IMPORTANT: Your new tool has been engineered and manufactured to WEN’s highest standards for dependability,
ease of operation, and operator safety. When properly cared for, this product will supply you years of rugged,
trouble-free performance. Pay close attention to the rules for safe operation, warnings, and cautions. If you use
your tool properly and for its intended purpose, you will enjoy years of safe, reliable service.
NEED HELP? CONTACT US!
Have product questions? Need technical support? Please feel free to contact us:
TECHSUPPOR[email protected]1-847-429-9263 (M-F 8AM-5PM CST)
For replacement parts and the most up-to-date instruction manuals, visit WENPRODUCTS.COM
VARIABLE SPEED
FIBER-CEMENT SHEAR
Instruction Manual
MODEL 3670
CONTENTS
WELCOME 3
Introduction ..................................................................................................... 3
Specifications ................................................................................................... 3
SAFETY 4
General Safety Rules ........................................................................................ 4
Electrical Information ....................................................................................... 6
BEFORE OPERATING 7
Know Your Fiber-Cement Shear ........................................................................7
OPERATION & MAINTENANCE 7
Operation ......................................................................................................... 7
Maintenance ......................................................................................................9
Exploded View & Parts List .............................................................................10
Warranty Statement ........................................................................................12
To purchase accessories and replacement parts for your tool, visit WENPRODUCTS.COM
2
Replacement Blades (Parts 3670-001, 3670-003, 3670-004)
SPECIFICATIONS
INTRODUCTION
Thanks for purchasing the WEN Fiber-Cement Shear. We know you are excited to put your tool to work, but first,
please take a moment to read through the manual. Safe operation of this tool requires that you read and understand
this operator’s manual and all the labels affixed to the tool. This manual provides information regarding potential
safety concerns, as well as helpful assembly and operating instructions for your tool.
NOTE: The following safety information is not meant to cover all possible conditions and situations that may occur.
WEN reserves the right to change this product and specifications at any time without prior notice.
At WEN, we are continuously improving our products. If you find that your tool does not exactly match this manual,
please visit wenproducts.com for the most up-to-date manual or contact our customer service at 1-847-429-9263.
Keep this manual available to all users during the entire life of the tool and review it frequently to maximize
safety for both yourself and others.
Indicates danger, warning, or caution. The safety symbols and the explanations with them deserve your
careful attention and understanding. Always follow the safety precautions to reduce the risk of fire, electric shock
or personal injury. However, please note that these instructions and warnings are not substitutes for proper ac-
cident prevention measures.
Model Number 3670
Motor 120V, 60 Hz, 4A
Speed 0 to 2500 SPM
Maximum Cutting Capacity 0.5 Inches (13mm)
Head Swivel 360º
Product Weight 4.7 Pounds
Product Dimensions 11 in. x 3 in. x 8 in.
3
GENERAL SAFETY RULES
WORK AREA SAFETY
1. Keep work area clean and well lit. Cluttered or dark
areas invite accidents.
2. Do not operate power tools in explosive atmo-
spheres, such as in the presence of flammable liquids,
gases or dust. Power tools create sparks which may ig-
nite the dust or fumes.
3. Keep children and bystanders away while operating
a power tool. Distractions can cause you to lose control.
ELECTRICAL SAFETY
1. Power tool plugs must match the outlet. Never mod-
ify the plug in any way. Do not use any adapter plugs
with earthed (grounded) power tools. Unmodified plugs
and matching outlets will reduce risk of electric shock.
2. Avoid body contact with earthed or grounded surfac-
es such as pipes, radiators, ranges and refrigerators.
There is an increased risk of electric shock if your body
is earthed or grounded.
3. Do not expose power tools to rain or wet conditions.
Water entering a power tool will increase the risk of elec-
tric shock.
4. Do not abuse the cord. Never use the cord for car-
rying, 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.
5. When operating a power tool outdoors, use an ex-
tension cord suitable for outdoor use. Use of a cord
suitable for outdoor use reduces the risk of electric
shock.
6. If operating a power tool in a damp location is un-
avoidable, use a ground fault circuit interrupter (GFCI)
protected supply. Use of a GFCI reduces the risk of elec-
tric shock.
