nickel-cadmium battery pack.
INSTALLING THE BATTERY PACK
See Figure 4.
NOTE: The battery pack is shipped in a low charge condi-
tion. Therefore, it must be charged prior to use. Refer to
CHARGING BATTERY PACK for charging instructions.
Place the battery pack in the saw. Align the raised rib
on the battery pack with the groove inside the saw, then
slide the battery pack into the saw.
Make sure the latches on each side of your battery pack
snap into place and the battery pack is secured in the
saw before beginning operation.
CAUTION:
When placing battery pack in the tool, be sure raised
rib on battery pack aligns with the bottom of the tool
and latches into place properly. Improper installa-
tion of the battery pack can cause damage to internal
components.
REMOVING THE BATTERY PACK
See Figure 4.
Locate the latches on the side of the battery pack and
depress them to release the battery pack from the saw.
Remove battery pack from the saw.
Fig. 4
DEPRESS LATCHES TO REMOVE BATTERY PACK
TO
INSTALL
WARNING:
Battery tools are always in operating condition. There-
fore, switch should always be locked when not in use or
carrying at your side.
Fig. 5
KICKBACK - BLADE SET TOO DEEP
Fig. 6
INCORRECT
SUPPORT
0
15
22.5
30
45
50
WRONG
KICKBACK
See Figures 5 - 8.
Kickback occurs when the blade stalls rapidly and the saw
is driven back towards you. Blade stalling is caused by any
action which pinches the blade in the wood.
DANGER:
Release switch immediately if blade binds or saw stalls.
Kickback could cause you to lose control of the saw. Loss
of control can lead to serious injury.
P100 NICKEL-CADMIUM
BATTERY PACK
P104 LITHIUM-ION
BATTERY PACK
OR

12
OPERATION
SAW BLADES
The best of saw blades will not cut efficiently if they are not
kept clean, sharp, and properly set. Using a dull blade will
place a heavy load on the saw and increase the danger of
kickback. Keep extra blades on hand, so that sharp blades
are always available.
Gum and wood pitch hardened on blades will slow the
saw down. Remove saw blade from the saw and use gum
and pitch remover, hot water, or kerosene to remove these
accumulations. DO NOT USE GASOLINE.
Fig. 7
Fig. 8
CORRECT
SUPPORT
CORRECT BLADE DEPTH SETTING = BLADE EXPOSED 1/4 in.
OR LESS ON UNDERSIDE OF WORKPIECE
0
15
22.5
30
45
50
To guard against kickback, avoid dangerous practices such
as the following.
Setting blade depth incorrectly.
Sawing into knots or nails in workpiece.
Twisting the blade while making a cut.
Making a cut with a dull, gummed up, or improperly set
blade.
Supporting the workpiece incorrectly.
Forcing a cut.
Cutting warped or wet lumber.
Operating the tool incorrectly or misusing the tool.
To lessen the chance of kickback, follow these safety prac-
tices.
Keep the blade at the correct depth setting. The depth
setting should not exceed 1/4 in. below the material being
cut.
Inspect the workpiece for knots or nails before cutting.
Never saw into a knot or nail.
Make straight cuts. Always use a straight edge guide
when rip cutting. This helps prevent twisting the blade.
Use clean, sharp, and properly set blades. Never make
cuts with dull blades.
Support the workpiece properly before beginning a cut.
Use steady, even pressure when making a cut. Never
force a cut.
Do not cut warped or wet lumber.
Hold the saw firmly with both hands and keep your body
in a balanced position so as to resist the forces if kickback
should occur.
WARNING:
When using the saw, always stay alert and exercise con-
trol. Do not remove the saw from the workpiece while the
blade is moving.

