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Operator's Manual
ROUTER
Double Insulated
Model No.
315.175140
Save this manual for
future reference
CAUTION: Read and
follow all Safety Rules and
Operating Instructions before
first use of this product.
Soars, Roebuck and Co., 3333 Beverly Rd., Hoffman Estates, IL 60179 USA
Visit the Craftsman web page: www.sears.com/craftsman
972000-975
5-02
• Safety
• Features
• Adjustments
• Operation
• Maintenance
• Parts List
®
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• Table Of Contents .......................................................................................................................................... 2
• Warranty ......................................................................................................................................................... 2
• Introduction ..................................................................................................................................................... 2
• Rules for Safe Operation ............................................................................................................................. 3-4
• Product Specifications .................................................................................................................................... 5
• Unpacking ....................................................................................................................................................... 5
• Accessories .................................................................................................................................................... 5
• Features ......................................................................................................................................................... 6
• Adjustments ................................................................................................................................................. 7-9
• Operation ................................................................................................................................................... 9-13
• Maintenance ............................................................................................................................................ 14-15
• Exploded View and Repair Parts List...................................................................................................... 16-17
• Parts Ordering / Service ............................................................................................................................... 18
FULL ONE YEAR WARRANTY ON CRAFTSMANROUTER
Ifthis I:RAFTSMAN Router fails to give complete satisfaction within one year from the date of purchase,
RETURN IT TO THE NEAREST SEARS STORE IN THE UNITED STATES, and Sears will replace it, free of
charge.
Ifthis rRAFT$14AN Router is used for commercial or rental purposes, this warranty applies for only 90 days
from the date of pumhase.
This warranty gives you specific legal rights, and you may also have other rights which vary from state to state.
Sears, Roebuck and Co., Dept. 817 WA, Hoffman Estates, IL 60179
Your router has many features for making routing
operations more pleasant and enjoyable. Safety,
performance and dependability have been given top
pdority in the design of this router making it easy to
maintain and operate.
,_ CAUTION: Carefully road through thisentire
operator's manual before using your new router.
Pay close attention to the Rules for Safe
Operation, Warnings and Cautions. If you use
your router properly and only for what it is
intended, you will enjoy years of safe, reliable
service.
_IL Look for this symbol to point out important safety precautions. It means attentionH! Your
safety is involved.
,_ WARNING:
The operation of any router can result in foreign objects being thrown into your eyes, which
can result insevere eye damage. Before beginning power tool operation, always wear safety
goggles or safety glasses with side shields and a full face shield when needed. We
recommend Wide Vision Safety Mask for use over eyeglasses or standard safety glasses
with side shields, available at Sears Retail Stores. Always wear eye protection which is
marked to comply with ANSI Z87.1.
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Thepurposeof safetysymbolsIs to attract your attention to possible dangers. The safety symbols, and
the explanations with them, deserve your careful attention and understanding. The safety warnings do
not by themselves eliminate any danger. The instructions or warnings they give are not substitutes for
proper accident prevention measures.
SYMBOL MEANING
A
A
A
A
SAFETY ALERTSYMBOL:
Indicatesdanger, waming, or_ution. M_ beusedinco_un_ionwith_her_mbolsorpictogrsphs.
DANGER: Failure to obey a safety warning will result in serious injury to yourself or to others.
Always follow the safety precautions to reduce the risk of fire, electric shock and personal injury.
WARNING: Failure to obey a safety warning can result in serious injury to yourself or to others.
Always follow the safety precautions to reduce the risk of fire, electric shock and personal injury.
CAUTION: Failure to obey a safety warning may result in property damage or personal injury to
yourself or to others. Always follow the safety precautions to reduce the risk of fire, electric shock
and personal injury.
NOTE: Advises you of information or instructionsvital to the operation or maintenance of the equipment.
DOUBLE INSULATION
Double insulation is a concept in safety, in electric
power tools, which eliminates the need for the usual
thrae-wire grounded power cord. All exposed metal
parts are isolated from internal metal motor
components with protecting insulation. Double
insulated tools do not need to be grounded.
_i WARNING: Do not attempt to operate this tool
until you have read thoroughly and understand
completely all instructions, safety rules, etc.
contained in this manual. Failure to comply can
result in accidents involving fire, electric shock,
or serious personal injury. Save operator's
manual and review frequently for continuing safe
operation, and instructing others who may use
this tool.