PERSONAL SAFETY
1. Stay alert, watch what you are doing and use com-
mon 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 inatten-
tion while operating power tools may result in serious
personal injury.
2. Use personal protective equipment. Always wear
eye protection. Protective equipment such as a respira-
tory mask, non-skid safety shoes and hearing protection
used for appropriate conditions will reduce the risk of
personal injury.
3. 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.
4. 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.
5. Do not overreach. Keep proper footing and balance
at all times. This enables better control of the power
tool in unexpected situations.
6. Dress properly. Do not wear loose clothing or jew-
elry. Keep your hair and clothing away from moving
parts. Loose clothes, jewelry or long hair can be caught
in moving parts.
Safety is a combination of common sense, staying alert and knowing how your item works. The term “power tool”
in the warnings refers to your mains-operated (corded) power tool or battery-operated (cordless) power tool.
SAVE THESE SAFETY INSTRUCTIONS.
WARNING! Read all safety warnings and all instructions. Failure to follow the warnings and instructions may
result in electric shock, fire and/or serious injury.
4
GENERAL SAFETY RULES
7. 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
1. 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.
2. 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.
3. 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.
4. 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 us-
ers.
5. 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 opera-
tion. If damaged, have the power tool repaired before
use. Many accidents are caused by poorly maintained
power tools.
6. Keep cutting tools sharp and clean. Properly main-
tained cutting tools with sharp cutting edges are less
likely to bind and are easier to control.
7. Use the power tool, accessories and tool bits, etc.
in accordance with these instructions, taking into ac-
count the working conditions and the work to be per-
formed. Use of the power tool for operations different
from those intended could result in a hazardous situa-
tion.
8. Use clamps to secure your workpiece to a stable
surface. Holding a workpiece by hand or using your
body to support it may lead to loss of control.
9. KEEP GUARDS IN PLACE and in working order.
SERVICE
1. 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 main-
tained.
CALIFORNIA PROPOSITION 65 WARNING
Some dust created by power sanding, sawing, grinding,
drilling, and other construction activities may contain
chemicals, including lead, known to the State of Califor-
nia to cause cancer, birth defects, or other reproductive
harm. Wash hands after handling. Some examples of
these chemicals are:
• Lead from lead-based paints.
• Crystalline silica from bricks, cement, and other
masonry products.
• 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 ex-
posure to these chemicals, work in a well-ventilated area
with approved safety equipment such as dust masks
specially designed to filter out microscopic particles.
Safety is a combination of common sense, staying alert and knowing how your item works. The term “power tool”
in the warnings refers to your mains-operated (corded) power tool or battery-operated (cordless) power tool.
SAVE THESE SAFETY INSTRUCTIONS.
WARNING! Read all safety warnings and all instructions. Failure to follow the warnings and instructions may
result in electric shock, fire and/or serious injury.
5
ELECTRICAL INFORMATION
AMPERAGE
REQUIRED GAUGE FOR EXTENSION CORDS
25 ft. 50 ft. 100 ft. 150 ft.
4A 18 gauge 16 gauge 16 gauge 14 gauge
IMPORTANT: Servicing a double-insulated product requires extreme care and knowledge of the system, and
should be done only by qualified service personnel using identical replacement parts. Always use original factory
replacement parts when servicing.
1. Polarized Plugs. To reduce the risk of electric shock, this equipment has a polarized plug (one blade is wider
than the other). This plug will fit in a polarized outlet only one way. If the plug does not fit fully in the outlet, reverse
the plug. If it still does not fit, contact a qualified electrician to install a proper outlet. Do not modify the machine
plug or the extension cord in any way.
2. Ground fault circuit interrupter protection (GFCI) should be provided on the circuit or outlet used for this power
tool to reduce the risk of electric shock.
3. Service and repair. To avoid danger, electrical appliances must only be repaired by a qualified service technician
using original replacement parts.
GUIDELINES AND RECOMMENDATIONS FOR EXTENSION CORDS
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. The table below shows
the correct size to be used according to cord length and ampere rating. When in doubt, use a heavier cord. The
smaller the gauge number, the heavier the cord.
