Chicago Electric 93793 Installation manual

DUAL MIG WELDER
Model 93793
SET UP AND OPERATING INSTRUCTIONS
Visit our website at: http://www.harborfreight.com
Read this material before using this product.
Failure to do so can result in serious injury.
SAVE THIS MANUAL.
Copyright©2006 by Harbor Freight Tools®. All rights reserved. No portion of this manual or any artwork
contained herein may be reproduced in any shape or form without the express written consent of
Harbor Freight Tools. Diagrams within this manual may not be drawn proportionally. Due to continuing
improvements, actual product may differ slightly from the product described herein. Tools required for
assembly and service may not be included.
For technical questions or replacement parts, please call 1-800-444-3353.
Cover Revised 09l

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Contents
PRODUCT SPECIFICATIONS..............................................................3
GENERAL SAFETY RULES.................................................................3
Specic Safety Rules ....................................................................................... 6
Grounding ......................................................................................................... 9
Extension Cords .............................................................................................. 10
Symbology ....................................................................................................... 10
UNPACKING ........................................................................................10
ASSEMBLY INSTRUCTIONS..............................................................11
To Attach The Handle ...................................................................................... 11
To Install The Rear Wheels And Casters ....................................................... 11
To Install a 2 lb. Wire Spool ............................................................................ 12
To Install a 10 lb. Wire Spool .......................................................................... 12
To Route The Wire ........................................................................................... 13
To Change Wire Settings ................................................................................ 15
Setting The Gun Polarity For Wire Type........................................................ 16
To Attach The Ground Cable With Clamp ..................................................... 16
To Install A Gas Cylinder ................................................................................ 17
OPERATING INSTRUCTIONS ............................................................18
Before You Begin Welding.............................................................................. 18
Duty Cycle (Duration of Use).......................................................................... 18
Setting Up The Weld........................................................................................ 19
Holding The Welding Torch ............................................................................ 20
Weld Settings Chart ........................................................................................ 21
Weld Diagnosis................................................................................................ 23
When the Weld is Completed ......................................................................... 25
INSPECTION, MAINTENANCE, AND CLEANING .............................26
Nozzle Inspection, Cleaning, and Replacement ........................................... 26
Contact Tip Inspection, Cleaning, And Replacement .................................. 26
Replacing The Welding Torch Liner .............................................................. 27
Parts Lists and Diagrams ..................................................................28
Wiring Schematic ............................................................................................ 28
Parts List .......................................................................................................... 29
Assembly Diagram .......................................................................................... 30
TROUBLESHOOTING.........................................................................32
WARRANTY.........................................................................................34

Page 3For technical questions, please call 1-800-444-3353.SKU 93793
PRODUCT SPECIFICATIONS
Welding Current 35 ~ 140 A
Duty Cycle 18% @ 140 A / 100% @ 45 A
(Refer to chart and explanation on page 18)
Power Consumption 240 V~ / 60 Hz / 25 A
(Connect to a 25 A minimum dedicated circuit)
Open Voltage 15.5 - 20 V
Required Power Plug Type 3-Prong, 240 V~, polarized, twist lock (not included)
NEMA #L6-30 or equivalent
Power Cord Rating 12 AWG x 3C x 6’ Long
Gas Inlet Size 1/4”
Ground Cable 4 Gauge / 6’ Long
Torch Power Cable 8 Gauge / 6’ Long
Thermal Overload Protection (with Light) Automatic shutdown and restart after cool down
Wire Size 0.23” to 0.035”
Wire Spool Size 7-3/4” Diameter
Included Torch Tip Size 0.030”
Accessories Wheel Kit / Wire Spool / Torch Assy. / Grounding Clamp
Wire Brush & Hammer / Spare 1.0 & 0.8 Welding Tips
Hand-Held Face Shield
Net Weight 103 lb.
SAVE THIS MANUAL
You will need this manual for the safety warnings and precautions, assembly, operating,
inspection, maintenance and cleaning procedures, parts list and assembly diagram. Keep
your invoice with this manual. Write the invoice number on the inside of the front cover. Keep
this manual and invoice in a safe and dry place for future reference.
GENERAL SAFETY RULES
WARNING!
READ AND UNDERSTAND ALL INSTRUCTIONS
Failure to follow all instructions listed below may result in
electric shock, re, and/or serious injury.
SAVE THESE INSTRUCTIONS
WORK AREA
Keep your work area clean and well lit.1. Cluttered benches and dark areas invite
accidents.
Do not operate power tools in explosive atmospheres, such as in the presence of2.
ammable liquids, gases, or dust. Power tools create sparks which may ignite the dust
or fumes.
Keep bystanders, children, and visitors away while operating a power tool.3.
Distractions can cause you to lose control. Protect others in the work area from debris
such as chips and sparks. Provide barriers or shields as needed.

