Chicago Electric MIG-100 User Manual

®

MIG-100 WELDERMIG-100 WELDER

MIG-100 WELDER

MIG-100 WELDERMIG-100 WELDER

WITH THERMAL OVERLOADWITH THERMAL OVERLOAD

WITH THERMAL OVERLOAD

WITH THERMAL OVERLOADWITH THERMAL OVERLOAD

91124

ASSEMBLY AND OPERATING INSTRUCTIONS

3491 Mission Oaks Blvd., Camarillo, CA 93011

Visit our Web site at http://www.harborfreight.com

Copyright© 2004 by Harbor F reight 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.

For technical questions and replacement parts, please call 1-800-444-3353.

REVISED 12/04

Specifications

ITEM DESCRIPTION

Welding Current 90 AMPs
Duty Cycle 10%@90AMPs
Power Consumption 110VAC, 23 amps
Heat Control Switch on Unit This model is not adjustable
Ground Cable 4 AWG, single insulation, 6 foot
Torch Power Cable 8 AWG, single insulation, 6 foot
Po wer Cord 3-core, double insulated, 14 AWG, U.L. approved
Power Cord Plug UL Approved
Thermal Overload
Welder Tip 0.030”; Spare: Welder Tip 0.035 inch;

Wire Size 0.030 inch flux core wire when using 0.030” Welder Tip
Wire Spool Size 4 inches diameter
Overall Dimensions 14-1/2 (L) x 8-1/2 (W) x 15-1/2 (H) inches
Weight 34.45 lbs.
Accessories Spare Welder Tip

Both settings: 10 min. shutdown, 3 min. back on with Light

Will also accept 0.023” welder tip

Welding F ace Shield
Wire Brush / Hammer combination

Save This Manual

You will need the manual for the safety warnings and precautions, assembly instructions,
operating and maintenance procedures, parts list and diagram. Keep your invoice with this
manual. Write the invoice number on the inside of the front cover. Keep the manual and
invoice in a safe and dry place for future reference.

Safety Warnings and Precautions

WARNING: When using tool, basic safety precautions should always be followed to
reduce the risk of personal injury and damage to equipment.

Read all instructions before using this tool!

1. Keep work area clean. Cluttered areas invite injuries.

2. Observe work area conditions. Do not use machines or power tools in damp or wet
locations. Don’t expose to rain. Keep work area well lighted. Do not use electrically
powered tools in the presence of flammable gases or liquids.

3. Keep children awa y. Children must ne v er be allow ed in the work area. Do not let them
handle machines, tools, or extension cords.

4. Store idle equipment. When not in use, tools must be stored in a dry location to inhibit
rust. Always lock up tools and k eep out of reach of children.

5. Do not force tool. It will do the job better and more safely at the rate for which it was
intended. Do not use inappropriate attachments in an attempt to e xceed the tool capacity .

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REV 06/04

6. Use the right tool for the job. Do not attempt to force a small tool or attachment to do
the work of a larger industrial tool. There are certain applications for which this tool was
designed. Do not modify this tool and do not use this tool for a purpose for which it was
not intended.

7. Dress properly. Do not wear loose clothing or jewelry as they can be caught in moving
parts. Protective, electrically nonconductive clothes and nonskid footwear are
recommended when working. Wear restrictive hair covering to contain long hair.

8. Use eye and ear protection. Always wear ANSI approved, arc shaded, impact safety
face shield. Always use the full face shield (provided) when arc welding. Wear an ANSI
approved dust mask or respirator when working around metal, chemical dusts, fumes
and mists.

9. Do not overreach. Keep proper footing and balance at all times. Do not reach over or
across running machines.

10. Maintain tools with care. Keep tools sharp and clean for better and saf er performance.
Follow instructions f or lubricating and changing accessories. Inspect tool cords periodically
and, if damaged, have them repaired b y an authorized technician. The handles must be
kept clean, dry, and free from oil and grease at all times.

11. Disconnect power. Unplug tool when not in use.

12. Remove adjusting keys and wrenches. Check that keys and adjusting wrenches are
removed from the tool or machine work surface before plugging it in.