READ ALL INSTRUCTIONS
• KNOW YOUR POWER TOOL. Read operator's
manual carefully. Learn its applications and
limitations as well as the specific potential hazards
related to this tool.
• GUARD AGAINST ELECTRICAL SHOCK by
preventing body contact with grounded surfaces.
For example; pipes, radiators, ranges, refrigerator
enclosures.
• KEEP GUARDS IN PLACE and in working order.
• KEEP WORK AREA CLEAN. Cluttered areas and
benches invite accidents.
• AVOID DANGEROUS ENVIRONMENT. Do
not use power tools in damp or wet locations or
expose to rain. Keep work area well lit.
IMPORTANT
Servicing of a tool with double insulation requires
extreme care and knowledge of the system and
should be performed only by a qualified service
technician. For service we suggest you return the tool
to your nearest Sears Store for repair. Always use
original factory replacement parts when servicing.
KEEP CHILDREN AND VISITORS AWAY. All
visitors should wear safety glasses and be kept a
safe distance from work area. Do not let visitors
contact tool or extension cord.
• STORE IDLE TOOLS. When not in use, tools
should be stored in a dry and high or locked-up
place - out of the reach of children.
• DO NOT FORCE TOOL. It will do the job better
and safer at the rate for which it was designed.
• USE RIGHT 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 a circular saw for cutting tree
limbs or logs.
• WEAR PROPER APPAREL. Do not wear loose
clothing or jewelry that can get caught in tool's
moving parts and cause personal injury. Rubber
gloves and nonskid footwear are recommended
when working outdoors. Wear protective hair
covering to contain long hair and keep it from being
drawn into nearby air vents.
• ALWAYS WEAR SAFETY GLASSES. Everyday
eyeglasses have only impact-resistant lenses; they
are not safety glasses.
B PROTECT YOUR LUNGS. Wear a face or dust
mask ifthe operation is dusty.
3
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• PROTECT YOUR HEARING. Wear hearing
protection during extended periods of operation.
• DO NOT ABUSE CORD. Never carry tool by cord
or yank it to disconnect from receptacle. Keep cord
from heat, oil, and sharp edges.
• SECURE WORK. Use clamps or a vise to hold
work. It is safer than using your hand and it frees
both hands to operate tool.
B DO NOT OVERREACH. Keep proper footing and
balance at all times. Do not use on a ladder or
unstable support. Secure tools when working at
elevated positions.
• MAINTAIN TOOLS WITH CARE. Keep tools sharp
and clean for best and safest performance. Follow
instructions for lubricating and changing accesso-
ries.
• DISCONNECT TOOLS. When not in use, before
servicing, or when changing attachments, tools
should be disconnected from power supply.
B REMOVE ADJUSTING KEYS AND WRENCHES.
Form habit of checking to see that keys and
adjusting wrenches are removed from tool before
turning it on.
B AVOID ACCIDENTAL STARTING. Do not carry
plugged-in tool with finger on switch. Be sure
switch is off when plugging in.
B MAKE SURE YOUR EXTENSION CORD IS IN
GOOD CONDITION. When using an extension
cord, be sure to use one heavy enough to carry the
current your product will draw. An undersized cord
will cause a drop in line voltage resulting in loss of
power and overheating. A wire gage size (A.W.G.)
of at least 14 is recommended for an extension
cord 100 feet or less in length. A cord exceeding
100 feet is not recommended. If in doubt, use the
next heavier gage. The smaller the gage number,
the heavier the cord.
• OUTDOOR USE EXTENSION CORDS. When tool
is used outdoors, use only extension cords suitable
for use outdoors. Outdoor approved cords are
marked with the suffix W-A, for example - SJTW-A
or SJOW-A.
B KEEP CUTTERS CLEAN AND SHARP. Sharp
cutters minimize stalling and kickback.
• KEEP HANDS AWAY FROM ROUTING AREA.
Keep hands away from cutters. Donot reach under-
neath work while cutteris rotating.Do notattempt to
remove material while cutteris rotating.
• NEVER USE IN AN EXPLOSIVE
ATMOSPHERE. Normal sparking of the motor
could ignite fumes.
• INSPECT TOOL CORDS PERIODICALLY and if
damaged, have repaired at your nearest Sears
Repair Center. Stay constantly aware of cord
location.
• INSPECT EXTENSION CORDS
PERIODICALLY and replace if damaged.
