Lincoln arc welding and cutting
equipment is designed and built
with safety in mind. However, your
overall safety can be increased by
proper installation ... and thoughtful operation on your part.
NOT INSTALL, OPERATE OR
REPAIR THIS EQUIPMENT
WITHOUT READING THIS
MANUAL AND THE SAFETY
PRECAUTIONS CONTAINED
THROUGHOUT.
importantly, think before you act
and be careful.
And, most
DO
SP-125 PLUS
March, 2001
10260, 10481,10685,10689,10690,10740
Date of Purchase:
Serial Number:
Code Number:
Model:
Where Purchased:
Designed and Manufactured Under a
Quality Program Certified by
ABS Quality Evaluations, Inc.
Diesel engine exhaust and some of its constituents
are known to the State of California to cause cancer, birth defects, and other reproductive harm.
The Above For Diesel Engines
ARC WELDING CAN BE HAZARDOUS. PROTECT YOURSELF AND OTHERS FROM POSSIBLE SERIOUS INJURY OR DEATH.
KEEP CHILDREN AWAY. PACEMAKER WEARERS SHOULD CONSULT WITH THEIR DOCTOR BEFORE OPERATING.
Read and understand the following safety highlights. For additional safety information, it is strongly recommended that you
purchase a copy of “Safety in Welding & Cutting - ANSI Standard Z49.1” from the American Welding Society, P.O. Box
351040, Miami, Florida 33135 or CSA Standard W117.2-1974. A Free copy of “Arc Welding Safety” booklet E205 is available
from the Lincoln Electric Company, 22801 St. Clair Avenue, Cleveland, Ohio 44117-1199.
BE SURE THAT ALL INSTALLATION, OPERATION, MAINTENANCE AND REPAIR PROCEDURES ARE
PERFORMED ONLY BY QUALIFIED INDIVIDUALS.
The engine exhaust from this product contains
chemicals known to the State of California to cause
cancer, birth defects, or other reproductive harm.
The Above For Gasoline Engines
FOR ENGINE
powered equipment.
1.a. Turn the engine off before troubleshooting and maintenance
work unless the maintenance work requires it to be running.
1.c. Do not add the fuel near an open flame
welding arc or when the engine is running.
Stop the engine and allow it to cool before
refueling to prevent spilled fuel from vaporizing on contact with hot engine parts and
igniting. Do not spill fuel when filling tank. If
fuel is spilled, wipe it up and do not start
engine until fumes have been eliminated.
1.d. Keep all equipment safety guards, covers and devices in
position and in good repair.Keep hands, hair, clothing and
tools away from V-belts, gears, fans and all other moving
parts when starting, operating or repairing equipment.
1.e. In some cases it may be necessary to remove safety
guards to perform required maintenance. Remove
guards only when necessary and replace them when the
maintenance requiring their removal is complete.
Always use the greatest care when working near moving
parts.
1.f. Do not put your hands near the engine fan.
Do not attempt to override the governor or
idler by pushing on the throttle control rods
while the engine is running.
1.h. To avoid scalding, do not remove the
radiator pressure cap when the engine is
hot.
ELECTRIC AND
MAGNETIC FIELDS
may be dangerous
2.a. Electric current flowing through any conductor causes
localized Electric and Magnetic Fields (EMF). Welding
current creates EMF fields around welding cables and
welding machines
2.b. EMF fields may interfere with some pacemakers, and
welders having a pacemaker should consult their physician
before welding.
2.c. Exposure to EMF fields in welding may have other health
effects which are now not known.
2.d. All welders should use the following procedures in order to
minimize exposure to EMF fields from the welding circuit:
2.d.1.
Route the electrode and work cables together - Secure
them with tape when possible.
2.d.2. Never coil the electrode lead around your body.
2.d.3. Do not place your body between the electrode and
work cables. If the electrode cable is on your right
side, the work cable should also be on your right side.
1.g. To prevent accidentally starting gasoline engines while
turning the engine or welding generator during maintenance
work, disconnect the spark plug wires, distributor cap or
magneto wire as appropriate.
SP-125 PLUS
2.d.4. Connect the work cable to the workpiece as close as
possible to the area being welded.
2.d.5. Do not work next to welding power source.
Mar ‘95
ii
SAFETY
ii
ELECTRIC SHOCK can
kill.
3.a. The electrode and work (or ground) circuits
are electrically “hot” when the welder is on.
Do not touch these “hot” parts with your bare
skin or wet clothing. Wear dry, hole-free
gloves to insulate hands.
3.b. Insulate yourself from work and ground using dry insulation.
Make certain the insulation is large enough to cover your full
area of physical contact with work and ground.
In addition to the normal safety precautions, if welding
must be performed under electrically hazardous
conditions (in damp locations or while wearing wet
clothing; on metal structures such as floors, gratings or
scaffolds; when in cramped positions such as sitting,
kneeling or lying, if there is a high risk of unavoidable or
accidental contact with the workpiece or ground) use
the following equipment:
• Semiautomatic DC Constant Voltage (Wire) Welder.
• DC Manual (Stick) Welder.
• AC Welder with Reduced Voltage Control.
3.c. In semiautomatic or automatic wire welding, the electrode,
electrode reel, welding head, nozzle or semiautomatic
welding gun are also electrically “hot”.
3.d. Always be sure the work cable makes a good electrical
connection with the metal being welded. The connection
should be as close as possible to the area being welded.
3.e. Ground the work or metal to be welded to a good electrical
(earth) ground.
ARC RAYS can burn.
4.a. Use a shield with the proper filter and cover
plates to protect your eyes from sparks and
the rays of the arc when welding or observing
open arc welding. Headshield and filter lens
should conform to ANSI Z87. I standards.
4.b. Use suitable clothing made from durable flame-resistant
material to protect your skin and that of your helpers from
the arc rays.
4.c. Protect other nearby personnel with suitable, non-flammable
screening and/or warn them not to watch the arc nor expose
themselves to the arc rays or to hot spatter or metal.
FUMES AND GASES
can be dangerous.
5.a. Welding may produce fumes and gases
hazardous to health. Avoid breathing these
fumes and gases.When welding, keep
your head out of the fume. Use enough
ventilation and/or exhaust at the arc to keep
fumes and gases away from the breathing zone. When
welding with electrodes which require special
ventilation such as stainless or hard facing (see
instructions on container or MSDS) or on lead or
cadmium plated steel and other metals or coatings
which produce highly toxic fumes, keep exposure as
low as possible and below Threshold Limit Values (TLV)
using local exhaust or mechanical ventilation. In
confined spaces or in some circumstances, outdoors, a
respirator may be required. Additional precautions are
also required when welding on galvanized steel.
3.f.
Maintain the electrode holder, work clamp, welding cable and
welding machine in good, safe operating condition. Replace
damaged insulation.
3.g. Never dip the electrode in water for cooling.
3.h. Never simultaneously touch electrically “hot” parts of
electrode holders connected to two welders because voltage
between the two can be the total of the open circuit voltage
of both welders.
3.i. When working above floor level, use a safety belt to protect
yourself from a fall should you get a shock.
3.j. Also see Items 6.c. and 8.
5.b.
Do not weld in locations near chlorinated hydrocarbon
coming from degreasing, cleaning or spraying operations.
The heat and rays of the arc can react with solvent vapors
form phosgene, a highly toxic gas, and other irritating
products.
5.c. Shielding gases used for arc welding can displace air and
cause injury or death. Always use enough ventilation,
especially in confined areas, to insure breathing air is safe.
5.d. Read and understand the manufacturer’s instructions for this
equipment and the consumables to be used, including the
material safety data sheet (MSDS) and follow your
employer’s safety practices. MSDS forms are available from
your welding distributor or from the manufacturer.
5.e. Also see item 1.b.
Mar ‘95
vapors
to
SP-125 PLUS
iii
SAFETY
iii
WELDING SPARKS can
cause fire or explosion.
6.a.
Remove fire hazards from the welding area.
If this is not possible, cover them to prevent
the welding sparks from starting a fire.
materials from welding can easily go through small cracks
and openings to adjacent areas. Avoid welding near
hydraulic lines. Have a fire extinguisher readily available.
6.b. Where compressed gases are to be used at the job site,
special precautions should be used to prevent hazardous
situations. Refer to “Safety in Welding and Cutting” (ANSI
Standard Z49.1) and the operating information for the
equipment being used.
6.c. When not welding, make certain no part of the electrode
circuit is touching the work or ground. Accidental contact
can cause overheating and create a fire hazard.
6.d. Do not heat, cut or weld tanks, drums or containers until the
proper steps have been taken to insure that such procedures
will not cause flammable or toxic vapors from substances
inside. They can cause an explosion even
been “cleaned”. For information, purchase “Recommended
Safe Practices for the
Containers and Piping That Have Held Hazardous
Substances”, AWS F4.1 from the American Welding Society
(see address above).
6.e. Vent hollow castings or containers before heating, cutting or
welding. They may explode.
Sparks and spatter are thrown from the welding arc. Wear oil
6.f.
free protective garments such as leather gloves, heavy shirt,
cuffless trousers, high shoes and a cap over your hair. Wear
ear plugs when welding out of position or in confined places.
Always wear safety glasses with side shields when in a
welding area.
6.g. Connect the work cable to the work as close to the welding
area as practical. Work cables connected to the building
framework or other locations away from the welding area
increase the possibility of the welding current passing
through lifting chains, crane cables or other alternate circuits. This can create fire hazards or overheat lifting chains
or cables until they fail.
6.h. Also see item 1.c.
Remember that welding sparks and hot
though
they have
Preparation
for Welding and Cutting of
CYLINDER may explode
if damaged.
7.a. Use only compressed gas cylinders
containing the correct shielding gas for the
process used and properly operating
regulators designed for the gas and
pressure used. All hoses, fittings, etc. should be suitable for
the application and maintained in good condition.
7.b. Always keep cylinders in an upright position securely
chained to an undercarriage or fixed support.
7.c. Cylinders should be located:
• Away from areas where they may be struck or subjected to
physical damage.
• A safe distance from arc welding or cutting operations and
any other source of heat, sparks, or flame.
7.d. Never allow the electrode, electrode holder or any other
electrically “hot” parts to touch a cylinder.
7.e. Keep your head and face away from the cylinder valve outlet
when opening the cylinder valve.
7.f. Valve protection caps should always be in place and hand
tight except when the cylinder is in use or connected for
use.
7.g. Read and follow the instructions on compressed gas
cylinders, associated equipment, and CGA publication P-l,
“Precautions for Safe Handling of Compressed Gases in
Cylinders,” available from the Compressed Gas Association
1235 Jefferson Davis Highway, Arlington, VA 22202.
FOR ELECTRICALLY
powered equipment.
8.a. Turn off input power using the disconnect
switch at the fuse box before working on
the equipment.
8.b. Install equipment in accordance with the U.S. National
Electrical Code, all local codes and the manufacturer’s
recommendations.
8.c. Ground the equipment in accordance with the U.S. National
Electrical Code and the manufacturer’s recommendations.