13. Avoid unintentional starting. Be sure the s witch is in the Off position when not in use
and before plugging in. Do not carry any tool with y our finger on the trigger , whether it is
plugged in or not.

14. Stay alert. Watch what you are doing, use common sense. Do not operate any tool
when you are tired.

15. Check for damaged parts. Before using any tool, any part that appears damaged
should be carefully checked to determine that it will operate properly and perform its
intended function. Check f or alignment and binding of moving parts; an y broken parts or
mounting fixtures; and any other condition that may affect proper operation. Any par t
that is damaged should be properly repaired or replaced by a qualified technician. Do
not use the tool if any switch does not turn On and Off properly.

16. Guard against electric shock. Prevent body contact with grounded surfaces such as
pipes, radiators, ranges, and refrigerator enclosures.

17. Replacement parts and accessories. When servicing, use only identical replacement
parts. Use of any other parts will void the warranty. Only use accessories intended for
use with this tool. Approved accessories are available from Harbor Freight Tools.

18. Do not operate tool if under the influence of alcohol or drugs. Read warning labels
on prescriptions to determine if your judgment or reflexes are impaired while taking
drugs. If there is any doubt, do not operate the tool.

19. Maintenance. F or y our saf ety, service and maintenance should be performed regularly
by a qualified technician.

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20. Use proper size and type extension cord. If an e xtension cord is required, it must be of
the proper size and type to supply the correct current to the tool without heating up.
Otherwise, the extension cord could melt and catch fire, or cause electrical damage to
the tool. This tool requires use of an extension cord of 20 amps minimum capability (up
to 30 feet), with wire size rated at 12 AWG. Longer extension cords require larger size
wire. If you are using the tool outdoors, use an extension cord rated for outdoor use
(signified by “WA” on the jacket).

Note: Performance of this tool may vary depending on variations in local line voltage. Exten­sion cord usage may also affect tool performance.

Warning: The warnings, cautions, and instructions discussed in this instruction 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 .

Arc W elding Safety W arnings and Precautions

Warning: This product, when used for welding and similar applications, 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.

1. Avoid electrical shock. Do not permit electrically live par ts, cables, or electrodes to
contact skin, clothing, or gloves. Protective clothing should be hole-free, dry, and ANSI
approved.

This unit draws enough current to cause serious injury or death. Bef ore turning the welder

on, check the electrode holder to be sure that there are no protruding screw heads, and
that all insulation is secure. Do not weld unless you are insulated from ground and the
work piece.

2. Avoid breathing fumes or gases. They can cause serious health problems. Use an
active ventilation system directly above the welding area. Keep your head out of the
fumes.

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REV 05/04

3. Avoid eye and body damage. Arc rays and infrared radiation can injure ey es and burn
skin. Wear ANSI approved eye and body protection. Do not allow viewing by visitors
without proper eye and body protection. Use the provided Face Shield with arc shaded
filter plate.

4. Know proper arc welding practices. Read and understand the manufacturer’s
instructions, as well as your employer’s safety practices for arc welding.

5. Connect only to a code appro ved power sour ce. Connect only to a grounding power
source conforming to the National Electrical Code and Local Codes.

6. Avoid fire and explosion. Remove flammable and explosive material from at least 35
feet from the welding arc to pre v ent w elding sparks or molten metal from starting a fire.
Keep a type ABC fire e xtinguisher within easy reach. Thoroughly clean the object being
welded of any paint, grease, or other foreign material.

7. Av oid being burned. Always wear ANSI approv ed welding gear: leather glo ves, leather
apron, and shoes.

Unpacking

When unpacking, check to make sure the following parts are included.

Face Shield (38)

MIG-100 Welder

Torch (1)

Power Cord (32)

Ground Cable (33)

Wire Spool and Spare

Wire Brush / Hammer (39)

Welding Tip not shown here.

If any parts are missing or broken, please call Harbor Freight Tools at the number on the
cover of this manual as soon as possible.

Assembly

1. Attach the Handle (30) to the Cover (31) using screw (29) inserted from the Handle
top-rear. Refer to the photo at the top of page 6, and the Assembly Drawing on page

10.

2. Attach the Cover Locking Spring (8) to the front of the Base Frame (14) using the
supplied self-tapping screw.

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Cover Locking Spring (8)

Cover (31)

Handle (30)

Wire Reel (27)

Note:

What does the term “duty cycle mean?