• KEEP HANDLES DRY, CLEAN, AND FREE
FROM OIL AND GREASE. Always use a clean
cloth when cleaning. Never use brake fluids,
gasoline, petroleum-based products, or any strong
solvents to clean your tool.
• STAY ALERT AND EXERCISE CONTROL. Watch
what you are doing and use common sense. Do
not operate tool when you are tired. Do not rush.
• 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.
• DO NOT USE TOOL IF SWITCH DOES NOT
TURN IT ON AND OFF. Have defective switches
replaced by an authorized service center.
• INSPECT FOR and remove atl nails from lumber
before routing.
• DO NOT operate this tool while under the influence
of drugs, alcohol, or any medication.
• POLARIZED PLUGS. To reduce the risk of electric
shock, this tool has a polarized plug (one blade is
wider than the other). This plug will fit in a polar-
ized outlet only one way. Ifthe plug does notfit
fully in the outlet, reverse the plug. If it still does
not fit, contact a qualified electrician to install the
proper outlet. Do not change the plug in any way.
• WHEN SERVICING USE ONLY IDENTICAL
CRAFTSMAN REPLACEMENT PARTS.
• WHEN USING THIS ROUTER WITH A ROUTER
TABLE, HELP PREVENT POSSIBLE SERIOUS
INJURY BY KEEPING THE CUTTER GUARDED
AT ALL TIMES. Use only router tables, with
guards, that have been designed for use on routers
that are ofthis type, size, and weight.
• DO NOT USE TOOL UNDER "BROWNOUT" OR
OTHER LOW VOLTAGE CONDITIONS. Also, do
not use with any device that could cause the power
supply voltage to change.
• SAVE THESE INSTRUCTIONS. Refer to them
frequently and use them to instruct others who may
use this tool. If youloan someone this tool, loan
them these instructions also.
SAVE THESE INSTRUCTIONS
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,_ 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 howoften 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.
Depth of cut 0 - 1-1/2 in.
Collet 1/4 in.
Horsepower 1-1/2
Rating 120 volts, 60 Hz, AC only
Your router has been shipped completely assembled.
Inspect itcarefully to make sure no breakage or
damage has occurred during shipping. If any parts are
damaged or missing, contact your nearest Sears
Retail Store to obtain replacement parts before
attempting to operate router. A wrench and this
Operator's Manual are also included.
THE FOLLOWING RECOMMENDED ACCESSORIES ARE
CURRENTLY AVAILABLE AT SEARS RETAIL STORES
Template Guide Bushings
Dovetail Template
Box Joint Template
Amperes 8
No load speed 25,000 RPM
Power cord 6 ft.
Net weight 8.13 Ibs.
_k WARNING: If any parts are missing, do not
operate this tool until the missing parts are
replaced. Failure to do so could result in possible
serious personal injury.
Butt Hinge Template
Multi-Purpose Router Guide
Rout - A - Form Pantograph
COMBI- VEINING
NATION BIT
PANEL
CUTrER
,_ WARNING: The use of attachments accessories not listed above be hazardous.
COREBOX
BIT
V-GROOVE
CHAMFER
,!,
STRAIGHT
FACE
BIT
COMB-
INATION
STRAIGHT
BEVEL
CUTTER
HINGE
MORTISING
BIT
DOVETAILRABBE1 OGEE,
CUTTER BIT ROMANO
BITS
[
L
*25895FORCARBIDETIPPEDEDGEFORMINGBITS
2589FORHIGHSPEEDSTEELEDGEFORMINGBITS
llll'1 III IIIIII
or
5
L_
*CARBIDETIPPEDBITS I
CHAMFER
might
COVE
BIT,
45°
BIT
BEAD ARBOR
QUARTER. 2589
BITS
ROUND !
wrrH2
BALL
3EARINGS
(1i2IN.&
S/SIN.)
*25895
I
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KNOW YOUR ROUTER
See Figure 1.
Before attempting to use any tool, familiarize yourself
with all operating features and safety requirements.
SWITCH
To turn your router on, depress the switch trigger.
Release switch trigger to turn your router off.
LOCK-ON BUTTON
The switch of your router is equipped with a lock-on
feature which is convenient when operating for
extended periods of time. To lock on, depress the
trigger, push in the lock button located on the side of
the handle, then while holding the lock button pushed
in, release the trigger. To release the lock, depress
the trigger and release.