Mar ‘95
SP-125 PLUS
iv
SAFETY
iv
PRÉCAUTIONS DE SÛRETÉ
Pour
votre propre protection lire et observer toutes les instructions
et les précautions de sûreté specifiques qui parraissent dans ce
manuel aussi bien que les précautions de sûreté générales suivantes:
Sûreté Pour Soudage A L’Arc
1. Protegez-vous contre la secousse électrique:
a. Les circuits à l’électrode et à la piéce sont sous tension
quand la machine à souder est en marche. Eviter toujours
tout contact entre les parties sous tension et la peau nue
ou les vétements mouillés. Porter des gants secs et sans
trous pour isoler les mains.
b. Faire trés attention de bien s’isoler de la masse quand on
soude dans des endroits humides, ou sur un plancher
metallique ou des grilles metalliques, principalement dans
les positions assis ou couché pour lesquelles une grande
partie du corps peut être en contact avec la masse.
c. Maintenir le porte-électrode, la pince de masse, le câble
de soudage et la machine à souder en bon et sûr état
defonctionnement.
d.Ne jamais plonger le porte-électrode dans l’eau pour le
refroidir.
e. Ne jamais toucher simultanément les parties sous tension
des porte-électrodes connectés à deux machines à souder
parce que la tension entre les deux pinces peut être le
total de la tension à vide des deux machines.
f. Si on utilise la machine à souder comme une source de
courant pour soudage semi-automatique, ces precautions
pour le porte-électrode s’applicuent aussi au pistolet de
soudage.
zones où l’on pique le laitier.
6. Eloigner les matériaux inflammables ou les recouvrir afin de
prévenir tout risque d’incendie dû aux étincelles.
7. Quand on ne soud
la masse. Un court-circuit accidental peut provoquer un
échauffement et un risque d’incendie.
8. S’assurer que la masse est connectée le plus prés possible
de la zone de travail qu’il est pratique de le faire. Si on place
la masse sur la charpente de la construction ou d’autres
endroits éloignés de la zone de travail, on augmente le risque
de voir passer le courant de soudage par les chaines de levage, câbles de grue, ou autres circuits. Cela peut provoquer
des risques d’incendie ou d’echauffement des chaines et des
câbles jusqu’à ce qu’ils se rompent.
9. Assurer une ventilation suffisante dans la zone de soudage.
Ceci est particuliérement important pour le soudage de tôles
galvanisées plombées, ou cadmiées ou tout autre métal qui
produit des fumeés toxiques.
10. Ne pas souder en présence de vapeurs de chlore provenant
d’opérations de dégraissage, nettoyage ou pistolage. La
chaleur ou les rayons de l’arc peuvent réagir avec les vapeurs
du solvant pour produire du phosgéne (gas fortement toxique)
ou autres produits irritants.
11. Pour obtenir de plus amples renseignements sur la sûreté,
voir le code “Code for safety in welding and cutting” CSA
Standard W 117.2-1974.
e pas, poser la pince à une endroit isolé de
2. Dans le cas de travail au dessus du niveau du sol, se protéger
contre les chutes dans le cas ou on recoit un choc. Ne jamais
enrouler le câble-électrode autour de n’importe quelle partie
du corps.
3. Un coup d’arc peut être plus sévère qu’un coup de soliel,
donc:
a. Utiliser un bon masque avec un verre filtrant approprié
ainsi qu’un verre blanc afin de se protéger les yeux du rayonnement de l’arc et des projections quand on soude ou
quand on regarde l’arc.
b. Porter des vêtements convenables afin de protéger la
peau de soudeur et des aides contre le rayonnement de
l‘arc.
c. Protéger l’autre personnel travaillant à proximité au
soudage à l’aide d’écrans appropriés et non-inflammables.
4. Des gouttes de laitier en fusion sont émises de l’arc de
soudage. Se protéger avec des vêtements de protection libres
de l’huile, tels que les gants en cuir, chemise épaisse, pantalons sans revers, et chaussures montantes.
5. Toujours porter des lunettes de sécurité dans la zone de
soudage. Utiliser des lunettes avec écrans lateraux dans les
PRÉCAUTIONS DE SÛRETÉ POUR
LES MACHINES À SOUDER À
TRANSFORMATEUR ET À
REDRESSEUR
1. Relier à la terre le chassis du poste conformement au code de
l’électricité et aux recommendations du fabricant. Le dispositif
de montage ou la piece à souder doit être branché à une
bonne mise à la terre.
2. Autant que possible, I’installation et l’entretien du poste seront
effectués par un électricien qualifié.
3. Avant de faires des travaux à l’interieur de poste, la debrancher à l’interrupteur à la boite de fusibles.
4. Garder tous les couvercles et dispositifs de sûreté à leur
place.
Mar. ‘93
SP-125 PLUS
Thank You
vv
for selecting a QUALITY product by Lincoln Electric. We want you
to take pride in operating this Lincoln Electric Company product
••• as much pride as we have in bringing this product to you!
Please Examine Carton
When this equipment is shipped, title passes to the purchaser upon receipt by the carrier. Consequently, Claims
for material damaged in shipment must be made by the purchaser against the transportation company at the
time the shipment is received.
Please record your equipment identification information below for future reference. This information can be
found on your machine nameplate.
Model Name & Number _____________________________________
Code & Serial Number _____________________________________
Date of Purchase _____________________________________
Whenever you request replacement parts for or information on this equipment always supply the information
you have recorded above.
Read this Operators Manual completely before attempting to use this equipment. Save this manual and keep it
handy for quick reference. Pay particular attention to the safety instructions we have provided for your protection.
The level of seriousness to be applied to each is explained below:
and Equipment For Damage Immediately
WARNING
This statement appears where the information must be followed exactly to avoid serious personal injury or
loss of life.
CAUTION
This statement appears where the information must be followed to avoid minor personal injury or damage to
this equipment.
SP-125 PLUS
v
TABLE OF CONTENTS
Page
Installation .......................................................................................................Section A
12.0 in9.75 in16.5 in54 Ibs
305 mm248 mm419 mm24.3 kg
.
SP-125 PLUS
A-2
1
2
3
4
5
W
ELD
IN
G
A
M
P
R
A
N
G
E
2
5-1
2
5
6
7
INSTALLATION
Read entire installation section before starting
installation.
SAFETY PRECAUTIONS
WARNING
ELECTRIC SHOCK can kill.
• Only qualified personnel should perform
this installation.
• Only personnel that have read and understood the SP-125 Plus Operating Manual
should install and operate this equipment.
• Machine must be plugged into a receptacle
which is grounded per any national, local
or other applicable electrical codes.
• The SP-125 Plus power switch is to be in
the OFF (“O”) position when installing
work cable and gun and when connecting
power cord to input power.
FIGURE A.1
W
EL
D
IN
G
2
AM
P
5-1
R
AN
25
G
E
IDENTIFY AND LOCATE
COMPONENTS
If you have not already done so, unpack the SP-125
Plus from its carton and remove all packing material
around the SP-125 Plus. Remove the following loose
items from the carton (see Figure A.1):
1. SP-125 Plus
2. Gun and cable assembly
3. Literature and miscellaneous including:
a) This operating manual
b) A contact tip for .030” (0.8 mm) diameter wire.
4. 10 ft (3.0 m) work cable.
5. Work clamp.
6. Sample Spool of L-56 .025 MIG Wire.
7. Adjustable mixed-Gas Regulator & Hose.
(1)
For available options and accessories refer to the
accessories section later in this manual.
1)
As shipped from the factory, the SP-125 Plus gun is
ready to feed .023 or .025 (0.6 mm) wire.
SP-125 PLUS
INSTALLATION
4
5
8
3
7
6
1
2
SP-125 Plus
WELDING AMP RANGE
25-125
+
-
9
A-3
SELECT SUITABLE LOCATION
Locate the welder in a dry location where there is free
circulation of clean air into the louvers in the back and
out the front of the unit. A location that minimizes the
amount of smoke and dirt drawn into the rear louvers
reduces the chance of dirt accumulation that can block
air passages and cause overheating.
STACKING
SP-125 Plus’ cannot be stacked.
TILTING
Each machine must be placed on a secure, level surface, either directly or on a recommended undercarriage. The machine may topple over if this procedure
is not followed.
OUTPUT CONNECTIONS
Refer to Figure A.2.
Work Clamp Installation
Attach the work clamp per the following:
1. Unplug the machine or turn the power switch to the
“OFF” position.
2. Insert the work cable terminal lug with the larger
hole through the strain relief hole in the work clamp
as shown in Figure A-3.
3. Fasten securely with the bolt and nut provided.
FIGURE A.3
Strain Relief Hole
Work Cable
Work Clamp
Nut & Bolt
1. Work Cable Access Hole.
2. Gun Cable and Control Lead Access Hole.
3. Connector Block.
4. Gun Trigger Lead Connectors.
5. Positive (+) and negative (–) output terminals.
6. Wire Feed Gearbox and Gun Connector Block
7. Cable Clamp
8. Thumbscrew - Secures gun and cable assembly
9. Optional Spot/Stitch Timer Kit see Accessories.
WELDING AMP RANGE
Work Cable Installation
Refer to Figure A.2.
1. Open the wire feed section door on the right side of
2. Pass the end of the work cable that has the termi-
FIGURE A.2
the SP-125 Plus.
nal lug with the smaller hole through the Work
Cable Access Hole (1) in the case front.
4
SP-125 PLUS
A-4
INSTALLATION
3. Route the cable under and around the back of the
Wire Feed Gearbox (6).
4. For GMAW Only: Refer to Figure A.2. As deliv-
ered, the SP-125 Plus is wired for positive polarity.
This is the appropriate configuration for the Gas
Metal Arc Welding (GMAW) process. To complete
installation, use the provided wing nut to connect
the work cable’s terminal lug to the negative (–)
output terminal (5) located above the Wire Feed
Gearbox (6). Make sure that both wing nuts are
tight.
5. For Innershield Only: Refer to Figure A.4. To wire
for negative polarity, connect the short cable
attached to the connector block (1) to the negative
(–) output terminal (2) and the work cable (3) to the
positive (+) terminal (4).
FIGURE A.4
4
3
2
1
3. Insert the connector on the gun conductor cable
through the Gun Cable Access Hole (2) in the SP125 Plus case front. Make sure the connector is all
the way in the metal connector block to obtain
proper gas flow. Rotate the connector so control
leads are on the underside and tighten the
Thumbscrew (8) in the connector block.
4. Connect the gun trigger control lead terminals to
the two insulated 1/4" (6,4 mm) tab connector
bushings located above the “Gun Trigger
Connection” decal in the wire feed section (4).
Either lead can go to either connector. Form the
leads so that they are as close as possible to the
inside panel.
CAUTION
If the gun trigger switch being used is other than
that supplied with the SP-125 Plus, the switch
must be a normally open, momentary switch. The
terminals of the switch must be insulated from the
welding circuit. Malfunction of the SP-125 Plus will
result if this switch shorts to the SP-125 Plus
welding output circuit or is common to any electrical circuit other than the SP-125 Plus trigger
circuit.