Duty cycle is a welding equipment specification, which defines the number of minutes, within
a 10-minute period, during which a given welder can safely produce a particular welding
current. For example, this 90 amp welder with a 10% duty cycle must be rested for at least 9
minutes after 1 minute of continuous welding.

Failure to carefully observe duty cyc le limitations can easil y over stress a welder’s po wer
generation system contributing to premature welder failure. Many welders do not have
internal protection systems that prevent this sort of over stress -- leaving the task to the
owner or operator .

Operation

The MIG 100 Welder is used to weld sheet metal and light carbon steel.

Overload Indicator Light (22)
Switch (7) Current Min. / Max.*

Torch (1) Cable

Wire Feed Speed Knob (9)

Ground Cable (33)

Switch (7) Power On / Off

* NOTE: THIS UNIT IS
NOT ADJUSTABLE.

Power Cord (32)

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Caution: Before arc welding, read and understand all safety precautions and warnings
listed on pages 2 through 5.

1. Securely clamp the Ground Cable Clamp (33) as close as possible to the metal object
to be welded, or to the metal work bench where the object is mounted and electrically
connected.

2. This unit is not adjustable. Current switch is set at 90 AMPs.

3. Verify that the Power Switch is in the OFF position, then plug the MIG-100 Welder plug
into a dedicated, 110 VAC, 20 amp line with delayed action type circuit breaker or
fuses.

If an extension cord is used, it must have the following wire size: up to 30 feet, use 12

AWG size wire; 30 to 50 feet, use 10 AWG wire; Over 50 feet, use 8 AWG wire.

4. While holding the Torch Cable Clamp with electrode wire clearly out of the way of any
grounded objects, turn the Po wer Switch to the ON position.

5. Momentarily press the Torch switch to test the wire feed speed.

Adjust the speed by turning the Wire Feed Speed Knob

(9).

6. Orient yourself on the area to be welded, then place the
Face Shield over your eyes.

Warning: Never look at the ignited arc without ANSI appr oved,
arc shaded, eye protection in a full face shield. Permanent
eye damage or blindness can occur. Skin burns can occur.
Never breath arc fumes.

7. Press (and hold) the Torch button and stroke the area to be
welded with the electrode wire to ignite the arc.

Nev er tap the electrode wire into the welding surface to ignite the arc. This damages its

external coating on the electrode which prevents oxygen in the air from coming into
contact with the molten metal, causing it to oxidize.

8. Once the arc is ignited, tilt the electrode wire forward at an angle of approximately 35°.

The wire feeds automatically at a speed dependent on the Min. or Max. current setting.

Note: If too much current is dra wn from the MIG Welder, the Thermal Ov erload protector will
activate, the amber indicator will light, and the Arc W elder will turn off until it cools down. If this
happens, turn the Power Switch to the OFF position and wait about 3 ~ 5 minutes.

9. When the weld is complete, lift the electrode wire clearly away from any grounded
object, set the Face Shield down and turn toward the MIG-100 Welder and turn the
Power Switch to the OFF position.

10. Unplug the Power Cord from the electrical outlet.

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Maintenance

Caution: Bef ore performing any maintenance on the MIG Welder , unplug the Power Cor d
from the electrical outlet.

1. Periodically remove the Right and Left side panels (12 and 13), and using compressed
air, b lo w out all dust from the interior .

2. Store in a clean and dry location.

Replacing the Wire Reel

When the wire on the Feed Reel is used up, you will need to replace it as follows.

T ension Adjusting

Wire Feed Adjusting Spring (36)

Screw (37)

Wire Sheath

1. Press on the Cover Locking Spring (8), then lift the Cover (31) using Handle (30) to
expose the Wire Feed Unit (23).

2. Unscrew the Wing Nut (25) and remove the Reel Locking Knob (26).

3. Remove the empty Wire Reel (27).

4. Place the new Wire Reel over the shaft and onto the Reel Spring (24).

The wire on the reel should unwind counterclockwise

(see photo above).