CHIP SHIELD
A clear plastic chip shield is installed on the front of
your router for protection against flying dust and
chips. The shield is designed to fit the front opening of
the router base. If necessary to remove chip shield,
UPSIDEDOWN VIEW OF ROUTER
squeeze the tabs on each end and pull outward. To
replace, squeeze the tabs at each end, fit into
opening, then release. For your protection, do not
use router without chip shield properly In place.
WRENCH STORAGE AREA
Your router has a wrench storage area located on the
top end cap portion of the motor housing. When
installing or removing cutters, remove the wrench
from its storage area. Proper storage of wrench when
not in use will help reduce the possibility of losing
wrench.
ELECTRICAL CONNECTION
Your router has a precision built electric motor. It
should be connected to a power supply that is 120
volts, 60 Hz, AC only (normal household current).
Do not operate this tool on direct current (DC). A
substantial voltage drop will cause a loss of power
and the motor wil! overheat. If your router does not
operate when plugged into an outlet, double-check
the power supply.
SPINDLE
LOCK
DEPTH
ADJUSTING
RING
COLLETNUT
CHIPSHIELD POINT SUBBASE HANDLE Fig. 1
DEPTH
INDICATOR
RING
INDICATOR
POINT
WRENCH
STORAGE
AREA
POWER
WRENCH
LOCKING
KNOB
DEPTH
INDICATORRING
INDICATOR /
_ WARNING: Do not allow familiarity with your router to make you careless. Remember that a careless fraction
of a second is sufficient to inflictsevere injury.
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_1= WARNING: Your router should never be
connected to power supply when you are
assembling parts, making adjustments,
installing or removing cutters, cleaning,
or when not in use. Disconnecting router
will prevent accidental starting that could
cause serious personal injury.
INSTALLING/REMOVING CUTTERS
See Figures 2 and 3.
• Unplug your router.
_i WARNING: Failure to unplug your router could
result in accidental starting causing serious
injury.
• A spindle lock is located on the front of the motor
housing. To activate lock, push spindle lock in and
slide into lock position. See Figure 2.
,_ WARNING: To prevent damage to the spindle
or spindle lock, always allow motor to come to a
complete stop before engaging spindle lock.
SPINDLELOCK
TOLOCK
SPINDLE
Fig. 2
• Place your router upside down on table, then turn
collet nut with wrench until lock mechanism
interlocks. See Figure 3.
CUTTER
WRENCH
_i, WARNING: If you are changing a cutter
immediately after use, be careful not to touch the
cutter or collet with your hands or fingers. They
will get burned because of the heat buildup from
cutting. Always use the wrench provided.
• Remove cutters by turning collet nut counter-
clockwise enough to allow cutter to slip easily from
collet. See Figure 3. The collet is machined to
precision tolerances to fit cutters with 1/4 in.
diameter shanks.
• With your router still upside down on table, insert
shank of cutter into collet. The shank of your cutter
should be close to but not touching bottom of
collet.
• Tighten the collet nut securely by turning clockwise
with the wrench provided. See Figure 3. Push
spindle lock in and slide into unlock position.
Otherwise, the interlocking mechanism of the
spindle lock will not let you turn your router on.
COLLET
Fig. 3
Note: Spindle lock is spring loaded and will snap into
position when lock mechanism interlocks.
WARNING: Do not use cutters with undersized
shanks. Undersized shanks will not tighten
properly and could be thrown from tool causing
injury.
7
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DEPTH OF CUT ADJUSTMENTS
See Figures 4, 5, and 6.
We recommend that cuts be made at a depth not
exceeding 1/8 in. and that several passes be made to
reach depths of cut greater than 1/8 in.
• Unplug your router.
,_i WARNING: Failure to unplug your router could
result in accidental starting causing
serious injury.
• Place your router on a flat surface, loosen locking
knob, and turn depth adjusting ring until cutter is
inside subbase. See Figure 4.
TO
TIGHTEN
LOCKING
KNOB
TO
CUTrERATZERO
DEPTHOFCUT Fig. 5
• Position your router sothat the cutter can extend
below the subbase for desired depth setting.
See Figure 6.
DEPTH
ADJUSllNG
RING
DEPTH
RING
INDICATOR
CUTrER
INSIDESUBBASE ' SUBBASE Fig. 4
• Turn depth adjusting ring untiltip of cutter touches
flat surface. Turn the depth indicator ringuntil the
zero lines up with the indicator point on the base.