DOUBLE-INSULATED TOOL
The tool’s electrical system is double-insulated where two systems of insulation are provided. This
eliminates the need for the usual three-wire grounded power cord. Double-insulated tools do not need
to be grounded, nor should a means for grounding be added to the product. All exposed metal parts are
isolated from the internal metal components with protecting insulation.
1. Examine extension cord before use. Make sure your extension cord is properly wired and in good condition.
Always replace a damaged extension cord or have it repaired by a qualified person before using it.
2. Do not abuse extension cord. Do not pull on cord to disconnect from receptacle; always disconnect by pulling on
plug. Disconnect the extension cord from the receptacle before disconnecting the product from the extension cord.
Protect your extension cords from sharp objects, excessive heat and damp/wet areas.
3. Use a separate electrical circuit for your tool. This circuit must not be less than a 12-gauge wire and should be
protected with a 15A time-delayed fuse. Before connecting the motor to the power line, make sure the switch is in
the OFF position and the electric current is rated the same as the current stamped on the motor nameplate. Running
at a lower voltage will damage the motor.
6
KNOW YOUR FIBER-CEMENT SHEAR
Blade
360º Swivel Head
Locking Hex Screws
Power Lock
Power Trigger
NOTE: Maintain tools with care. This tool requires no additional lubrication. Never use water or chemical cleaner
to clean your power tool. Wipe clean with a dry cloth. Always store your power tool in a dry place away from the
reach of children. Keep the motor ventilation slots clean and free of debris. Periodically clean debris from the guard
and base. Occasionally, a small spark may ignite within the ventilation slots. This is a normal result of the carbon
brushes and will not damage your tool.
VARIABLE SPEED TRIGGER SWITCH AND LOCK BUTTON
Your WEN Variable Speed Fiber-Cement Shear is equipped with a pressure sensitive variable speed trigger and a
lock button for easy use.
1. Press the power trigger to start the shear. Release the power trigger to stop. Pressing the power trigger down
further will increase the stroke speed of the shear.
2. The shear can be locked at its maximum speed. Press the power trigger down all the way. Lock it in place by
simultaneously pressing the power lock button. The shear will now be locked at its highest speed. To turn the tool
off, squeeze and then release the power trigger.
OPERATION
WARNING! To avoid injury from accidental startups, turn the power switch OFF and remove the plug from
the power source outlet before making any adjustments.
WARNING! Never set the tool down during operation. Always have a firm grasp on the tool when it is
running.
7
Power Cord
OPERATING THE SHEAR
Before cutting your workpiece, make some practice cuts on a
piece of scrap material to make sure that you can adequately
operate the tool.
Place the shearing blades at the edge of the workpiece with
the fiber cement board sitting between the upper and lower
blades.
Squeeze the power trigger to your preferred speed. Gradually
move the blade through the material following your desired
pattern. Never force the tool to do a job that it cannot handle.
ADJUSTING THE SWIVEL HEAD
The head of the shear can be rotated up to 360 degrees de-
pending on the requirements of your workpiece. Unplug the
shear from the power source. Loosen the three hex screws
found along the edge of the head (Fig. 1 - 1). Once loosened,
rotate the head of the unit to the desired position and retighten
the hex screws. Make sure all hex screws are secure before
attempting to power and operate the device.
REPLACING THE CUTTING BLADE
After extended use, the cutting blade will become dull and
OPERATION
need replacing.
1. Remove the three hex screws (Fig. 1 - 1) located around the outer edge of the swivel head to remove it from the
shear. Set them to the side for safe keeping.
2. Carefully slide the blades out from the shear, taking note as to the way they are configured. Watch for the two
spacers included in the blade assembly: one can be found through the neck of the middle blade while the other is
threaded through the center hex screw (Fig. 1 - 1). Make sure not to lose these.
3. Replace with the new blades. Place the spacers in as necessary. Once they have all been placed in the same con-
figuration as the original blades, insert the spacers and the hex screws. Wait to fully tighten the hex screws until the
head has been placed back onto the body of the unit.
