Longevity 444528 Instructions / Assembly

Operating Manual
for
250 Amp AC/DC Pulse IGBT TIG Welder With PFC Technology
TIGWELD® 250 EX
Table of Contents
Table of Content
Pg. 1
Thank you From LONGEVITY
Pg. 2
Warranty/Shipping Damage/Order Information
Pg. 3
Safety Information
Pg. 4-5
Specifications and Ratings
Pg. 7-8
Main Unit Knob/Button/Function Diagram
Pg. 9-10
TIG Pulsing
Pg.11
TIG Section: Torch Assembly
Pg. 12
Selecting the Right Tungsten
Pg. 13-14
Selecting the Right Filler Rods
Pg. 15
Argon Regulator Installation
Pg. 16
Basic TIG Operation
Pg. 17-20
Basic Stick/Arc Welding Operation
Pg. 21-25
Routine Maintenance
Pg. 26
Troubleshooting
Pg. 27
THANK YOU!
www.longevity-inc.com
1
TIGWELD® 250 EX
We, at LONGEVITY, want to thank you for purchasing our product. You are almost ready to
experience Longevity Welding first hand. Longevity definitely appreciates your business and
understand that this equipment may be overwhelming to setup and operate so we have prepared a
manual that will assist you in understand your new plasma cutter/welder. If you have any
questions during or after reading this manual, please feel to contact us! Please take a moment to
register your product on our website at www.longevity-inc.com or www.lweld.com
Once again, thank you for choosing Longevity as your main welding supplier!
Longevity Global, Inc
23591 Foley St
Hayward, CA 94545
Toll-Free Customer Support: 1-877-LONG-INC / 1-877-566-4462
Website: www.longevity-inc.com
Sales: sales@longevitywelding.com
Customer Service: help@longevity-inc.com
Dealers: dealers@longevity-inc.com
Complaints: complaints@longevity-inc.com
Please join our welding forums to share welding tips and tricks, to receive useful information
from customers who also use our products, and to be a part of the Longevity™ welding
community at www.freeweldingforum.com
www.longevity-inc.com
TIGWELD® 250 EX
Warranty
LONGEVITY Plasma Cutters, Welders, and Multi-Purpose Welders are covered for specific Parts
and Labor warranty at our facility. For detailed information regarding your specific LONGEVITY
welder or cutter, please view our Terms and Policies page on our website at the following website
link: http://www.longevity-inc.com/terms/
Shipping Damage
Your machine is insured against damage during shipping. Keep all packing materials and containers
in case machine must be returned. We will initiate a claim with the shipping company to cover
damage or loss. If there is shipping damage upon opening your package, our customer service team
will work with you to get the matter resolved.
In Warranty Service
Customers, who own machines that are in warranty and require service, should contact our Warranty
Department by email at help@longevity-inc.com to obtain a return authorization code. In addition to
the warranty we offer, we would like for you to register your product on our website at
www.longevity-inc.com/resources. Remember, warranty starts from the date of purchase. For your
convenience, write your order information below so you can track your order in case you need
warranty work.
Order No.: _________________________________
Date of Purchase: _____________________________
Warranty Period: ______________________________
Out-of-Warranty Service
Customers, who own machines that are out of warranty and require service, should contact us for an
estimate. Longevity offers an exchange program on out of warranty units. We also help non
LONGEVITY customers with repairs, replacement, and service.
If your unit is not manufactured by Longevity and you cannot receive service from your manufacturer or
seller, Longevity will lend out hand. Our warranty policy is also available for all plasma cutters and
welders. For more information, please email us at
HELP@longevity-inc.com
www.longevity-inc.com
3
TIGWELD® 250 EX
Warnings and Safety