13
BLADE GUARD SYSTEM
See Figure 9.
The lower blade guard attached to the circular saw is there
for your protection and safety. Do not alter it for any reason.
If it becomes damaged, do not operate the saw until you
have the guard repaired or replaced. Always leave guard in
operating position when using the saw.
DANGER:
When sawing through work, lower blade guard does not
cover blade on the underside of work. Since blade is
exposed on underside of work, keep hands and fingers
away from cutting area. Any part of your body coming in
contact with moving blade will result in serious injury.
CAUTION:
Never use saw when guard is not operating correctly.
Check the guard for correct operation before each use.
The guard is operating correctly when it moves freely and
readily returns to the closed position. If you drop the saw,
check the lower blade guard and bumper for damage at
all depth settings before reuse.
STARTING/STOPPING THE SAW
See Figure 10.
To start the saw:
Depress the lock-off button.
Depress the switch trigger.
Always let the blade reach full speed, then guide the saw
into the workpiece.
WARNING:
The blade coming in contact with the workpiece before
it reaches full speed could cause the saw to “kickback”
towards you resulting in serious injury.
To stop the saw: release the switch trigger.
After you release the switch trigger, allow the blade to come
to a complete stop. Do not remove the saw from the
workpiece while the blade is moving.
OPERATION
Fig. 9
BLADE EXPOSED ON
UNDERSIDE OF WORKPIECE
LOWER BLADE GUARD
IS IN UP POSITION
WHEN MAKING A CUT
Fig. 10
SWITCH
LOCK-OFF
BUTTON
LOCK-OFF BUTTON
See Figure 10.
The lock-off button reduces the possibility of accidental
starting. The lock-off button is located on the handle above
the switch trigger. The lock-off button must be depressed
before you pull the switch trigger. The lock resets each time
the trigger is released.
NOTE: You can depress the lock-off button from either the
left or right side.

14
OPERATION
ADJUSTING BLADE DEPTH
See Figure 11.
Always keep correct blade depth setting. The correct blade
depth setting for all cuts should not exceed 1/4 in. below
the material being cut. More blade depth will increase the
chance of kickback and cause the cut to be rough. For
more depth of cut accuracy, a scale is located on the upper
blade guard.
Loosen the depth adjustment knob.
Determine the desired depth of cut.
Locate the depth of cut scale on the back of the upper
blade guard.
Hold the base flat against the workpiece and raise or
lower the saw until the indicator mark on bracket aligns
with the notch on the blade guard.
Tighten the depth adjustment knob securely.
Fig. 11
DEPTH
ADJUSTMENT
KNOB
OPERATING THE SAW
See Figures 12- 14.
It is important to understand the correct method for operat-
ing the saw. Refer to the figures in this section to learn the
correct and incorrect ways for handling the saw.
WARNING:
To make sawing easier and safer, always maintain proper
control of the saw. Loss of control could cause an acci-
dent resulting in possible serious injury.
DANGER:
When lifting the saw from the workpiece, the blade is
exposed on the underside of the saw until the lower blade
guard closes. Make sure the lower blade guard is closed
before setting the saw down.
To make the best possible cut, follow these helpful hints.
Hold the saw firmly with both hands.
Avoid placing your hand on the workpiece while making
a cut.
Support the workpiece so that the cut (kerf) is always to
your side.
Support the workpiece near the cut.
Clamp the workpiece securely so that the workpiece will
not move during the cut.
Always place the saw on the workpiece that is supported,
not the “cut off” piece.
Place the workpiece with the “good” side down.
Draw a guideline along the desired line of cut before
beginning your cut.
Fig. 12
WRONG Fig. 14
Fig. 13
WRONG

15
OPERATION
CROSS CUTTING/RIP CUTTING
See Figure 15.
When making a cross cut or rip cut, align the line of cut with
the outer blade guide notch on the base.
Since blade thicknesses vary, always make a trial cut in scrap
material along a guideline to determine how much, if any, you
must offset the guideline to produce an accurate cut.
NOTE: The distance from the line of cut to the guideline is
the amount you should offset the guide.
RIP CUTTING
See Figure 16.
Use a guide when making long or wide rip cuts with the
saw.
Secure the workpiece.
Clamp a straight edge to the workpiece using C-
clamps.
Saw along the straight edge to achieve a straight rip
cut.
NOTE: Do not bind the blade in the cut.
WIDTH OF CUT SCALE
See Figure 17.
A width of cut scale has been provided on the base of the
saw. When making straight cross cuts or rip cuts, the scale
can be used to measure up to 4-1/2 in. on the right side of
the blade, and up to 1 in. on the left side of the blade.
TOP VIEW OF SAW
GUIDELINE
BLADE
GUIDE NOTCH
FRONT
OF SAW
STRAIGHT
EDGE
WORKPIECE C-CLAMP
Fig. 15
Fig. 16
Fig. 17
WIDTH OF
CUT SCALE