Page 4For technical questions, please call 1-800-444-3353.SKU 93793
ELECTRICAL SAFETY
Grounded tools must be plugged1.
into an outlet properly installed and
grounded in accordance with all
codes and ordinances. Never remove
the grounding prong or modify the
plug in any way. Do not use any
adapter plugs. Check with a qualied
electrician if you are in doubt as
to whether the outlet is properly
grounded. If the tools should electrically
malfunction or break down, grounding
provides a low resistance path to carry
electricity away from the user.
Avoid body contact with grounded2.
surfaces such as pipes, radiators,
ranges, and refrigerators. There is an
increased risk of electric shock if your
body is grounded.
Do not expose power tools to rain or3.
wet conditions. Water entering a power
tool will increase the risk of electric
shock.
Do not abuse the Power Cord.4. Never
use the Power Cord to carry the tools
or pull the Plug from an outlet. Keep
the Power Cord away from heat,
oil, sharp edges, or moving parts.
Replace damaged Power Cords
immediately. Damaged Power Cords
increase the risk of electric shock.
When operating a power tool5.
outside, use an outdoor extension
cord marked “W-A” or “W”. These
extension cords are rated for outdoor
use, and reduce the risk of electric
shock.
PERSONAL SAFETY
Stay alert. Watch what you are1.
doing, and use common sense when
operating a power tool. Do not use
a power tool while tired or under
the inuence of drugs, alcohol, or
medication. A moment of inattention
while operating power tools may result in
serious personal injury.
Dress properly. Do not wear loose2.
clothing or jewelry. Contain long hair.
Keep your hair, clothing, and gloves
away from moving parts. Loose
clothes, jewelry, or long hair can be
caught in moving parts.
Avoid accidental starting.3. Be sure the
Power Switch is off before plugging
in. Carrying power tools with your nger
on the Power Switch, or plugging in
power tools with the Power Switch on,
invites accidents.
Remove adjusting keys or wrenches4.
before turning the power tool on. A
wrench or a key that is left attached to a
rotating part of the power tool may result
in personal injury.
Do not overreach. Keep proper5.
footing and balance at all times.
Proper footing and balance enables
better control of the power tool in
unexpected situations.
Always wear eye, hearing, and6.
breathing protection. For welding
safety equipment, refer to number 9on
page 6.
TOOL USE AND CARE
Use clamps (not included) or other1.
practical ways to secure and support
the workpiece to a stable platform.
Holding the work by hand or against your
body is unstable and may lead to loss of
control.
Do not force the tool. Use the correct2.
tool for your application. The correct

Page 5For technical questions, please call 1-800-444-3353.SKU 93793
tool will do the job better and safer at the
rate for which it is designed.
Do not use the power tool if the Power3.
Switch does not turn it on or off. Any
tool that cannot be controlled with the
Power Switch is dangerous and must be
replaced.
Disconnect the Power Cord Plug from4.
the power source before making any
adjustments, changing accessories,
or storing the tool. Such preventive
safety measures reduce the risk of
starting the tool accidentally.
Store idle tools out of reach of5.
children and other untrained persons.
Tools are dangerous in the hands of
untrained users.
Maintain tools with care. Keep cutting6.
tools sharp and clean. Properly
maintained tools with a sharp cutting
edge are less likely to bind and are
easier to control. Do not use a damaged
tool. Tag damaged tools “Do not use”
until repaired.
Check for misalignment or binding of7.
moving parts, breakage of parts, and
any other condition that may affect
the tool’s operation. If damaged,
have the tool serviced before using.
Many accidents are caused by poorly
maintained tools.
Use only accessories that are8.
recommended by the manufacturer
for your model. Accessories that may
be suitable for one tool may become
hazardous when used on another tool.
SERVICE
Tool service must be performed only1.
by qualied repair personnel. Service
or maintenance performed by unqualied
personnel could result in a risk of injury.
When servicing a tool, use only2.
identical replacement parts. Follow
instructions in the “Inspection,
Maintenance, And Cleaning” section
of this manual. Use of unauthorized
parts or failure to follow maintenance
instructions may create a risk of electric
shock or injury.