GUN INSTALLATION
As shipped from the factory, the SP-125 Plus gun is
ready to feed 0.023 - 0.025” (0,6 mm) wire. If 0.030”
(0,8 mm) wire is to be used install the 0.030” (0.8 mm)
contact tip. Refer to the MAINTENANCE section for
contact tip installation details.
Connecting Gun Cable to the SP-125 Plus
1. Refer to Figure A.2. Unplug the machine or turn
power switch to the off “O” position.
2. Pass the insulated terminals of the gun trigger control leads, one at a time, through the Gun Cable
and Control Lead Access Slot (2) in the case front.
The leads are to be routed under the Wire Feed
Gearbox (6) and through the Cable Hanger (7) on
the inner panel.
GAS CONNECTION
Refer to Figure A.5
When using the GMAW process, a cylinder of shielding gas, must be obtained. For more information about
selecting gas cylinders for use with the SP-125 Plus,
refer to the ACCESSORIES section.
WARNING
CYLINDER may explode if damaged. Keep cylinder upright and
chained to support
• Keep cylinder away from areas
where it may be damaged.
• Never lift welder with cylinder
attached.
• Never allow welding electrode to
touch cylinder.
• Keep cylinder away from welding
or other live electrical circuits.
SP-125 PLUS
INSTALLATION
A-5
WARNING
BUILDUP OF SHIELDING GAS may
harm health or kill.
• Shut off shielding gas supply
when not in use.
• SEE AMERICAN NATIONAL
STANDARD Z-49.1, “SAFETY IN
WELDING AND CUTTING” PUBLISHED BY THE AMERICAN
WELDING SOCIETY.
1. Chain the cylinder to a wall or other stationary support to prevent the cylinder from falling over.
Insulate the cylinder from the work circuit and earth
ground.
FIGURE A.5
Flow Regulator
Cylinder Valve
3. Attach the flow regulator to the cylinder valve and
tighten the union nut securely with a wrench. The
flow regulator for carbon dioxide must have a plastic washer seated in the fitting that attaches to the
cylinder to prevent leakage. Refer to K1800-1 in
the accessories section.
4. Refer to Figure A.6. Attach one end of inlet gas
hose to the outlet fitting of the flow regulator and
tighten the union nut securely with a wrench.
Connect the other end to the SP-125 Plus Gas
Solenoid Inlet Fitting (5/8-18 female threads — for
CGA — 032 fitting). Make certain the gas hose is
not kinked or twisted.
INPUT CONNECTIONS
Refer to Figure A.6.
The SP-125 Plus has two input connections, the
power input cable, and the Gas Solenoid Inlet Fitting.
Both are located on the rear of the machine.
Gas Hose
2. With the cylinder securely installed, remove the
cylinder cap. Stand to one side away from the outlet and open the cylinder valve very slightly for an
instant. This blows away any dust or dirt which may
have accumulated in the valve outlet.
WARNING
BE SURE TO KEEP YOUR FACE AWAY FROM THE
VALVE OUTLET WHEN “CRACKING” THE VALVE.
Never stand directly in front of or behind the flow
regulator when opening the cylinder valve. Always
stand to one side.
FIGURE A.6
Gas Solenoid
Inlet Fitting
Power
Input
Cable
SP-125 PLUS
A-6
INSTALLATION
CODE REQUIREMENTS FOR INPUT
CONNECTIONS
WARNING
This welding machine must be connected to
power source in accordance with applicable electrical codes.
The United States National Electrical Code (Article
630-B, 1990 Edition) provides standards for amperage
handling capability of supply conductors based on
duty cycle of the welding source.
If there is any question about the installation meeting
applicable electrical code requirements, consult a
qualified electrician.
Requirements For Rated Output
A power cord with a 15 amp, 125 volt, three prong
plug (NEMA Type 5-15P) is factory installed on the
SP-125 Plus. Connect this plug to a mating grounded
receptacle which is connected to a 20 amp branch circuit with a nominal voltage rating of 115 to 125 volts,
60 Hertz, AC only.
Requirements For CSA Rated Output
A line cord with a 15 amp, 125 volt, three-prong plug
(NEMA Type 5-15P) is factory installed. Connect this
plug to a mating grounded receptacle which is connected to a 15 amp branch circuit with a nominal voltage rating of 115 volts to 125 volts, 60 hertz, AC only.
With this installation, the SP-125 Plus can be used at
an output of 63 amps, 20 volts, 20% duty cycle.
The rated output with this installation is 90 amps, 18
Volts, 20% duty cycle (2 minutes of every 10 minutes
used for welding).
CAUTION
Do not connect the SP-125 Plus to an input power
supply with a rated voltage that is greater than 125
volts.
Do not remove the power cord ground prong.
Requirements For Maximum Output
In order to utilize the maximum output capability of the
machine, a branch circuit capable of 25 amps at 115
to 125 volts, 60 Hertz is required. This generally
applies when welding steel that is equal to or greater
than 12 gauge, 0.105” (2.5 mm) in thickness.
SP-125 PLUS
OPERATION
Read entire Operation section before
operating the SP-125 Plus.
WARNING
ELECTRIC SHOCK can kill.
• Do not touch electrically live
parts or electrode with skin or
wet clothing. Insulate yourself
from work and ground.
• Always wear dry insulating
gloves.
FUMES AND GASES can be
dangerous.
• Keep your head out of fumes.
• Use ventilation or exhaust to
remove fumes from breathing
zone.
B-1
WELDING SPARKS can
cause fire or explosion.
• Keep flammable material away.
• Do not weld on closed containers.
ARC RAYS can burn eyes
and skin.
• Wear eye, ear and body protection.
Observe all safety information throughout
this manual.
SP-125 PLUS
B-2
OFF
ON
ARC VOLTS
WIRE SPEED
OPERATION
GENERAL DESCRIPTION
The SP-125 Plus is a complete semiautomatic constant voltage DC arc welding machine. Included is a
solid state controlled, single phase constant voltage
transformer/ rectifier power source and a wire feeder
for feeding solid steel electrode and cored electrode.
The SP-125 Plus is ideally suited for individuals having access to 115 volt AC input power, and wanting
the ease of use, quality and dependability of both gas
metal arc welding or GMAW (also known as MIG
welding) and the Innershield electrode process (self
shielded flux cored or FCAW). The SP-125 Plus is a
rugged and reliable machine that has been designed
for dependable service and long life.
RECOMMENDED PROCESSES
The SP-125 Plus can be used for welding mild steel
using the GMAW, single pass, process which requires
a supply of shielding gas or it can be used for the self
shielded, Innershield electrode process (FCAW). The
SP-125 Plus is configured for use with the GMAW
(MIG) process as delivered from the factory.
● Reversible, dual groove drive roll. Drive roll will
feed .023-.035” (0.6- 0.9 mm) diameter wire.
● Accommodates both 8” (200 mm) diameter and 4”
(100 mm) diameter spools of wire.
● No external shielding gas is required when used
with Lincoln Innershield .035” (0,9 mm) NR®-211MP electrode.
● Easy to change polarity.
● Accepts optional Spot/Stitch Timer Kit.
WELDING CAPABILITY
The SP-125 Plus, as shipped, is rated at 90 amps, 18
volts, at 20% duty cycle on a ten minute basis. It is
capable of higher duty cycles at lower output currents.
LIMITATIONS
Arc Gouging cannot be performed with the SP-125
Plus. The SP-125 Plus is not recommended for pipe
thawing.
CONTROLS AND SETTINGS
OPERATIONAL FEATURES AND
CONTROLS
The SP-125 Plus has the following controls as standard: Power ON/OFF Switch, Voltage Control, Wire
Speed Control, and a Circuit Breaker.
DESIGN FEATURES AND
ADVANTAGES
● Operates on 115 volt input — no special wiring
required.
● Solid state output control.
● “Cold electrode” until gun trigger is pressed for an
added measure of safety.
● Overload protection — incorporates both a thermo-
stat and a circuit breaker.
● Quality wire drive with electronic overload protec-
tion.
● Easy-to-set continuous range controls for precise
setting of arc voltage and wire speed.
● Continuous voltage control.
● “Quick Release” idle roll pressure arm is easily
adjusted.
Refer to Figures B.1a & B.1b.
1. Power ON/OFF Switch —
When the power is on the
fan motor will run and air will
be exhausted out the louvers
in the front of the machine.
The welding output and wire
feeder remain off until the
gun trigger is pressed.
2. Voltage Control — A continuous control that gives full
range adjustment of power
source output voltage.
Voltage can be adjusted
while welding.
3. Wire Speed Control —
Controls the wire feed speed
from 50 – 400 in /min (1.3 –
10 m/min). The control can
be preset on the dial to the
setting specified on the SP125 Plus Application Chart
located on the inside of the
wire feed section door. Wire
speed is not affected when
changes are made in the
voltage control.
ON
ARC VOLTS
SP-125 PLUS
SP-125 PLUS
OPERATION
1
SP-125 Plus
WELDING AMP RANGE
25-125
3
2
4
5
1
FIGURE B.1a
Refer to Figure B.1b
4. Circuit Breaker – Protects machine from damage if
maximum output is exceeded. Button will extend
out when tripped (Manual reset).
5. Optional K695-2 Spot/Stitch Controls (see ACCESSORIES section) - If present, replaces Blank Panel
Assembly located on the center panel inside the
case door:
Mode Switch - Selects between Spot, Stitch, or
Seam (normal welding) mode. Spot mode welds for
an adjustable length of time (set by Time Control;
see below) and then stops, whenever the gun trigger is depressed and held. Stitch mode cycles
between welding and not welding for an adjustable
length of time (also set by Time Control) while the
gun trigger is depressed. In Seam mode the
machine will weld continuously while the gun trigger is depressed. Releasing the gun trigger in any
of the three modes will interrupt welding immediately.
Time Control - In Spot mode, controls spot mode
ON time between approximately .25 and 4.0 seconds. In Stitch mode, controls stitch mode ON time
and OFF time simultaneously between .25 and 4.0
seconds each. This control is deactivated while in
Seam mode.
FIGURE B.1b
B-3
WELDING OPERATIONS
SEQUENCE OF OPERATION
Wire Loading
Refer to Figure B.2 AND B3.
The machine power switch should be turned to the
OFF (“O”) position before working inside the wire feed
enclosure.
The machine is shipped from the factory ready to feed
4” (100 mm) diameter spools. A 4" (100 mm) diameter
spool is mounted directly on the 5/8" (16 mm) diameter spindle that has a built-in adjustable friction brake
to prevent overrun of the spool and excess slack in
the wire. The wing nut at the end of the shaft is used
to adjust the tension on the wire spool (See B.3 on the
following page).
To use 8" (200 mm) diameter spools, the 2" (51 mm)
diameter M15445 spindle must be used. Remove the
spacer and wing nut at the end of the shaft. Insert
spindle as shown in figure B.2. Reattach spacer and
wing nut.
Note:When loading and removing the 8” Spools
sure that the wing nut (inside the wire spool spindle
hub) is turned 90° from the wire spool spindle locking
tab. If the wing nut is positioned in line with the locking
tab, the tab cannot be depressed to load or unload the
wire spool.