16
Fig. 20
BEVEL CUTTING
See Figures 18 - 20.
Align the line of cut with the inner blade guide notch on
the base when making 45° bevel cuts.
Make a trial cut in scrap material along a guideline to
determine how much you should offset the guideline on
the cutting material.
Adjust the angle of the cut to any desired setting between
zero and 50°. Refer to Adjusting the Bevel Setting
next.
ADJUSTING THE BEVEL SETTING
See Figure 19.
Loosen the bevel adjustment knob.
Raise the motor housing end of the saw until you reach
the desired angle setting on the bevel scale.
Tighten the bevel adjustment knob securely.
WARNING:
Attempting a bevel cut without having the bevel adjust-
ment knob securely tightened can result in serious
injury.
MAKING A BEVEL CUT
See Figure 19.
Hold the saw firmly with both hands as shown.
Rest the front edge of the base on the workpiece.
Start the saw and let the blade reach full speed.
Guide the saw into the workpiece and make the cut.
Release the trigger and allow the blade to come to a
complete stop.
Lift the saw from the workpiece.
Fig. 18
Fig. 19
BLADE GUIDE NOTCH
BEVEL
ADJUSTMENT
KNOB
MOTOR
HOUSING
BEVEL
SCALE
BEVEL
ADJUSTMENT KNOB
BLADE
GUIDE NOTCH
LOWER
BLADE GUARD
GUIDELINE
BEVEL SCALE
OPERATION

17
OPERATION
POCKET CUTTING
See Figure 21.
WARNING:
Always adjust bevel setting to zero before making a
pocket cut. Attempting a pocket cut at any other setting
can result in loss of control of the saw possibly causing
serious injury.
Adjust the bevel setting to zero.
Set the blade to the correct blade depth setting.
Swing the lower blade guard up using the lower blade
guard handle.
NOTE: Always raise the lower blade guard with the handle
to avoid serious injury.
Hold the lower blade guard by the handle.
WARNING:
Never extend your fingers while holding the lower blade
guard handle. Extending your fingers may result in
contact with the blade, causing serious injury.
Rest the front of the base flat against the workpiece with
the rear of the handle raised so the blade does not touch
the workpiece.
Start the saw and let the blade reach full speed.
Guide the saw into the workpiece and make the cut.
Fig. 21
POCKET CUT LOWER BLADE
GUARD
LOWER BLADE
GUARD HANDLE
WARNING:
Always cut in a forward direction when pocket cutting.
Cutting in the reverse direction could cause the saw to
climb up on the workpiece and back toward you.
Release the trigger and allow the blade to come to a
complete stop.
Lift the saw from the workpiece.
Clear corners out with a hand saw or sabre saw.
WARNING:
Never tie the lower blade guard in a raised position. Leav-
ing the blade exposed could lead to serious injury.

18
MAINTENANCE
WARNING:
When servicing, use only identical replacement parts.
Use of any other parts may create a hazard or cause
product damage.
WARNING:
Always wear safety goggles or safety glasses with side
shields during power product operation or when blowing
dust. If operation is dusty, also wear a dust mask.
WARNING:
To avoid serious personal injury, always remove the
battery pack from the product when cleaning or
performing any maintenance.
GENERAL MAINTENANCE
Avoid using solvents when cleaning plastic parts. Most
plastics are susceptible to damage from various types of
commercial solvents and may be damaged by their use. Use
clean cloths to remove dirt, dust, oil, grease, etc.
WARNING:
Do not at any time let brake fluids, gasoline, petroleum-
based products, penetrating oils, etc., come in contact
with plastic parts. Chemicals can damage, weaken or
destroy plastic which may result in serious personal
injury.
Only the parts shown on the parts list are intended to be
repaired or replaced by the customer. All other parts should
be replaced at an Authorized Service Center.
50
Fig. 22
BEVEL
ADJUSTMENT
KNOB
BLADE
CARPENTER'S
SQUARE
ADJUSTMENT
SCREW
HEX NUT
0° BEVEL STOP
ADJUSTMENTS
WARNING:
To prevent accidental starting that could cause serious
personal injury, always remove the battery pack from the
product when making adjustments.
0° BEVEL STOP
See Figure 22.
The saw has a 0° bevel stop that has been factory adjusted
to assure 0° angle of the saw blade plate when making 90°
cuts.
CHECKING 0° BEVEL STOP
Place the saw in an upside down position on a work-
bench.
Check the squareness of the saw blade plate to the base
of the saw using a carpenter’s square.
ADJUSTING 0° BEVEL STOP
Loosen bevel adjustment knob.
Turn setscrew with hex key and adjust base until it is
square with the saw blade plate.
Tighten bevel adjustment knob securely.
WARNING:
Attempting a bevel cut without having the bevel adjust-
ment knob securely tightened can result in serious
injury.