Page 6For technical questions, please call 1-800-444-3353.SKU 93793
Specic Safety Rules
Ground this product.1. This Welder
requires the attachment and use
of a UL®-listed, 240 volt, grounded,
3-prong, electrical Power Cord Plug (not
included). Only a qualied electrician
should install the Power Cord Plug.
Never remove the grounding prong
or modify the Power Cord Plug in any
way. Do not use adapter plugs with this
product. To comply with the National
Electric Code, and to provide additional
protection from the risk of electrical
shock, this product should only be
connected to a 240 volt, 3-hole outlet
that is properly grounded.
Maintain labels and nameplates on2.
the Welder. These carry important
information. If unreadable or missing,
contact Harbor Freight Tools for a
replacement.
Avoid unintentional starting.3. Make
sure you are prepared to begin work
before turning on the Welder.
Do not force the Welder.4. This tool will
do the work better and safer at the speed
and capacity for which it was designed.
Never leave the Welder unattended5.
when it is plugged into an electrical
outlet. Turn off the tool, and unplug it
from its electrical outlet before leaving.
Industrial applications must follow6.
OSHA guidelines.
Never stand on the Welder.7. Serious
injury could result if the Welder is
tipped or if hot surfaces are accidently
contacted.
Maintain a safe working environment.8.
Keep the work area well lit. Make
sure there is adequate surrounding
workspace. Always keep the work area
free of obstructions, grease, oil, trash,
and other debris. Do not use a power
tool in areas near ammable chemicals,
dusts, and vapors. Do not use this
product in a damp or wet location.
9. Prevent eye injury and
burns. Wearing and using
ANSI-approved personal
safety clothing and safety
devices reduce the risk for injury.
Wear ANSI-approved safety impact•
eye goggles with a welding helmet with
protective lens.
Leather leggings, re resistant shoes or •
boots should be worn when using this
product. Do not wear pants with cuffs,
shirts with open pockets, or any clothing
that can catch and hold molten metal or
sparks.
Keep clothing free of grease, oil,•
solvents, or any ammable substances.
Wear dry, insulating gloves and
protective clothing.
Wear an approved head covering to•
protect the head and neck. Use aprons,
cape, sleeves, shoulder covers, and
bibs designed and approved for welding
and cutting procedures.
When welding/cutting overhead or in•
conned spaces, wear ame resistant
ear plugs or ear muffs to keep sparks
out of ears.
10. Prevent accidental res.
Remove any combustible
material from the work area.
When possible, move the work to a•
location well away from combustible
materials. If relocation is not possible,
protect the combustibles with a cover
made of re resistant material.
Remove or make safe all combustible•
materials for a radius of 35 feet (10