Make certain the start end of the wire, which may protrude through the side of the spool, does not contact
any metallic case parts.
FIGURE B.2
Optional
Wire Spool Spindle
Locking Tab
8” Wire Spool
make
Be sure that this stud engages
the hole in the wire spool.
+
-
To wire drive
Wire Spool must be pushed all the way on the spindle so that the
spindle’s tab will hold it in place. The Wire Spool must rotate clockwise when wire is dereeled.
SP-125 PLUS
B-4
OPERATION
FIGURE B.3
Wire Spindle Shaft
To wire drive
Note: The brake should be adjusted with a spool of
wire installed. When properly adjusted it should
move freely but not coast.
Friction Brake Adjustments
1. With wire spool installed, check free movement
and coast of the spool.
2. To tighten the brake turn the wing nut clockwise in
1/4 turn increments until coasting stops.
3. To loosen the brake turn the wing nut counterclockwise in 1/4 turn increments until the wire
spool moves freely without coasting.
4" Wire Spool
Wing Nut
and Spacer
FIGURE B.4
2
1
5
3
6. The idle roll pressure adjustment wing nut is normally set for mid-position on the pressure arm
threads. If feeding problems occur because the
wire is flattened excessively, turn the pressure
adjustment counter-clockwise to reduce distortion
of the wire. Slightly less pressure may be required
when using 0.023 – 0.025” (0,6 mm) wire. If the
drive roll slips while feeding wire, the pressure
should be increased until the wire feeds properly.
4
The Wire Drive Feed Roll can
accommodate two wire sizes by
flipping the wire drive feed roll
over. The sizes are stenciled on
the drive roll.
Wire Threading
Refer to Figure B.4
1. Release the Spring Loaded Pressure Arm (1)
rotate the Idle Roll Arm (2) away from the Wire
Feed Drive Roll (3). Ensure that the visible, stenciled size on the drive roll matches the wire size
being used.
2. Carefully detach the end of the wire from the
spool. To prevent the spool from unwinding, do
not release the wire until after step 5.
3. Cut the bent portion of wire off and straighten the
first 4” (100 mm).
4. Thread the wire through the In-going guide tube
(4), over the drive roll (3), and into the out-going
guide tube (5).
5. Close the idle roll arm and latch the spring loaded
pressure arm (2) in place (now you may release
the welding wire).
WARNING
When inching the welding wire, the drive rolls, the
gun connector block and the gun contact tip are
always energized relative to work and ground and
remain energized several seconds after the gun
trigger is released.
7. Refer to Figure B.5. Remove gas nozzle and contact tip from end of gun.
8. Turn the SP-125 Plus ON (“I”).
9. Straighten the gun cable assembly.
10. Depress the gun trigger switch and feed welding
wire through the gun and cable. (Point gun away
from yourself and others while feeding wire.)
Release gun trigger after wire appears at end of
gun.
11. Replace contact tip and gas nozzle.
12. Refer to Figure B-6. Cut the wire off 1/4” – 3/8”
(6 – 10 mm) from the end of the tip. The SP-125
Plus is now ready to weld.
SP-125 PLUS
OPERATION
SP-125
Plus
B-5
FIGURE B.6FIGURE B.5
Gun Handle
Gas Diffuser
Contact Tip
Gas Nozzle
Shielding Gas
When using the GMAW process, a cylinder of shielding gas, must be obtained. Refer to the ACCESSORIES section for more information about selecting
gas cylinders for use with the SP-125 Plus.
1. For CO
, open the cylinder very slowly. For argon-
2
mixed gas, open cylinder valve slowly a fraction of
a turn. When the cylinder pressure gauge pointer
stops moving, open the valve fully.
2. If using a regulator with an adjustable flow meter,
close the gun trigger and adjust the flow to give 15
– 20 cubic ft per hour (CFH) (7 – 10 I/min) [use 20
-– 25 CFH (10 – 12 I/min) when welding out of
position or in a drafty location for CO
]. For argon
2
mixed gas, trigger to release gas pressure, and
turn off the adjust the flow to give 25 – 30 CFH
(12 – 14 I/min).
Contact Tip
Wire Electrode
3/8" – 1/2" Electrical Stickout
4. Check that the polarity is correct for the welding
wire being used and that the gas supply, if
required, is turned on.
5. When using Innershield electrode, remove the gas
nozzle and install the gasless nozzle. This will
improve visibility of the arc and protect the gas diffuser from weld spatter. Refer to the MAINTENANCE section for details on nozzle replacement.
6. Refer to Figure B.7. Connect work clamp to metal
to be welded. Work clamp must make good electrical contact to the workpiece. The workpiece
must also be grounded as stated in “Arc Welding
Safety Precautions” in the beginning of this manual.
7. Position gun over joint. End of wire may be lightly
touching the work.
3. Keep the cylinder valve closed, except when using
the SP-125 Plus. When finished welding:
a) Close the cylinder valve to stop gas flow.
b) Depress the gun trigger briefly to release the
pressure in the gas hose.
c) Turn off the SP-125 Plus.
Making A Weld
1. See Recommended Processes And Equipment
section for selection of welding wire and shielding
gas and for range of metal thicknesses that can be
welded.
2. See the Application Chart on the inside of wire
feed section door for information on setting the
SP-125 Plus controls.
3. Set the Voltage (“V”) and Wire Speed (“olo’”) controls to the settings suggested for the welding wire
and base metal thickness being used.
8. Lower welding helmet, close gun trigger, and
begin welding. Hold the gun so the contact tip to
work distance is about 3/8 inch (10 mm).
FIGURE B.7
SP-125 Plus
GUN CABLE
WORKPIECE
ARC
WORK CLAMP
SP-125 PLUS
B-6
OPERATION
9. To stop welding, release the gun trigger and then
pull the gun away from the work after the arc goes
out.
10. When no more welding is to be done, close valve
on gas cylinder (if used), momentarily operate gun
trigger to release gas pressure, and turn off the
SP-125 Plus.
Cleaning Tip And Nozzle
Clean the contact tip and nozzle to avoid arc bridging
between the nozzle and contact tip which can result in
a shorted nozzle, poor welds and an overheated gun.
Hint: Anti-stick spray or gel, available from a welding
supply distributor, may reduce buildup and aid in spatter removal.
PROCESS GUIDELINES
The SP-125 Plus can be used for welding mild steel
using the GMAW, single pass, process which requires
a supply of shielding gas or it can be used for the self
shielded, Innershield electrode process.
CAUTION
It is important when changing between welding
with steel wire and aluminum to exchange feeding
components due to the lubricant applied to steel
wire. Failure to do so may result in contaminated
welds when welding aluminum.
The recommended gas and electrode for GMAW is
welding grade mixed CO
and 0.025” (0 6 mm) diameter Lincoln L-56 mild-steel
welding wire [supplied on 121/2 Ib (6 kg) spools]. For
14 gauge (2,0 mm) and thinner CO
acceptable. A mixed gas consisting of 75 to 80%
Argon and 20 to 25% CO2is recommended for welding on heavier gauge [12 gauge (2,5 mm) for example]
steel.
The recommended electrode for the self-shielded
process is 0.035” (0,9 mm) diameter Lincoln
Innershield NR-211-MP on 10 Ib (4,5 kg) spools. This
electrode can be used for all position welding of 20
gauge through 5/16” (1,0 – 8,0 mm) thick steel [multiple passes are required for 1/4” and 5/16” (6,0 and 8,0
mm)].
and Argon (75-80%) gas
2
, or blended gas is
2
WARNING
Use of the GMAW process with the SP-125 Plus on
thicker materials than recommended may result in
poor welds. The welds may “look” good, but may
just be “sitting” on top of the plate. This is called
“cold casting” and will result in weld failure.
The SP-125 Plus is shipped from the factory ready to
feed 0.023-0.025” (0,6 mm) diameter wire. To operate
the SP-125 Plus with other sizes of wire, it is necessary to change the contact tip and change the drive
roll over to other sizes. Refer to Changing the Contact
Tip and Changing the Drive Roll, in the MAINTENANCE section, for specific information on these procedures.
WELDING WITH FCAW (Innershield)
Welding with Innershield requires an Innershield
Welding Kit. A gasless nozzle is provided in the
Innershield Welding Kit. When using Innershield electrode, installing the gasless nozzle will improve visibility of the arc and protect the gas diffuser from weld
spatter. Additionally included is a gun cable liner to
permit proper feeding of .035” (0,9 mm) Innershield
wire. Refer to the ACCESSORIES section for details
on obtaining this kit.
The SP-125 Plus is suitable for .035" Aluminum wire
and .030" stainless wire. Refer to Table B.1 for
Recommended Procedure Settings. Aluminum wire
requires K663-1 Aluminum Welding kit. See ACCESSORIES section.
SP-125 PLUS
OPERATION
OVERLOAD PROTECTION
Output Overload
The SP-125 Plus is equipped with a circuit breaker
which protects the machine from potential damage
from excessive output current. The circuit breaker button will extend out when tripped. The circuit breaker
must be manually reset.
Thermal Protection
The SP-125 Plus duty cycle is exceeded a thermostat
will shut off the output until the machine cools to a normal operating temperature. This is an automatic function and is self resetting.
Wire Feed Overload Protection
If the SP-125 Plus has an automatic electronic protection circuit to protect the wire feed motor. If excessive
motor overload occurs (due to excessive feeding
force, jammed drive rolls, or shorted motor leads) the
circuit will shut down the wire feed motor and the
welding power output.
B-7
The wire feed shut-down circuit will reset automatically
when the gun trigger is released. However shut-down
will reoccur if the overload situation is not corrected.
SP-125 PLUS
B-8
LEARNING TO WELD
LEARNING TO WELD
No one can learn to weld simply by reading about it.
Skill comes only with practice. The following pages will
help the inexperienced operator to understand welding and develop this skill. For more detailed information, order a copy of “New Lessons in Arc Welding”
listed at the end of this manual.
THE ARC-WELDING CIRCUIT
The operator’s knowledge of arc welding must go
beyond the arc itself. The operator must know how to
control the arc, and this requires a knowledge of the
welding circuit and the equipment that provides the
electric current used in the arc. Figure B.7 illustrates
the welding circuit for a typical welding machine. The
circuit begins where the gun cable is attached to the
welding machine. Current flows through the gun cable,
gun, and contact tip, to the wire and across the arc.
On the work side of the arc, current flows through the
base metal to the work cable and back to the welding
machine. This circuit must be complete for the current
to flow.
This machine’s welding circuit has a voltage output of
33 volts DC maximum. This voltage is quite low and is
only present when the gun trigger is depressed.
To weld, the work clamp must be tightly connected to
clean base metal. Remove paint, rust, dirt or oil as
necessary and connect the work clamp as close as
possible to the area you wish to weld. This helps prevent current from going through an unwanted path.
Avoid allowing the welding circuit to pass through
hinges, bearings, electronic components, or similar
devices that can be damaged. See Figure B.8. Always
disconnect electrical devices before welding upon
them.
WARNING
Fumes and slag generated from
Innershield type electrodes recommended for use with this welding
machine can be toxic.
• Avoid contact with eyes and skin.