19
ACCESSORIES
Look for these accessories where you purchased this product:
5-1/2 in. Thin Kerf Blade
Edge Guide
WARNING:
Current attachments and accessories available for use with this product are listed above. Do not use any attachments
or accessories not recommended by the manufacturer of this product. The use of attachments or accessories not
recommended can result in serious personal injury.
BATTERY PACK REMOVAL AND PREPARATION
FOR RECYCLING
To preserve natural resources, please
recycle or dispose of batteries
properly.
This product uses nickel-cadmium and
lithium-ion batteries. Local, state or
federal laws may prohibit disposal of
batteries in ordinary trash.
Consult your local waste authority for
information regarding available recycling
and/or disposal options.
WARNING:
Upon removal, cover the battery pack’s terminals with
heavy-duty adhesive tape. Do not attempt to destroy or
disassemble battery pack or remove any of its compo-
nents. Lithium-ion and nickel-cadmium batteries must
be recycled or disposed of properly. Also, never touch
both terminals with metal objects and/or body parts as
short circuit may result. Keep away from children. Failure
to comply with these warnings could result in fire and/or
serious injury.
Li - Ion
BATTERIES
This product will accept Ryobi One + 18 V lithium-ion batteries
or 18 V nickel-cadmium batteries. Length of service from each
charging will depend on the type of work you are doing.
The batteries for this product have been designed to provide
maximum trouble-free life. However, like all batteries, they
will eventually wear out. Do not disassemble battery pack
and attempt to replace the batteries. Handling of these
batteries, especially when wearing rings and jewelry, could
result in a serious burn.
To obtain the longest possible battery life, we suggest the
following:
For lithium-ion batteries:
Remove the battery pack from the charger once it is fully
charged and ready for use.
For battery pack storage longer than 30 days:
Store the battery pack where the temperature is below
80°F and away from moisture.
Store battery packs in a 30%-50% charged condition.
Every six months of storage, charge the pack as
normal.
For nickel-cadmium batteries:
Remove the battery pack from the charger once it is fully
charged and ready for use.
For battery pack storage longer than 30 days:
Store the battery pack where the temperature is below
80°F.
Store battery packs in a “discharged” condition.
MAINTENANCE

20
OPERATOR’S MANUAL
5-1/2 in., 18 VOLT
CIRCULAR SAW
P503
P503
987000-176
10-11-07 (REV:03)
• PARTS AND SERVICE
Prior to requesting service or purchasing replacement parts, please obtain your model
and serial number from the product data plate.
• MODEL NUMBER
• SERIAL NUMBER
• HOW TO OBTAIN REPLACEMENT PARTS:
Replacement parts can be purchased online at www.ryobitools.com or by calling
1-800-525-2579. Replacement parts can also be obtained at one of our Authorized
Service Centers.
• HOW TO LOCATE AN AUTHORIZED SERVICE CENTER:
Authorized Service Centers can be located online at www.ryobitools.com or by calling
1-800-525-2579.
• HOW TO OBTAIN CUSTOMER OR TECHNICAL SUPPORT:
To obtain Customer or Technical Support please contact us at 1-800-525-2579.
ONE WORLD TECHNOLOGIES, INC.
1428 Pearman Dairy Road, Anderson, SC 29625
Phone [phone]
www.ryobitools.com
RYOBI®is a registered trademark of Ryobi Limited used under license.
WARNING:
Some dust created by power sanding, sawing, grinding, drilling, and other construction activities contains
chemicals known 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 filter out microscopic particles.