Page 7For technical questions, please call 1-800-444-3353.SKU 93793
meters) around the work area. Use a
re resistant material to cover or block
all open doorways, windows, cracks,
and other openings.
Enclose the work area with portable re •
resistant screens. Protect combustible
walls, ceilings, oors, etc., from sparks
and heat with re resistant covers.
If working on a metal wall, ceiling, etc.,•
prevent ignition of combustibles on the
other side by moving the combustibles
to a safe location. If relocation of
combustibles is not possible, designate
someone to serve as a re watch,
equipped with a re extinguisher, during
the cutting process and for at least one
half hour after the cutting is completed.
Do not weld or cut on materials having•
a combustible coating or combustible
internal structure, as in walls or ceilings,
without an approved method for
eliminating the hazard.
Do not dispose of hot slag in containers•
holding combustible materials. Keep a
re extinguisher nearby and know how
to use it.
After spot welding, make a thorough•
examination for evidence of re. Be
aware that easily-visible smoke or ame
may not be present for some time after
the re has started. Do not weld or cut
in atmospheres containing dangerously
reactive or ammable gases, vapors,
liquids, and dust. Provide adequate
ventilation in work areas to prevent
accumulation of ammable gases,
vapors, and dust. Do not apply heat to
a container that has held an unknown
substance or a combustible material
whose contents, when heated, can
produce ammable or explosive vapors.
Clean and purge containers before
applying heat. Vent closed containers,
including castings, before preheating,
welding, or cutting.
WARNING
INHALATION HAZARD:
Welding and Plasma Cutting Produce
TOXIC FUMES.
Exposure to welding or cutting exhaust
fumes can increase the risk of developing
certain cancers, such as cancer of the
larynx and lung cancer. Also, some
diseases that may be linked to exposure to
welding or plasma cutting exhaust fumes
are:
• Early onset of Parkinson’s Disease
• Heart disease • Ulcers
• Damage to the reproductive organs
• Inammation of the small intestine or
stomach • Kidney damage
• Respiratory diseases such as
emphysema, bronchitis, or pneumonia
Use natural or forced air ventilation and
wear a respirator approved by NIOSH to
protect against the fumes produced to
reduce the risk of developing the above
illnesses.
Avoid overexposure to fumes and12.
gases. Always keep your head out of
the fumes. Do not breathe the fumes.
Use enough ventilation or exhaust, or
both, to keep fumes and gases from your
breathing zone and general area.
Where ventilation is questionable,•
have a qualied technician take an air
sampling to determine the need for
corrective measures. Use mechanical
ventilation to improve air quality. If
engineering controls are not feasible,
use an approved respirator.

Page 8For technical questions, please call 1-800-444-3353.SKU 93793
Work in a conned area only if it is well •
ventilated, or while wearing an air-
supplied respirator.
Follow OSHA guidelines for Permissible•
Exposure Limits (PEL’s) for various
fumes and gases.
Follow the American Conference of•
Governmental Industrial Hygienists
recommendations for Threshold Limit
Values (TLV’s) for fumes and gases.
Have a recognized specialist in•
Industrial Hygiene or Environmental
Services check the operation and air
quality and make recommendations for
the specic welding or cutting situation.
Read and understand all instructions13.
and safety precautions as outlined
in the manufacturer’s manual for the
material you will weld or cut.
Do not touch live electrical parts14. .
Wear dry, insulating gloves. Do not
touch electrode or conductor tong with
bare hand. Do not wear wet or damaged
gloves.
Protect yourself from electric shock.15.
Do not use outdoors. Insulate yourself
from the workpiece and ground. Use
nonammable, dry insulating material
if possible, or use dry rubber mats, dry
wood or plywood, or other dry insulating
material big enough to cover your full
area of contact with the work or ground.
Ensure that the unit is placed on a16.
stable location before use. If this unit
falls while plugged in, severe injury,
electric shock, or re may result.
17. Cylinders can explode
when damaged:
Never weld on a pressurized or a closed•
cylinder.
Never lay a welding torch on a cylinder.•
Never allow a welding electrode to•
touch the cylinder.
Keep cylinders away from any electrical•
circuits, including welding circuits.
Keep protective cap in place over the•
valve except when the cylinder is in use.
Use only correct gas shielding•
equipment designed specically for the
type of welding you will do. Maintain
this equipment properly.
Always protect gas cylinders from heat,•
being struck, physical damage, slag,
ames, sparks, and arcs.
Always use proper procedures to move•
cylinders.
Use the right tool for the job.18. Do not
attempt to force small equipment to do
the work of larger industrial equipment.
There are certain applications for which
this Welder was designed. It will do
the job better and more safely at the
rate for which it was intended. Do not
modify this Welder, and do not use this
Welder for a purpose for which it was not
intended.
People with pacemakers should consult19.
their physician(s) before using this
product. Electromagnetic elds in close
proximity to a heart pacemaker could
cause interference to or failure of the
pacemaker.
The warnings and cautions discussed20.
in this manual cannot cover all possible
conditions and situations that may occur.
It must be understood by the operator
that common sense and caution are
factors which cannot be built into this
product, but must be supplied by the
operator.
WARNING!21. This product, when used
for welding and similar applications,