• Do not take internally.
• Keep out of reach of children.
• Follow all safety precautions
found in this operating manual.
The gun and cable assembly is held by the operator
who guides the automatically fed wire along the joint,
maintaining a contact tip to work distance of about 3/8
to 1/2 inch (10 – 12 mm). This is called electrical stickout. This electrical stickout (ESO) must be properly
maintained by the operator. The electric arc is made in
the gap between the work and the tip end of a small
diameter wire. When the power source is properly set,
the arc gap is maintained automatically.
Arc welding is a manual skill requiring a steady hand,
good physical condition, and good eyesight. The operator controls the welding arc, and therefore, the quality
of the weld made.
THE SELF-SHIELDED FCAW WELDING
ARC
Figure B.9 illustrates the action taking place in the self
shielded FCAW (Innershield) welding arc. It closely
resembles what is actually seen while welding.
SP-125 PLUS
FIGURE B.8
Electronic Components
HingesBearings
Protective Slag
Weld Metal
Cored Wire
FIGURE B.9
Burning of core materials
inside wire electrode
results in shield of gas.
Arc Stream
LEARNING TO WELD
B-9
The “arc stream” is seen in the middle of the picture.
This is the electric arc created by the electric current
flowing through the space between the end of the wire
electrode and the base metal. The temperature of this
arc is about 6000°F, which is more than enough to
melt metal. The arc is very bright, as well as hot, and
cannot be looked at with the naked eye without risking
painful injury. The very dark lens, specifically
designed for arc welding must be used with the hand
or face shield whenever viewing the arc.
The arc melts the base metal and actually digs into it
much as water through a nozzle on a garden hose
digs into the earth. The molten metal forms a molten
pool or crater and tends to flow away from the arc. As
it moves away from the arc, it cools and solidifies.
The function of the Innershield cored wire electrode is
much more than simply to carry current to the arc. The
wire core is composed of fluxes and/or alloying ingredients around which a steel sheath has been formed.
It is simply a stick electrode turned inside out in a continuous wire form.
The cored wire melts in the arc and tiny droplets of
molten metal shoot across the arc into the molten
pool. The wire sheath provides additional filler metal
for the joint to fill the groove or gap between the two
pieces of base metal.
The core materials also melt or burn in the arc and
perform several functions. They make the arc steadier, provide a shield of smoke-like gas around the arc
to keep oxygen and nitrogen in the air away from the
molten metal, and provide a flux for the molten pool.
The flux picks up impurities and forms the protective
slag on top of the weld during cooling.
After running a weld bead, the slag may be removed
with a chipping hammer and wire brush. This
improves appearance and allows for inspection of the
finished weld.
THE GMAW (MIG) WELDING ARC
Figure B.10 illustrates the GMAW (MIG) welding arc.
Solid wire does not contain fluxes or ingredients to
form its own shielding and no slag forms to protect the
molten weld metal. For this reason, a continuous even
flow of shielding gas is needed to protect the molten
weld metal from atmospheric contaminants such as
oxygen and nitrogen. Shielding gas is supplied
through the gun and cable assembly, through the gas
nozzle and into the welding zone.
Gas nozzle
Solid wire
electrode
Base metal
FIGURE B.10
When comparing the GMAW and FCAW processes,
you can see that the principal difference between the
two lies in the type of shielding used. GMAW uses gas
for shielding, thus we have Gas Metal Arc Welding.
FCAW uses the melting or burning of the core ingredients for shielding, and is thus termed Self-Shielded
Flux Cored Arc Welding.
The recommended wire for Gas Metal Arc Welding
(MIG) is Lincolnweld 0.025” (0.6 mm) L-56 electrode.
Lincolnweld” L-56 is capable of welding a wide range
of mild steels in all positions, however, more skill is
required for out-of-position welding with the GMAW
process.
Shielding gas
Weld metal
Since machine size and output characteristics limit the
size and type of wire electrode which can be used,
Lincoln 0.035" (0.9mm) NR-211-MP Innershield electrode is recommended for Self-Shielded Flux Cored
Arc Welding with this machine.
PROCESS SELECTION
By gaining knowledge of the differences between the
two processes, you will be able to select the best
process for the job you have at hand. In selecting a
process, you should consider:
For GMAW (MIG) Process
1. Is most of my welding performed on 16 gauge and
lighter materials?
SP-125 PLUS
B-10
LEARNING TO WELD
2. Can I afford the extra expense, space, and lack of
portability required for gas cylinders and gas supply?
3. Do I require clean, finished-looking welds?
If you have answered yes to all the above questions
GMAW may be the process for you. If you have
answered no to any of the above questions, then you
should consider using the FCAW process.
For FCAW (Innershield) Process
1. Do I want simplicity and portability?
2. Will welding be performed outdoors or under windy
conditions?
3. Do I require good all position welding capability?
4. Will most welding be performed on 16 gauge and
heavier, somewhat rusty or dirty materials?
5. Weld must be cleaned prior to painting.
COMMON METALS
Most metals found around the farm, small shop or
home are low carbon steel, sometimes referred to as
mild steel. Typical items made with this type of steel
include most sheet metal, plate, pipe and rolled
shapes such as channels and angle irons. This type of
steel can usually be easily welded without special precautions. Some steels, however, contain higher carbon levels or other alloys and are more difficult to
weld. Basically, if a magnet sticks to the metal and
you can easily cut the metal with a file, chances are
good that the metal is mild steel and that you will be
able to weld the material. In addition, aluminum and
stainless steel can be welded using the K664-1
Aluminum Welding Kit. For further information on
identifying various types of steels and other metals,
and for proper procedures for welding them, we again
suggest you purchase a copy of “New Lessons in Arc
Welding”.
JOINT TYPES AND POSITIONS
Five types of welding joints are: Butt Welds, Fillet
Welds, Lap Welds, Edge Welds and Corner Welds.
See Figure B.11.
Of these, the Butt Weld and Fillet Weld are the two
most common welds.
Butt weldLap weld
Edge weldFillet weldCorner weld
FIGURE B.11
Butt Welds
Place two plates side by side, leaving a space approximately one half the thickness of the metal between
them in order to get deeper penetration.
Securely clamp or tack weld the plates at both ends,
otherwise the heat will cause the plates to move apart.
See Figure B.12.
Now weld the two plates together. Weld from left to
right (if right handed). Point the wire electrode down in
the crack between the two plates, keeping the gun
slightly tilted in the direction of travel. Watch the
molten metal to be sure it distributes itself evenly on
both edges and in between the plates. This is refered
to as the “pull technique”. On thin gauge sheet metal,
use the “push technique”. See “Welding Techniques
for GMAW (MIG) Process”.
Regardless of the type of metal being welded, in order
to get a quality weld, it is important that the metal is
free of oil, paint, rust or other contaminants.
SP-125 PLUS
LEARNING TO WELD
B-11
45°
FIGURE B.12
Penetration
Unless a weld penetrates close to 100% of the metal
thickness, a butt weld will be weaker than the material
welded together. In the example shown in Figure
B.13, the total weld is only half the thickness of the
material thus the weld is only approximately half as
strong as the metal.
FIGURE B.13
FIGURE B.15
Welding In The Vertical Position
Welding in the vertical position can be done either vertical-up or vertical-down. Vertical-up is used whenever
a larger, stronger weld is desired. Vertical-down is
used primarily on sheet metal 5/32” (3.9 mm) and
under for fast, low penetrating welds.
WARNING
Use of this unit on thicker materials than recommended may result in poor welds. The welds may
“look” good, but may just be “sitting” on top, of
the plate. This is called “Cold Casting” and will
result in weld failure.
Vertical-up And Overhead Welding
The problem, when welding vertical-up, is to put the
molten metal where it is wanted and make it stay
there. If too much molten metal is deposited, gravity
will pull it downwards and make it “drip”. Therefore, a
certain technique has to be followed.
FIGURE B.14
In the example shown in Figure B.14, the joint has
been welded so that 100% penetration could be
achieved. The weld, if properly made, is as strong as
or stronger than the original metal.
Fillet Welds
When welding fillet welds, it is very important to hold
the wire electrode at a 45° angle between the two
sides or the metal will not distribute itself evenly. The
gun nozzle is generally formed at an angle to facilitate
this. See Figure B.15.
When welding out-of-position, run stringer beads.
Don’t whip, break the arc, move out of the puddle, or
move too fast in any direction. Use Wire Feed Speed
(WFS) in the low portion of the range. The general
technique and proper gun angle is illustrated in Figure
B.16.
Generally, keep the electrode nearly perpendicular to
the joint as illustrated. The maximum angle above perpendicular may be required if porosity becomes a
problem.
SP-125 PLUS
B-12
PROPER GUN ANGLE
FOR GMAW PROCESS
WELDING IN THE VERTICAL UP POSITION
PROPER GUN ANGLE
FOR FCAW PROCESS
WELDING IN THE VERTICAL UP POSITION
LEARNING TO WELD
FIGURE B.16
Vertical-down Welding
Refer to Figure B.17 Vertical-down welds are applied
at a fast pace. These welds are therefore shallow and
narrow and, as such, are excellent for sheet metal.
Vertical-down welds may be applied to 5/32” (3.9 mm)
and lighter material.
Use stringer beads and tip the gun in the direction of
travel so the arc force helps hold the molten metal in
the joint. Move as fast as possible consistent with
desired bead shape.
MACHINE SET UP FOR THE
SELF-SHIELDED FCAW PROCESS
1. See PROCESS GUIDELINES in the OPERATION
section for selection of welding wire and shielding
gas, and for range of metal thicknesses that can be
welded.
2. See the Application Guide on the inside of wire
feed section door for information on setting the
controls.
3. Set the “Voltage” and “Wire Speed” controls to the
settings suggested on the Application Guide for the
welding wire and base metal thickness being used.
The voltage control is marked “V” and the wire feed
speed is marked ‘’olo.’’
4. Check that the polarity is correct for the welding
wire being used. Set the polarity for DC(–) when
welding with NR-211-MP Innershield electrode.
See Work Cable Installation in the INSTALLATION
section for instructions on changing polarity.
5. When using Innershield electrode, the gasless nozzle may be used instead of a gas nozzle to improve
visibility of the arc.
The important thing is to continue lowering the entire
arm as the weld is made so the angle of the gun does
not change. Move the electrode wire fast enough that
the slag does not catch up with the arc. Vertical-down
welding gives thin, shallow welds. It should not be
used on heavy material where large welds are
required.
FIGURE B.17
6. Connect work clamp to metal to be welded. Work
clamp must make good electrical contact to the
work piece. The work piece must also be grounded
as stated in the “Arc Welding Safety Precautions”
at the beginning of this manual.
WELDING TECHNIQUES FOR THE SELFSHIELDED FCAW PROCESS
Four simple manipulations are of prime importance
when welding. With complete mastery of the four,
welding will be easy. They are as follows:
1. The Correct Welding Position
Figure B.18 illustrates the correct welding position
for right handed people. (For left handed people, it
is the opposite.)
Hold the gun (of the gun and cable assembly) in
your right hand and hold the shield with your left
hand. (Left handers simply do the opposite.)