Fig. 1
1
8
MAINTENANCE
ROUTINE INSPECTION
Before each use, inspect the general condition of the tool.
Check for:
• Loose hardware
• Misalignment or binding of moving parts
• Damaged cord/electrical wiring
• Cracked or broken parts
• Any other condition that may affect its safe operation
SERVICE
Preventive maintenance performed by unauthorized personnel may result in misplacing of internal wires and com-
ponents, possibly causing a serious hazard. We recommend that all tool service be performed by a WEN Service
Center or Authorized WEN Service Station.
TOOL LUBRICATION
Your tool has been properly lubricated and is ready to use. No additional lubrication is required.
CARBON BRUSHES
The brushes in your tool have been engineered for many hours of dependable service. To maintain peak efficiency of
the motor, we recommend examining the brushes every two to six months. Only genuine WEN replacement brushes
designed specifically for your tool should be used. The brushes can be reached by unscrewing the four screws along
the handle and removing the left half of the handle’s housing. Replacement carbon brushes (part no. 3650-030) are
available for purchase on wenproducts.com.
BEARINGS
Bearings that become noisy (due to heavy load or abrasive material cutting) should be replaced as soon as possible
to avoid overheating or motor failure.
PRODUCT DISPOSAL
Used power tools should not be disposed of together with household waste. This product contains electronic com-
ponents that should be recycled. Please take this product to your local recycling facility for responsible disposal and
to minimize its environmental impact.
WARNING! To avoid accidents, make sure the tool is powered OFF and unplugged from the electrical outlet
before cleaning or performing any maintenance. Servicing of the tool must be performed by a qualified technician.
WARNING! To avoid accidents, always disconnect the tool from the power supply before cleaning or
performing any maintenance. The tool may be cleaned most effectively with compressed dry air. Always wear
safety goggles when cleaning tools with compressed air.
WARNING! Certain cleaning agents and solvents damage plastic parts. Some of these are: gasoline, carbon
tetrachloride, chlorinated cleaning solvents, ammonia and household detergents that contain ammonia.
9
EXPLODED VIEW & PARTS LIST
10
No. Part No. Description Qty.
1 3670-001 Middle Blade 1
2 3650-002 Bushing 2
3 3670-003 Right Blade 1
4 3670-004 Left Blade 1
5 3650-005 Nut 3
6 3650-006 Blade Collar 1
7 3650-007 Screw 3
8 3650-008 Nut 1
9 3650-009 Bearing 1
10 3650-010 Bearing Sleeve 1
11 3650-011 Washer 1
12 3650-012 Washer 1
13 3650-013 Bearing 1
14 3650-014 Spring Washer 1
15 3650-015 Shaft 1
16 3650-016 Gear Box 1
17 3650-017 Pin 1
18 3650-018 Bearing 1
19 3650-019 Gear 1
20 3650-020 Gear Box Backing 1
No. Part No. Description Qty.
21 3650-021 Fan Shield 1
22 3650-022 Bearing 1
23 3650-023 Rotor 1
24 3650-024 Bearing 1
25 3650-025 Screw 3
26 3650-026 Rubber Washer 1
27 3650-027 Stator 1
28 3650-028 Right Label 1
29 3650-029 Carbon Brush Holder 2
30 3650-030 Carbon Brush 2
31 3650-031 Left Label 1
32 3650-032 Switch 1
33 3650-033 Screw 4
34 3650-034 Housing 1
35 3670-035 Screw 2
36 3650-035 Wire Collar 1
37 3650-036 Screw 2
38 3650-037 Sleeve 1
39 3650-038 Power Cord 1
EXPLODED VIEW & PARTS LIST
NOTE: Not all parts may be available for purchase. Parts and accessories that wear down over the course of
normal use are not covered under the warranty.
11
WARRANTY STATEMENT
WEN Products is committed to building tools that are dependable for years. Our warranties are consistent with this
commitment and our dedication to qualit
y.