Page 9For technical questions, please call 1-800-444-3353.SKU 93793
produces chemicals known to the State
of California to cause cancer and birth
defects (or other reproductive harm).
(California Health & Safety Code §
25249.5, et seq.)
SAVE THESE INSTRUCTIONS
Grounding
NOTE:
This Welder requires the installation of a
3-Prong, 240 V~, polarized,
twistlock Power Cord Plug (not included).
NEMA conguration # L6-30 or equivalent
The Plug must be installed by a certied
electrician.
WARNING!
Improperly connecting the grounding
wire can result in the risk of electric shock.
Check with a qualied electrician if you are
in doubt as to whether the outlet is properly
grounded. Do not modify the power cord
plug used with the tool. Never remove the
grounding prong from the plug. Do not use
the tool if the power cord or plug is damaged.
If damaged, have it repaired by a service
facility before use. If the plug will not t the
outlet, have a proper outlet installed by a
qualied electrician.
GROUNDED TOOLS: TOOLS WITH
THREE PRONG PLUGS
Tools marked with “Grounding Required”1.
have a three wire cord and three prong
grounding plug. The plug must be
connected to a properly grounded outlet.
If the tool should electrically malfunction
or break down, grounding provides a
low resistance path to carry electricity
away from the user, reducing the risk of
electric shock.
The grounding prong in the plug is2.
connected through the green wire inside
the cord to the grounding system in the
tool. The green wire in the cord must
be the only wire connected to the tool’s
grounding system and must never be
attached to an electrically “live” terminal.
Your tool must be plugged into an3.
appropriate outlet, properly installed by
a certied electrician and grounded
in accordance with all codes and
ordinances.
Extension Cords
AN EXTENSION CORD MUST NEVER
BE USED WITH THIS ITEM. Use of
an extension cord could result in
damage to the item or re.
Symbology
Double Insulated
Canadian Standards Association
Underwriters Laboratories, Inc.
V~ Volts Alternating Current
AAmperes
n0xxxx/min. No Load Revolutions per Minute
(RPM)
UNPACKING
When unpacking both boxes, make
sure all the parts shown on the Parts Lists
on pages 29 through 31 are included. If
any parts are missing or broken, please call
Harbor Freight Tools at 1-800-444-3353 as
soon as possible.

Page 10For technical questions, please call 1-800-444-3353.SKU 93793
AXLE BRACKET (40)
AXLE (44)
WASHER (42)
COTTER PIN
(41)
AXLE BRACKET (40)
COTTER PIN
(41)
WASHER (42)
WHEEL (43)
CASTER (37)
BOTTOM PANEL (36)
BOLT
BOTTOM
VIEW
FIGURE B
ASSEMBLY INSTRUCTIONS
WARNING! Always turn off the Welder and unplug the unit from its electri-
cal outlet prior to performing any assembly, maintenance, or service.
To Attach The Handle
Insert the Handle (45) into the Right
Handle Socket (46) and Left Handle
Socket (58). Then attach the Right and
Left Handle Sockets to the Front Panel
(57), using the four Bolts provided.
(See Figure A.)
BOLT
BOLT
BOLT
BOLT
HANDLE (45)
RIGHT HAN-
DLE SOCKET
(46)
LEFT HAN-
DLE SOCKET
(46)
FIGURE A
To Install The Rear Wheels And Casters
Insert the two Axle Brackets (40) into the slots located at the rear of the Bottom Panel1.
(36). Secure the Axle Brackets to the Bottom Panel, using the two Screws provided.
Insert the Axle (44) through the openings (located on the underside of the Bottom Panel)
in the Axle Brackets. Insert one Wheel (43) on each end of the Axle. Insert one Washer
(42) on each end of the Axle. Then secure the two Wheels to the Axle, using one Cotter
Pin (41) on each end of the Axle. (See Figure B.)
Align the four mounting holes in each of the two Casters (37) with the threaded mounting2.
holes located at the front of the Bottom Panel (36). Then secure the two Casters to the
Bottom Panel, using the eight Bolts provided. (See Figure B.)