When using the FCAW Process, weld from left to
right (if you are right handed). This enables you to
clearly see what you are doing. (Left handers do
the opposite.) Tilt the gun toward the direction of
travel holding the electrode at an angle as shown
in Figure B.18.
SP-125 PLUS
FIGURE B.18
WARNING
LEARNING TO WELD
Contact Tip
Wire Electrode
B-13
3/8 – 1/2” (10 – 12 mm)
Electrical Stickout (ESO)
ARC RAYS can burn eyes and skin.
When using an open arc process, it
Is necessary to use correct eye,
head and body protection.
Protect yourself and others, read
“ARC RAYS can burn” at the front
of this manual.
2. The Correct Way To Strike An Arc
1. Be sure the work clamp makes good electrical
contact to the work.
2. Position gun over joint. End of wire may be
lightly touching the work.
3. Position face shield to protect face and eyes,
close gun trigger, and begin welding. Hold the
gun so that the contact tip to work distance is
about 3/8 to 1/2 inch (10 – 12 mm).
4. To stop welding, release the gun trigger and
the pull the gun away from the work after the
arc goes out.
FIGURE B.19
The easiest way to tell whether the ESO is the correct length is by listening to its sound. The correct
ESO has a distinctive “crackling” sound, very much
like eggs frying in a pan. A long ESO has a hollow,
blowing or hissing sound. If the ESO is too short,
you may stick the contact tip or nozzle to the weld
puddle and/or fuse the wire to the contact tip.
4. The Correct Welding Speed
The important thing to watch while welding is the
puddle of molten metal right behind the arc. See
Figure B.20. Do not watch the arc itself. It is the
appearance of the puddle and the ridge where the
molten puddle solidifies that indicates correct welding speed. The ridge should be approximately 3/8”
(10 mm) behind the wire electrode.
Most beginners tend to weld too fast, resulting in a
thin uneven, “wormy” looking bead. They are not
watching the molten metal.
5. A ball may form at the tip end of the wire after
welding. For easier restrikes (with Innershield
wire) the ball may be removed by feeding out a
few inches of wire and simply bending the wire
back and forth until it breaks off.
6. When no more welding is to be done, turn off
the machine.
3. The Correct Electrical Stickout (ESO)
The electrical stickout (ESO) is the distance from
the end of the contact tip to the end of the wire.
See Figure B.19.
Once the arc has been established, maintaining
the correct ESO becomes extremely important.
The ESO should be approximately 3/8 to 1/2 inch
(10 to 12 mm) long.
Solidifying ridge
Molten puddle
FIGURE B.20
SP-125 PLUS
B-14
LEARNING TO WELD
Helpful Hints
1. For general welding, it is not necessary to weave
the arc, neither forward or backward nor sideways.
Weld along at a steady pace. You will find it easier.
2. When welding on thin plate, you will find that you
will have to increase the welding speed, whereas
when welding on heavy plate, it is necessary to go
more slowly in order to get good penetration.
3. When welding sheet metal 16 gauge (1.5 mm) and
lighter, heat buildup may cause part warpage and
burn through. One way to eliminate these problems
is to use the back-stepping method illustrated in
Figure B.21.
First weld from A to B; then from C to A; then
from D to C; then from E to D, and so on.
BACDE
Back-Stepping
FIGURE B.21
Practice
The best way of getting practice in the four skills that
enable you to maintain:
1. Correct welding position
2. Correct way to strike an arc
3. Correct electrical stickout
4. Correct welding speed
For the SP-125 Plus, use the following:
Mild Steel16 gauge or 1/16 inch
(1.6 mm)
Electrode0.035" (0.9 mm)
NR-211-MP
Innershield Wire
Voltage Setting “V”E
Wire Feed Speed “o|o”2
Refer to Figure B.22.
1. Learn to strike an arc by positioning the gun over
the joint and touching the wire to the work.
2. Position face shield to protect face and eyes.
3. Depress gun trigger, hold gun so contact tip to
work distance is about 3/8 to 1/2 inch (10 to 12
mm) and the gun is at proper angle.
4. After you strike the arc, practice the correct electrical stickout. Learn to distinguish it by its sound.
5. When you are sure that you can hold the correct
electrical stickout, with a smooth “crackling” arc
start moving. Look at the molten puddle constantly,
and look at the “ridge” where the metal solidifies.
6. Run beads on a flat plate. Run them parallel to the
top edge (the edge farthest away from you). This
gives you practice in running straight welds, and
also gives you an easy way to check your
progress. The 10th weld will look considerably better than the first weld. By constantly checking on
your mistakes and your progress, welding will soon
be a matter of routine.
is to perform the following exercise.
Contact
Tip
ESO
Gun Angle
FIGURE B.22
SP-125 PLUS
LEARNING TO WELD
MACHINE SET UP FOR THE GMAW (MIG)
PROCESS
1. See PROCESS GUIDELINES in the OPERATION
section for selection of welding wire and shielding
gas, and for range of metal thicknesses that can be
welded.
B-15
2. See the Application Guide on the inside of wire
feed section door for information on setting the
controls.
3. Set the “Voltage” and “Wire Speed” controls to the
settings suggested on the Application Guide for the
welding wire and base metal thickness being used.
The voltage control is marked “V” and the wire feed
speed is marked ‘’olo.’’
4. Check that the polarity is correct for the welding
wire being used. Set the polarity for DC(+) when
welding with the GMAW (MIG) process. See Work
Cable Installation in the INSTALLATION section for
instructions for changing polarity.
5. Check that the gas nozzle and proper size liner
and contact tip are being used and that the gas
supply is turned on. If adjustable, set for 15 to 20
cubic feet per hour (7 to 10 l/min.) under normal
conditions, increase to as high as 35 CFH (17
I/min.) under drafty (slightly windy) conditions.
6. Connect work clamp to metal to be welded. Work
clamp must make good electrical contact to the
work piece. The work piece must also be grounded
as stated in the “Arc Welding Safety Precautions”
at the beginning of this manual.
FIGURE B.23
When using the GMAW process on light gauge material, weld from right to left (if you are right handed).
This results in a colder weld and has less tendency for
burn through.
2. The Correct Way To Strike An Arc
WARNING
ARC RAYS can burn eyes and skin.
When using an open arc process, it
Is necessary to use correct eye,
head and body protection.
Protect yourself and others, read
“ARC RAYS can burn” at the front
of this manual.
1. Be sure the work clamp makes good electrical contact to the work.
2. Position gun over joint. End of wire may be lightly
touching the work.
WELDING TECHNIQUES FOR THE GMAW
(MIG) PROCESS
Four simple manipulations are of prime importance
when welding. With complete mastery of the four,
welding will be easy. They are as follows:
1. The Correct Welding Position
Figure B.23 illustrates the correct welding position
for right handed people. (For left handed people, it
is the opposite.)
When GMAW (MIG) welding on sheet metal, it is
important to use the “forehand” push technique.
Hold the gun (of the gun and cable assembly) in
your right hand and hold the shield with your left
hand. (Left handers simply do the opposite.)
3. Position face shield to protect face and eyes, close
gun trigger, and begin welding. Hold the gun so
that the contact tip to work distance is about 3/8 to
1/2 inch (10 – 12 mm).
4. To stop welding, release the gun trigger and pull
the gun away from the work after the arc goes out.
5. A ball may form at the tip end of the wire after
welding. For easier restrikes, the ball may be
removed by feeding out a few inches of wire and
cutting off the end of the wire with wire cutters.
6. When no more welding is to be done, close the
valve on the gas cylinder, momentarily operate the
gun trigger to release gas pressure, then turn off
the machine.
SP-125 PLUS
B-16
Contact Tip
Wire Electrode
LEARNING TO WELD
ESO
FIGURE B.24
3. The Correct Electrical Stickout (ESO)
The electrical stickout (ESO) is the distance from
the end of the contact tip to the end of the wire.
See Figure B.24.
Once the arc has been established, maintaining
the correct ESO becomes extremely important.
The ESO should be approximately 3/8 to 1/2 inch
(10 to 12 mm) long.
The easiest way to tell whether the ESO is the correct length is by listening to its sound. The correct
ESO has a distinctive “crackling” sound, very much
like eggs frying in a pan. A long ESO has a hollow,
blowing or hissing sound. If the ESO is too short,
you may stick the contact tip or nozzle to the weld
puddle and/or fuse the wire to the contact tip.
4. The Correct Welding Speed
The important thing to watch while welding is the
puddle of molten metal right behind the arc. See
Figure B.25. Do not watch the arc itself. It is the
appearance of the puddle and the ridge where the
molten Puddle solidifies that indicates correct welding speed. The ridge should be approximately 3/8”
(10 mm) behind the wire electrode.
Most beginners tend to weld too fast, resulting in a
thin, uneven, “wormy” looking bead. They are not
watching the molten metal.
Helpful Hints
1. For general welding, it is not necessary to weave
the arc, neither forward or backward nor sideways.
Weld along at a steady pace. You will find it easier.
2. When welding on thin plate, you will find that you
will have to increase the welding speed, whereas
when welding on heavy plate, it is necessary to go
more slowly in order to get good penetration.
3. When welding sheet metal 16 gauge (1.5 mm) and
lighter, heat buildup may cause part warpage and
burn through. One way to eliminate these problems
is to use the back-stepping method illustrated in
Figure B.21.
Practice
The best way of getting practice in the four skills that
enable you to maintain:
1. Correct welding position
2. Correct way to strike an arc
3. Correct electrical stickout
4. Correct welding speed
is to perform the following exercise.
For the SP-125 Plus, use the following:
Mild Steel16 gauge or 1/16 inch
(1.6 mm)
ElectrodeLincolnweld 0.025 L-56
electrode
CO
2
Voltage Setting “V”G
Wire Feed Speed “o|o”5
Refer to Figure B.22.
Weld metal ridge
SP-125 PLUS
FIGURE B.25
Molten puddle
Base metal
1. Learn to strike an arc by positioning the gun over
the joint and touching the wire to the work.
2. Position face shield to protect face and eyes.
3. Depress gun trigger, hold gun so contact tip to
work distance Is about 3/8 to 1/2 inch (10 to 12
mm) and the gun is at proper angle.
LEARNING TO WELD
B-17
4. After you strike the arc, practice the correct electrical stickout. Learn to distinguish it by its sound.
5. When you are sure that you can hold the correct
electrical stickout, with a smooth “crackling” arc,
start moving. Look at the molten puddle constantly.
6. Run beads on a flat plate. Run them parallel to the
top edge (the edge farthest away from you). This
gives you practice in running straight welds, and
also gives you an easy way to check your
progress. The 10th weld will look considerably better than the first weld. By constantly checking on
your mistakes and your progress, welding will soon
be a matter of routine.
TROUBLESHOOTING WELDS
Good welds have excellent appearance.