LIMITED WARRANTY OF WEN PRODUCTS FOR HOME USE
GRE
AT LAKES TECHNOLOGIES, LLC (“Seller”) warrants to the original purchaser only, that all WEN
consumer
power tools will be free from defects in material or workmanship during personal use for a period of two (2) years
used
for professional or commercial use. Purchaser has 30 days from the date of purchase to report missing or
damaged parts.
SELLER’S
SOLE OBLIGATION AND YOUR EXCLUSIVE REMEDY under this Limited Warranty and, to the extent per-
mitted
by law, any warranty or condition implied by law, shall be the replacement of parts, without charge, which a
re
defective
in material or workmanship and which have not been subjected to misuse, alteration, careless handling,
misrepair
, abuse, neglect, normal wear and tear,
improper maintenance, or other conditions adversely affecting the
Product
or the component of the Product, whether by accident or intentionally, by persons other than Seller. To
make
a claim under this Limited Warranty, you must make sure to keep a copy of your proof of purchase that
clearly
-
dor
of Great Lakes Technologies, LLC. Purchasing through third party vendors, including but not limited to garage
sales,
pawn shops, resale shops, or any other secondhand merchant, voids the warranty included with this
product.
Contact [email protected] or 1-847-429-9263 with the following information to make arrangements:
your
shipping address, phone number, serial number, required part numbers, and proof of purchase. Damaged
or
defective parts and products may need to be sent to WEN before the replacements can be shipped out.
-
turning
a product for warranty service, the shipping charges must be prepaid by the purchaser. The product
must
be
shipped in its original container (or an equivalent), properly packed to withstand the hazards of shipment. The
product
must be fully insured with a copy of the proof of purchase enclosed. There must also be a description of
the
will be returned and shipped back to the pur
chaser at no charge for addresses within the contiguous United States.
THIS
LIMITED WARRANTY DOES NOT APPLY TO ITEMS THAT WEAR OUT FROM REGULAR USAGE OVER TIME,
INCLUDING
BELTS, BRUSHES, BLADES, BATTERIES, ETC. ANY IMPLIED WARRANTIES SHALL BE LIMITED IN
DUR
ATION TO TWO (2) YEARS FROM DATE OF PURCHASE. SOME STATES IN THE U.S. AND SOME CANADIAN
PROVINCES
DO NOT ALLOW LIMITATIONS ON HOW LONG AN IMPLIED WARRANTY LASTS, SO THE ABOVE LIMI-
TAT
ION MAY NOT APPLY TO YOU.
IN
NO EVENT SHALL SELLER BE LIABLE FOR ANY INCIDENTAL OR CONSEQUENTIAL DAMAGES (INCLUDING
BUT
NOT LIMITED TO LIABILITY FOR LOSS OF PROFITS) ARISING FROM THE SALE OR USE OF THIS PRODUCT.
SOME ST
ATES IN THE U.S. AND SOME CANADIAN PROVINCES DO NOT ALLOW THE EXCLUSION OR LIMITAT
ION
OF
INCIDENTAL OR CONSEQUENTIAL DAMAGES, SO THE ABOVE LIMITATION OR EXCLUSION MAY NOT APPLY
TO YOU.
THIS
LIMITED WARRANTY GIVES YOU SPECIFIC LEGAL RIGHTS, AND YOU MAY ALSO HAVE OTHER RIGHTS
WHICH
VARY FROM STATE TO STATE IN THE U.S., PROVINCE TO PROVINCE IN CANADA AND FROM COUNTRY
TO COUNT
RY.
THIS
LIMITED WARRANTY APPLIES ONLY TO ITEMS SOLD WITHIN THE UNITED STATES OF AMERICA, CANA-
DA
AND THE COMMONWEALTH OF PUERTO RICO. FOR WARRANTY COVERAGE WITHIN OTHER
COUNTRIES,
CONT
ACT THE WEN CUSTOMER SUPPORT LINE. FOR WARRANTY PARTS OR PRODUCTS REPAIRED UNDER
W
ARRANTY SHIPPING TO ADDRESSES OUTSIDE OF THE CONTIGUOUS UNITED STATES, ADDITIONAL
SHIPPING
CHARGES MAY APPLY.
V. 2023.03.22
12