Note: The depth indicator ring is also a zero reset
indicator when setting cutter at zero depth of cut,
then it becomes the depth adjusting ring.
See Figure 5.
POIHT
CUTTEREXTENDED
BELOWSUBBASE Fig. 6
•Tum the depth adjusting ring to obtain the desired
depth of cut. The distance the cutter moves can be
read on the depth adjusting dng. Each mark on the
depth adjusting dng indicates 1/16 inch change in
depth setting. Indicator point is located on the
base.
• Tighten locking knob securely before operating
router.
8
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DEPTHOFCUTADJUSTMENTSWHEN
ROUTERISMOUNTEDTOA ROUTERTABLE
See Figure 7.
The depth of cut is readable from both sides of the depth
indicator ring. The bottom dng is convenient when using
your router mounted upside down to a router table. The
indicator point on the base can also be used when using
your router mounted to a router table.
Set the cutter at zero depth of cut, rotate depth
indicator ring to desired depth of cut on the scale,
then tighten locking knob securely.
FOR ROUTERTABLE USE ONLY
INDICATOR DEPTH
POINT INDICATORRING
Fig. 7
ROUTER TABLES
The use of Craftsman reuters on router tables offered
by other manufacturers has not been investigated for
compliance with applicable safety standards.
_ WARNING: Do not use with router tables that
fail to conform to safe wood working practices
and offer proper guarding for the cutter. Failure
to comply can result in an accident causing
possible serious injury.
HELPFUL HINTS
_/ Always clamp workpiece securely before muting.
_/ A safe operator isone who thinks ahead.
•/ Always wear eye protection when muting.
,/ Make setup adjustments carefully. Then double
check. Measure twice and cut once.
J Keep cutters clean and preperly sharpened.
4' Don't let familiarity make you careless.
J Study all safety rules and do the job safely.
/ Never place your hands in jeopardy.
J Make certain clamps can't loosen while in use.
J Test difficultsetups on scrap -- Don't waste
lumber.
J Pla'neach operation before you begin.
4" Provide for smoother operation by cleaning your
muter frequently. Shake muter or blow with an air
jet to remove sawdust buildup.
Think safety by thinking ahead.
ROUTING
See Figure 8.
For ease of operation and maintaining proper control,
your router has two handles, one on each side of the
router base. When using your router hold it firmly with
both hands as shown in Figure 8.
Turn router on and let motor build to its full speed,
then gradually feed cutter intoworkpiece. Remain
alert and watch what you are doing. Do not operate
router when fatigued.
HANDLE
POWER
HANDLE
PRACTICE BEFORE ACTUAL USE
We suggest that you practice with your router before
installing a cutter and making cuts in wood. Check
the following before connecting your router to
power supply.
• Make sure power supply is 120 volts, 60 Hz, AC
only.
• Make sure the spindle lock isinthe unlocked
position.
• Make sure the tdgger is not in the lock.on position.
• Make sure there is not a cutter in the toilet.
• Make sure the toilet does not extend below the
subbase.
• Plug your routerinto power supply.
• Grasp your routerfirmly with both hands and turn on.
,_ WARNING'- Keep a firm grip on router with both
hands at all times. Failure to do so could result in
loss of control leading to possible serious injury.
9
Fig. 8
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FREEHAND ROUTING
See Figure 9.
FREEHANDROUTING Fig. 9
When used freehand, your router becomes a flexible
and versatile tool. This flexibility makes it possible to
easily rout signs, relief sculptures, etc.
There are two basic techniques
for freehand routing:
• Routing letters, grooves, and patterns into wood.
See Figure 9.
• Routing out the background, leaving the letters
or pattern raised above the surface.
When freehand routing, we suggest the following:
• Draw or layout the pattern on workpiece.
• Choose the appropriate cutter.
Note: A core box or V-groove bit is often used for
routing letters and engraving objects. Straight bits
and ball mills are often used to make relief
carvings. Veining bitsare used to carve small,
intricate details.
• Rout the pattern in two or more passes. Make the
first pass at 25% of the desired depth of cut. This
will provide better control as well as being a guide
for the next pass.
• Do not rout deeper than 1/8 in. per pass or cut.
WARNING: Do not use large router bits for
A
freehand routing. Use of large router bits when
freehand routing could cause loss of control or
create other hazardous conditions that could
cause possible serious personal injury.When
using a router table, large router bits should be
used for edging only. Do not use router bits that
are larger in diameter than the opening in router
base for any purpose.