5. Replace the Reel Locking Knob and the Wing Nut.
Tighten well.

6. Lift the Wire Feed Adjusting Spring (36) to remove
tension.

7. Guide at least 12 inches of wire into the Torch Sheath.

If the end of the wire is crimped or bent, cut it off.

8. Replace tension to the Wire Feed Adjusting Spring (36).

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9. Turn the Torch Handle Nozzle counterclockwise and pull to remove.

10. Turn the Contact Tip counterclockwise and remov e.

11. Lay the Torch Sheath out in a straight line so that the wire moves through it easily.

Warning: The following steps require applying power to the welder. Do not touch any­thing with the Tor ch Handle or an ar c ma y be ignited.

12. Plug the Po wer Cord into its electrical outlet, press the Current Switch to Max., and turn
the welder ON.

13. Lift the Torch Handle and continue pressing the Trigger until the wire feeds through two
inches.

If the wire does not feed, view the Wire Feed Unit and see if the wire is being pushed.

If it is not, turn the welder OFF and add more tension to the Wire Feed Adjusting
Spring (36).

14. Turn the welder ON again and press the Trigger.

15. Once the wire is exposed, turn the welder OFF and unplug it.

16. Slide the Contact Tip over the wire and screw it into Torch Handle.

17. Replace the Nozzle and cut off any excess wire over two inches.

18. Secure the Cover.

THE MANUF ACTURER AND/OR DISTRIBUT OR HAS PRO VIDED THE PARTS DIAGRAM IN THIS
MANUAL AS A REFERENCE TOOL ONLY . NEITHER THE MANUF ACTURER NOR DISTRIBUT OR
MAKES ANY REPRESENTA TION OR WARRANTY OF ANY KIND TO THE BUYER THA T HE OR
SHE IS QUALIFIED TO MAKE ANY REPAIRS TO THE PRODUCT OR THAT HE OR SHE IS
QUALIFIED TO REPLACE ANY PARTS OF THE PRODUCT. IN FACT, THE MANUFACTURER
AND/OR DISTRIBUTOR EXPRESSLY ST A TES T HA T ALL REP AIRS AND PARTS REPLACEMENTS
SHOULD BE UNDERTAKEN BY CERTIFIED AND LICENSED TECHNICIANS AND NOT BY THE
BUYER. THE BUYER ASSUMES ALL RISK AND LIABILITY ARISING OUT OF HIS OR HER
REPAIRS TO THE ORIGINAL PRODUCT OR REPLACEMENT PARTS THERETO, OR ARISING
OUT OF HIS OR HER INST ALLATION OF REPLACEMENT P ARTS THERET O.

PLEASE READ THE FOLLOWING CAREFULLY

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Welder Parts List

Item # Description Qty

1Torch 1
2 Contact Tip 1
3Nozzle 1
4Liner 1
5 Fixing Pole (A) for Gun Body 1
6 Fixing Pole (B) for Gun Body 1
7Switch 2
8 Cover Locking Spring 1
9Knob 1

10 Nut 1

11 Spe ed C ontrol Circuit Board 1
12 Right Side Panel 1
13 Left S ide Panel 1
14 Base Frame 1
15 Foot 4
16 Washer 4

Item # Description Qty

21 Middle Part i ti on Board 1
22 Overload Indicator Lamp 1
23 W ir e Feed Unit 1
24 Reel Spri ng 1
25 Wing Nut, M6 1
26 Reel Locking Knob 1
27 W ir e Reel 1
28 Reel Hol der 1
29 Self-t apping Scr ew, ST4. 2*25 1
30 Handle 1

31 Cover 1
32 Power Cord 1
33 Ground Cable 1
34 Wire Feed Roll er 1
35 Wire Feed Beari ng 1
36 Wir e Feed Adjusti ng Spring 1

17 Self -t ap ping Screw, ST4.2 *13 4
18 Tr ansformer Carriage 2
19 Thermostat 1
20 Transformer 1

37 Adj ustme nt Scr ew 1
38 Face S h ield 1
39 Wir e Brush / Hammer 1

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Welder Assembly Drawing

NOTE: Some parts are listed and shown for

illustration purposes only and are not avail­able individually as replacement parts.

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Welder Assembly Photographs

20

19

28

24

23

11

35

36 35

34

23

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Wiring Schematic

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