2. Decrease stickout.
3. Decrease WFS (wire feed speed.
4. Decrease travel speed.
5. Decrease drag angle.
6. Check for correct gas, if used.
To Reduce Spatter (in order of importance):
1. Increase voltage.
2. Increase drag angle.
3. Decrease stickout.
4. Increase WFS (wire feed speed).
5. Decrease travel speed.
6. Check for correct gas, if used.
To Eliminate Porosity (in order of importance):
1. Turn on gas supply, if used
2. Decrease voltage.
3. Increase stickout.
4. Increase WFS (wire feed speed).
5. Decrease drag angle.
6. Decrease travel speed.
NOTE: Always be sure the joint is free from moisture,
oil, rust, paint or other contaminants.
To Eliminate a Ropy Convex Bead
(in order of importance):
1. Increase voltage
To Correct Poor Penetration (in order of importance):
1. Decrease stickout.
2. Increase WFS (wire feed speed).
3. Increase voltage.
4. Decrease speed.
5. Decrease drag angle.
6. Check for correct gas, if used.
If Arc Blow Occurs (in order of importance):
NOTE: Try different ground connection locations
before adjusting procedures.
1. Decrease drag angle.
2. Increase stickout.
3. Decrease voltage.
4. Decrease WFS (wire feed speed.
5. Decrease travel speed.
To Eliminate Stubbing* (in order of importance):
1. Increase voltage
2. Decrease WFS (wire feed speed)
3. Decrease stickout
4. Increase drag angle
* Stubbing occurs when the electrode drives through
the molten puddle and hits the bottom plate tending
to push the gun up.
SP-125 PLUS
B-18
Proper Gun Handling
Most feeding problems are caused by improper handling of the gun cable or electrodes.
1. Do not kink or pull the gun around sharp corners
2. Keep the gun cable as straight as practical when
welding.
3. Do not allow dolly wheels or trucks to run over the
cables.
4. Keep the cable clean.
5. Innershield electrode has proper surface lubrication. Use only clean, rust-free electrode.
6. Replace contact tip when it becomes worn or the
end is fused or deformed.
LEARNING TO WELD
SP-125 PLUS
APPLICATION CHART
B-19
SP-125 PLUS
C-1
ACCESSORIES
OPTIONAL ACCESSORIES
1. K520 Utility Cart — Designed to transport the
Lincoln family of small welders. Has provisions for
mounting a single gas cylinder. Has front casters
and large rear wheels. Handle height is easily
adjustable. Bottom tray provided for tools and
accessories. Easy assembly required; takes less
than 15 minutes.
2. K1800-1 CO
Includes an adjustable pressure flow regulator for
use on CO
Weld shielding gas may be obtained from a welding supply distributor.
Also included is a gas hose which connects to the
rear of the welder.
See “Gas Connection” in Installation section for
installation instructions.
3. K1799-1 Argon-Mixed Gas Adjustable
Regulator and Hose Kit
Includes an adjustable pressure and flow regulator
for use on argon-mixed gas cylinders. Also included is a gas hose which connects to the rear of the
welder.
Adjustable Regulator and Hose Kit —
2
cylinders.
2
(1)
6. KP666-035C Knurled Drive Roll (optional) —
Reversible Drive Roll with double knurled grooves
for .035 (0.9 mm) cored electrode.
7. K695-2 Spot / Stitch Timer Kit — Includes spot
timer to control the spot welding arc time, and a
stitch timer to control the on/off cycle time of the
arc to prevent burnthrough on thin gauge metals.
Also includes spot welding nozzle.
The Spot/Stitch Timer Kit installs inside the wire
feed compartment, replacing the blank panel located below the gun trigger lead connectors, per the
installation instructions included with the kit.
8. K697-1 Power Cord Extension — Extension 115V
power cord (20’/6.1m) allows extra convenience
when work is located some distance away from
power receptacle.
9. K549-1 .035 (0.9 mm) Innershield Welding Kit
Includes a contact tip, a gasless nozzle and a cable
liner to permit the Magnum™ 100L gun and cable
to use .035” (0.9 mm) diameter flux-cored electrode. Also included is a spool of .035 (0.9 mm)
Innershield NR-211-MP.
4. K586-1 Deluxe Adjustable Gas Regulator &
Hose Kit
Accommodates CO
or mixed Gas Cylinders.
2
5. K663-2 Aluminum Welding Kit — This kit
required for welding with .035 Aluminum wire.
Included with this kit are a drive roll, liner and contact tip. It is important when changing between
welding with steel wire and aluminum to
exchange these components due to the lubricant applied to steel wire. Failure to do so may
result in contaminated welds when welding aluminum.
See Maintenance section for instructions on
installing drive roll, cable liner, contact tip and their
proper configuration.
(1)
This regulator comes standard with a 4.5 foot hose
with the SP125+.
SP-125 PLUS
ACCESSORIES
C-2
INNERSHIELD (FCAW)
CONVERSION
Several changes are needed to convert the unit for
operation with the Innershield (FCAW) process. The
K549-1 Innershield Kit includes all the necessary
accessories for this conversion and are provided for
this purpose. The following conversions should be
made using the contents of this kit:
1. Change the output polarity to DC(-). See “Work
Cable Installation” section for details.
2. Install proper drive roll for the wire size selected.
See “Changing Drive Roll” in Maintenance section
for details.
3. Install the proper gun liner and tip for the wire size
selected. See “Component Replacement” in
Maintenance section for details.
4. Remove gas nozzle (if installed) and install gasless
nozzle. To remove, simply unscrew.
REPLACEMENT PARTS
Complete Gun and Cable Assembly
L8311-6 (K530-4)
Contact Tip .025” (0.6 mm)
S19726-1
Contact Tip .030” (0.8 mm)
S19726-2
Contact Tip .035” (0.9 mm)
S19726-3
Contact Tip .045” (1.2 mm)
S19726-4
Contact Tip-Tapered .025” (0.6 mm)
S20278-1
Contact Tip-Tapered .030” (0.8 mm)
S20278-2
Contact Tip-Tapered .035” (0.9 mm)
S20278-3
Contact Tip-Tapered .045” (1.2mm)
S20278-4
Liner .023 - .030” (0.6 - 0.8 mm)
M16291-2
Liner .030 - .035” (0.8 - 0.9 mm)
M16291-6
Liner .035/.045” (0.9/1.2 mm)
M16291-1
Gas Diffuser
S19728
Gas Nozzle
M16294
Gas Nozzle-Tip Recessed 3/8” (9.5 mm)
Opening I.D.
M16684
Gas Nozzle-Tip Recessed 1/2” (12.7 mm)
Opening I.D.
M16684-1
Gas Nozzle-Tip Recessed 5/8” (15.9 mm)
Opening I.D.
M16684-2
Spot Welding Nozzle
M17846-1
Gasless Nozzle (Innershield Only)
M16418
SP-125 PLUS
D-1
MAINTENANCE
MAINTENANCE
SAFETY PRECAUTIONS
WARNING
ELECTRIC SHOCK can kill.
• Disconnect input power by removing plug from receptacle before
working inside SP-125 PLUS. Use
only grounded receptacle. Do not
touch electrically “hot” parts
inside SP-125 PLUS.
• Have qualified personnel do the
maintenance and trouble shooting
work.
ITEMS REQUIRING NO
MAINTENANCE
• Drive Motor and Gearbox – Lifetime lubrication
• Fan Motor- Lifetime lubrication.
• Wire Reel Spindle – Do NOT lubricate shaft.
AFTER FEEDING 50# OF FLUX CORED
WIRE OR 300# OF SOLID WIRE
• Unplug machine or turn power switch to OFF – “O”
position. Remove gun and cable from machine.
• Remove gas nozzle and contact tip from gun.
• Lay cable out straight - blow out gently into gun end
with compressed air. Bend cable back and forth –
blow out again – Repeat until clean.
WARNING
Excessive pressure at start may cause the dirt to
form a plug.
PERIODICALLY AS REQUIRED
• Blow dirt out of the welder with low pressure air to
eliminate excessive dirt and dust buildup that could
cause welder to run hot.
• Blow dirt out of: Rectifier & Fan Motor Assembly;
PC Board located on Case Side Assembly; and
Center Assembly components.
ROUTINE AND PERIODIC MAINTENANCE
BEFORE EACH USE
• Check over machine and accessories for any obvious
condition that may prevent safe performance or operation, repair or replace items as necessary to correct
any abnormal condition.
AFTER 5 MINUTES OF WELDING
or when spatter accumulates in nozzle
• Clean nozzle to avoid bridging between nozzle and
contact tip which results in shorted nozzle, poor welds
and overheated gun. Hint: Anti-stick spray or gel
available from a welding supply distributor may
reduce buildup and aid in spatter removal.
AFTER EACH SPOOL OF WIRE FEED
• Remove contact tip and clean inside diameter with
short piece of wire
• Clean cable liner – when rough and erratic wire feeding occur.
• Vacuum accumulated dirt from gearbox and wire
feed section.
• Inspect the incoming guide tube and clean inside
diameter if necessary. Replace when excessively
worn.
• Replace Contact Tip – when hole is enlarged or
elongated (refer to “CHANGING THE CONTACT
TIP”, in this section).
• Replace gas nozzle.
• Replace Liner – when wire feeding problems occur
and other items have been checked (refer to
“CHANGING LINER” procedure in this section).
• Replace internal gun handle parts as necessary
(see Procedure at the end of this section).
SP-125 PLUS
MAINTENANCE
D-2
GUN AND CABLE
MAINTENANCE
FOR MAGNUM™ 100L GUN
Gun Cable Cleaning
Clean cable liner after using approximately 300 lbs
(136 kg) of solid wire or 50 lbs (23 kg) of flux-cored
wire. Remove the cable from the wire feeder and lay it
out straight on the floor. Remove the contact tip from
the gun. Using low pressure air, gently blow out the
cable liner from the gas diffuser end.
CAUTION
Excessive pressure at the start may cause the dirt
to form a plug.
Flex the cable over its entire length and again blow
out the cable. Repeat this procedure until no further
dirt comes out.
Contact Tips, Nozzles, and Gun Tubes
1. Dirt can accumulate in the contact tip hole and
restrict wire feeding. After each spool of wire is
used, remove the contact tip and clean it by pushing a short piece of wire through the tip repeatedly.
Use the wire as a reamer to remove dirt that may
be adhering to the wall of the hole through the tip.
2. Replace worn contact tips as required. A variable
or “hunting” arc is a typical symptom of a worn contact tip. To install a new tip, choose the correct size
contact tip for the electrode being used (wire size is
stenciled on the side of the contact tip) and screw it
snugly into the gas diffuser.
3. Remove spatter from inside of gas nozzle and from
tip after each 10 minutes of arc time or as required.
4. Be sure the gas nozzle is fully screwed onto the
diffuser for gas shielded processes. For the
Innershield®process, the gasless nozzle should
be screwed onto the diffuser.
5. To remove gun tube from gun, remove gas nozzle
or gasless nozzle and remove diffuser from gun
tube. Remove both collars from each end of the
gun handle and separate the handle halves.
Loosen the locking nut holding the gun tube in
place against the gun end cable connector.
Unscrew gun tube from cable connector. To install
gun tube, screw the locking nut on the gun tube as
far as possible. Then screw the gun tube into the
cable connector until it bottoms. Then unscrew (no
more than one turn) the gun tube until its axis is
perpendicular to the flat sides of the cable connector and pointed in the direction of the trigger.