RATE OF FEED
IMPORTANT: The whole "secret" of professional
routing and edge shaping lies in making a careful
setup for the cut to be made and in selecting the
proper rate of feed.
PROPER FEEDING
The right feed is neither too fast nor too slow. It is the
rate at which the bit is being advanced firmly and
surely to produce a continuous spiral of uniform chips
-- without hogging into the wood to make large
individual chips or, on the other hand, to create only
sawdust. If you are making a small diameter, shallow
groove in soft, dry wood, the proper feed may be
about as fast as you can travel your router along your
guide line. On the other hand, ifthe bit is a large one,
the cut is deep or the wood is hard to cut, the proper
feed may be a very slow one. A cross-grain cut may
require a slower pace than an identical with grain cut
in the same workpiece.
There is no fixed rule. You will learn by experience
from practice and use. The best rate of feed is
determined by listening to the sound of the router
motor and by feeling the progress of each cut. Always
test a cut on a scrap piece of the workpiece wood,
beforehand.
FORCEFEEDING
Clean, smooth routing and edge shaping can be done
only when the bit is revolving at a relatively high
speed and istaking very small bites to produce tiny,
cleanly severed chips. If your router is forced to move
forward too fast, the RPM of the bit becomes slower
than normal in relation to its forward movement. As a
result, the bit must take bigger bites as it revolves.
"Bigger bites" mean bigger chips, and a rougher
finish. Bigger chips also require more power, which
could result in the router motor becoming overloaded.
Under extreme force-feeding conditions the relative
RPM of the bit can become so slow -- and the bites it
has to take so large -- that chips will be partially
knocked off (rather thanfully cut off), with resulting
splintering and gouging of the workpiece.
See Figure 10.
10
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TOOFAST
TOOSLOW Fig.10
Your router is an extremely high-speed tool (25,000
RPM no-load speed), and will make clean, smooth
cuts ifallowed to run freely without the overload of a
forced (too fast) feed. Three things that cause "force
feeding" are bit size, depth-of-cut, and workpiece
characteristics. The larger the bit or the deeper the
cut, the more slowly the router should be moved
forward. If the wood is very hard, knotty, gummy or
damp, the operation must be slowed stillmore.
You can always detect "force feeding" by the sound of
the motor. Its high-pitched whine will sound lower and
stronger as it loses speed. Also, the strain of holding
the tool will be noticeably increased.
TOO SLOW FEEDING
It is also possible to spoil a cut by moving the router
forward too slowly. When it is advanced into the work
too slowly, a revolving bit does not dig into new wood
fast enough to take a bite; instead, it simply scrapes
away sawdust-like particles. Scraping produces heat,
which can glaze, burn, or mar the cut -- in extreme
cases, can even overheat the bit so as to destroy its
hardness.
In addition, it is more difficult to control a routerwhen
the bit is scraping instead of cutting. With practically
no load on the motor the bit will be revolving at close
to top RPM, and will have a much greater than normal
tendency to bounce off the sides of the cut (especially
if the wood has a pronounced grain with hard and soft
areas). As a result,the cut produced may have
rippled, instead of straight sides. See Figure 10.
'q'oo-slow feeding" can also cause your router to take
off in a wrong directionfrom the intended line of cut.
Always grasp and hold your router firmly with
both hands when routing.
You can detect "too-slow feeding" by the runaway
too-highly pitched sound of the motor; or by feeling
the "wiggle" of the bit inthe cut.
DEPTH OF CUT
As previously mentioned, the depth of cut is important
because it affects the rate of feed which, inturn,
affects the quality of a cut (and, also, the possibilityof
damage to your router motor and bit). A deep cut
requires a slower feed than a shallow one, and a too
deep cut will cause you to slow the feed so much that
the bit is no longer cutting, it is scraping, instead.
Making a deep cut is never advisable. The smaller
bits --especially those only 1/16 inch in diameter-
are easily broken off when subjected to too much side
thrust. A large enough bit may not be broken off, but if
the cut is too deep a rough cut will result -- and it may
be very difficult to guide and controlthe bitas desired.
For these reasons, we recommend that you do not
exceed 118inch depth of cut in a single pass,
regardless of the bit size or the softness or condition
ofthe workpiece. See Figure 11.
DEPTH
WIDTH
OFCUT
OFIUT
W/YJ d
11
Fig. 11