Tighten the locking nut so as to maintain the proper
relationship between the gun tube and the cable
connector. Replace the gun handle, trigger and diffuser. Replace the gas nozzle or gasless nozzle.
CONFIGURATION OF COMPONENTS IN WIRE FEEDING SYSTEM
• If .030 Solid wire feeding is desired obtain an S19726-2 Contact Tip, an M16291-2 Cable Liner and an M15448 Drive Roll (Smaller Groove).
* It is important when changing between welding with steel wire and aluminum to exchange feeding components due to the lubricant applied to steel wire. Failure
to do so may result in contaminated welds when welding aluminum.
Δ Recommended for best feeding performance.
SP-125 PLUS
D-3
MAINTENANCE
COMPONENT REPLACEMENT
PROCEDURES
CHANGING THE CONTACT TIP
1. Unplug or turn power switch to Off “O” position.
2. Refer to Figure D.2. Remove the gas nozzle from
the gun by unscrewing counter-clockwise.
3. Remove the existing contact tip from the gun by
unscrewing counter-clockwise.
4. Insert and hand tighten desired contact tip.
5. Replace gas nozzle.
CHANGING THE SP-125 Plus FOR USE
WITH INNERSHIELD FLUX CORED WIRE
• Change The Contact Tip
1. Refer to Figure D.2. Remove the gas nozzle from
the gun by unscrewing counter-clockwise.
2. Remove the existing contact tip from the gun by
unscrewing counter-clockwise.
CAUTION
When inching the welding wire, the drive rolls,
gun connector block, and gun contact tip are
energized relative to work and ground and remain
energized for several seconds after the gun trigger is released.
4. Remove the drive roll, flip over and reinstall with the
opposite groove closest to the gearbox.
NOTE: The stencil of the groove that you want to use
is marked on the outside of the drive unit
(when installed)
5. Push a length of straightened welding wire through
the wire feeder guide tubes and reset the Phillips
Head screw to secure the drive roll onto the shaft.
6. Reapply the spring loaded idle arm tensioner.
7. Turn the power “ON” (I) and check the drive roll for
slipping when feeding wire.
necessary, tighten or loosen the spring loaded idle arm tensioner (2).
DO NOT OVERTIGHTEN - If
3. Insert and hand tighten the contact tip for use with
0.035” Innershield Flux Cored Wire.
4. Replace gas nozzle – The gasless nozzle may be
used instead of the gas nozzle to give improved visibility of the arc.
CHANGING DRIVE ROLL
The drive roll, Figure D.1 Item 1, has two grooves; one
for .023" – .025" (0.6 mm) solid steel electrode and a
larger groove for .030" (0.8 mm) solid and .035" (0.9 mm)
flux-cored steel electrode. As shipped, the drive roll is
installed in the .023"-.025" (0.6 mm) position.
If .030"/.035" (0.8/0.9 mm) wire is to be used, the
drive roll must be reversed as follows:
1. Turn the power switch to OFF (marked “O”).
2. Release the spring-loaded idle arm tensioner, Figure D.1
Item 2, and lift the idle roll arm,
from the drive roll.
3. Loosen the Phillips Head screw holding the drive
roll onto the drive shaft.
Figure D.1 Item 3,
away
3
2
1
FIGURE D.1
SP-125 PLUS
MAINTENANCE
1-1/4 (31.8 mm)
Liner Trim Length
D-4
CHANGING LINER
NOTICE: The variation in cable lengths prevents the interchangeability of liners. Once
a liner has been cut for a particular gun, it
should not be installed in another gun
unless it can meet the liner cutoff length
requirement. Refer to Figure D.2.
Gas Diffuser
SlottedBrass Cable
Set ScrewConnector
Liner Assembly
(Liner bushing to be seated tight
against brass cable connector)
Contact Tip
(Threaded)
Gas Nozzle or
Gasless Nozzle
(Threaded)
FIGURE D.2
Liner trim length for gun with red trigger (Magnum™ 100L)
1. Remove gun and cable assembly from
machine.
2. Remove the gas nozzle from the gun
by unscrewing counter-clockwise.
3. Remove the existing contact tip from
the gun by unscrewing counter-clockwise.
4. Remove the gas diffuser from the gun
tube by unscrewing counter-clockwise.
5. Lay the gun and cable out straight on a
flat surface. Loosen the set screw located in the brass connector at the wire
feeder end of the cable. Pull the liner
out of the cable.
6. Insert a new untrimmed liner into the
connector end of the cable. Be sure the
liner bushing is stenciled appropriately
for the wire size being used.
7. Fully seat the liner bushing into the
connector. Tighten the set screw on the
brass cable connector. At this time, the
gas diffuser should not be installed onto
the end of the gun tube.
8. With the gas nozzle and diffuser
removed from the gun tube, be sure the
cable is straight, and then trim the liner
to the length shown in the Figure D.2.
Remove any burrs from the end of the
liner.
9. Screw the gas diffuser onto the end of
the gun tube and securely tighten.
10. Replace the contact tip and nozzle.
SP-125 PLUS
D-5
MAINTENANCE
GUN HANDLE PARTS
The gun handle consists of two halves that are held
together with a collar on each end. To open up the
handle, turn the collars approximately 60 degrees
counter-clockwise until the collar reaches a stop. Then
pull the collar off the gun handle. If the collars are difficult to turn, position the gun handle against a corner,
place a screwdriver against the tab on the collar and
give the screwdriver a sharp blow to turn the collar
past an internal locking rib. See Figure D-3.
➣
Counter-clockwise
FIGURE D.3
SP-125 PLUS
TROUBLESHOOTING
HOW TO USE TROUBLESHOOTING GUIDE
Service and Repair should only be performed by Lincoln Electric Factory Trained Personnel.
Unauthorized repairs performed on this equipment may result in danger to the technician and
machine operator and will invalidate your factory warranty. For your safety and to avoid
Electrical Shock, please observe all safety notes and precautions detailed throughout this
manual.
This Troubleshooting Guide is provided to
help you locate and remedy possible
machine problems. Simply follow the threestep procedure listed below.
Step 1. LOCATE PROBLEM (SYMPTOM).
Look under the column labeled “PROBLEM
(SYMPTOMS)”. This column describes possible symptoms that the machine may
exhibit. Find the listing that best describes
the symptom that the machine is exhibiting.
Symptoms are grouped into the following
categories: Output Problems; Feeding
Problems; Gas Flow Problems; and
Welding Problems.
Step 2. PERFORM EXTERNAL TESTS.
The second column labeled “POSSIBLE
AREAS OF MISADJUSTMENT(S)” lists the
obvious external possibilities that may contribute to the machine symptom. Perform
these tests/checks in the order listed. In
general, these tests can be conducted without removing the case wrap-around cover.
Step 3. PERFORM COMPONENT TESTS.
If you have exhausted all of the recommended tests in Step 2, consult your local
Authorized Field Service facility.
CAUTION
If for any reason you do not understand the test procedures or are unable to Perform
the tests/repairs safely, contact your LOCAL AUTHORIZED LINCOLN ELECTRICFIELD SERVICE FACILITY for assistance before you proceed.
If machine case sides and top are removed, the case front must be supported.
Failure to do this could result in mechanical or electrical damage to the SP-125 Plus.
NOTE: This diagram is for reference only. It may not be accurate for all machines covered by this manual. The
specific diagram for a particular code is pasted inside the machine on one of the enclosure panels.
SP-125 PLUS
COMPOUND (DOW CORNING 340) WHEN REATTACHING.
F-2
NOTES
SP-125 PLUS
NOTES
SP-125 PLUS
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WARNING
Spanish
AVISO DE
PRECAUCION
● Do not touch electrically live parts or
electrode with skin or wet clothing.
● Insulate yourself from work and
ground.
● No toque las partes o los electrodos
bajo carga con la piel o ropa mojada.
● Aislese del trabajo y de la tierra.
● Keep flammable materials away.
● Mantenga el material combustible
fuera del área de trabajo.
● Wear eye, ear and body protection.
● Protéjase los ojos, los oídos y el
cuerpo.
French
ATTENTION
German
WARNUNG
Portuguese
ATENÇÃO
Japanese
Chinese
Korean
Arabic
● Ne laissez ni la peau ni des vête-
ments mouillés entrer en contact
avec des pièces sous tension.
● Isolez-vous du travail et de la terre.
● Berühren Sie keine stromführenden
Teile oder Elektroden mit Ihrem
Körper oder feuchter Kleidung!
● Isolieren Sie sich von den
Elektroden und dem Erdboden!
● Não toque partes elétricas e elec-
trodos com a pele ou roupa molhada.
● Isole-se da peça e terra.
● Gardez à l’écart de tout matériel
inflammable.
● Entfernen Sie brennbarres Material!
● Mantenha inflamáveis bem guarda-
dos.
● Protégez vos yeux, vos oreilles et
votre corps.
● Tragen Sie Augen-, Ohren- und Kör-
perschutz!
● Use proteção para a vista, ouvido e
corpo.
READ AND UNDERSTAND THE MANUFACTURER’S INSTRUCTION FOR THIS EQUIPMENT AND THE CONSUMABLES TO BE
USED AND FOLLOW YOUR EMPLOYER’S SAFETY PRACTICES.
SE RECOMIENDA LEER Y ENTENDER LAS INSTRUCCIONES DEL FABRICANTE PARA EL USO DE ESTE EQUIPO Y LOS
CONSUMIBLES QUE VA A UTILIZAR, SIGA LAS MEDIDAS DE SEGURIDAD DE SU SUPERVISOR.
LISEZ ET COMPRENEZ LES INSTRUCTIONS DU FABRICANT EN CE QUI REGARDE CET EQUIPMENT ET LES PRODUITS A
ETRE EMPLOYES ET SUIVEZ LES PROCEDURES DE SECURITE DE VOTRE EMPLOYEUR.
LESEN SIE UND BEFOLGEN SIE DIE BETRIEBSANLEITUNG DER ANLAGE UND DEN ELEKTRODENEINSATZ DES HERSTELLERS. DIE UNFALLVERHÜTUNGSVORSCHRIFTEN DES ARBEITGEBERS SIND EBENFALLS ZU BEACHTEN.
● Keep your head out of fumes.
● Use ventilation or exhaust to
remove fumes from breathing zone.
● Turn power off before servicing.
● Do not operate with panel open or
guards off.
WARNING
● Los humos fuera de la zona de res-
piración.
● Mantenga la cabeza fuera de los
humos. Utilice ventilación o
aspiración para gases.
● Gardez la tête à l’écart des fumées.
● Utilisez un ventilateur ou un aspira-
teur pour ôter les fumées des zones
de travail.
● Vermeiden Sie das Einatmen von
Schweibrauch!
● Sorgen Sie für gute Be- und
Entlüftung des Arbeitsplatzes!
● Mantenha seu rosto da fumaça.
● Use ventilação e exhaustão para
remover fumo da zona respiratória.
● Desconectar el cable de ali-
mentación de poder de la máquina
antes de iniciar cualquier servicio.