Welding and plasma cutting may be dangerous to the operator and to bystanders, if the
equipment is not operated properly. Welding or cutting must be performed in accordance
with all relevant safety regulations. Carefully read and understand this instruction manual
before installing and operating this equipment.
Changing function modes during welding may damage
equipment.
Before welding, disconnect the electrode-holder cable
from the equipment.
A circuit breaker is required to prevent electrical
overload of the equipment.
Only high quality welding tools should be used.
Electric Shock can be fatal.
Ensure that ground cable is connected in accordance with
applicable safety codes.
Never touch electrodes, wires, or circuit components with
bare hands. Wear dry welding gloves when welding.
The operator must be insulated from the work piece.
Smoke and gas can be harmful to health.
Ensure that the working area is well ventilated.
Avoid breathing smoke and gas generated during the
welding process. Cutting and welding can cause cancer
because of the smoke that comes from the welds and cuts.
Arc-light emission can be harmful to eyes and skin.
Always wear a welding helmet, anti-radiation glass, and
work clothes while welding.
Ensure that people in or near the working area are
protected.
Welding splash is a fire hazard.
Keep flammable material away from the work place.
Keep a fire extinguisher nearby, and have all personnel
trained in it’s use.
Surface noise generated while welding or cutting can be
harmful to hearing.
In the event of a machine fault.
Refer to this instruction manual.
If the fault cannot be determined, contact your local
dealer or supplier for assistance.
www.longevity-inc.com
TIGWELD® 250 EX
Safety Tips
Consider the following tips to ensure safe operation of your welding/cutting equipment:


Ensure that this welding equipment is installed in an area free of corrosive chemical gases,
flammable gases or materials, and explosive chemicals.
The area should contain little dust, and have a humidity of no more than 80%.

Operate the welding equipment in an area sheltered from direct sunlight and precipitation.
Work area temperature should be maintained at -10C to +40C;

If, because of an overload, the machine suddenly stops, and it is necessary to restart it, leave
the internal fan operating to lower the inside temperature.

Always wear protective clothing and a welding mask to protect your skin.

Wear safety goggles designed to darken the arc generated by your machine.

Wear suitable noise protection to protect your hearing.

Ensure that machine is grounded through the power cord or on the machine case.

Never operate the machine in bare feet or on a wet floor.

Never switch the machine off while it’s in use. Doing so will damage the internal circuitry.

Ensure that your circuit breaker is rated to handle the current requirements of your machine.

Use a UL approved receptacles and plugs with your machine. Never hard wire the machine to
main power.

Work in a well ventilated area to avoid smoke. Keep your head out of the smoke. Ensure that
air is flowing away from you to avoid inhaling smoke.

Ensure proper ventilation through the machine’s louvers. Maintain a distance of at least
12 inches between this cutting equipment and any other objects in the work area.

Use a screen or curtain designed to keep passers by from viewing the arc.

The arc spray and metal spray from machine use may cause nearby fires. Use caution.

If, after reviewing this manual, you have any problems in setting up or operating your
machine, contact us at help@longevity-inc.com.
www.longevity-inc.com
5
TIGWELD® 250 EX

Main Unit

Amp Adjust TIG Torch and TIG Torch Pieces

Stick Electrode Holder

Foot Pedal

Ground Clamp

Air Hose and Ground Clamp
*Not pictured

Argon Regulator
*Different then pictured.
www.longevity-inc.com
TIGWELD® 250 EX
Techinical Specifications and Ratings
MODE
TYPE
PARAMETER
TIGWELD® 250 EX
TIGWELD® 250 EX
Power Voltage
1Phase, 110/220v ±15%
Input Frequency
50/60 Hz
Inverter
IGBT
Protection Class
IP23
Weight
49 lb
Size (unit only)
L: 19.6 in x H: 15.25 in x W: 9.25 in
(AC) 10-250 A
AC TIG
Output
(DC) 5-250 A
DC TIG
Arc Starting Mode
HF / Lift-TIG
220v
35% @ 250 A
60% @ 210 A
100% @ 190 A
Rated Duty Cycle at Max Amps
110v
35% @ 120 A
60% @ 110 A
100% @ 100 A
Max Amps
10-250 A
220v
STICK
35% @ 160 A
60% @ 130 A
100% @ 100 A
Rated Duty Cycle at Max Amps
110v
35% @ 100 A
60% @ 90 A
100% @ 80 A
www.longevity-inc.com
7
TIGWELD® 250 EX
Weld Method
Parameter
STICK
HF TIG
LIFT TIG
Pre Flow
0.1-9.9s
NO
YES
YES
P.P. Current
5-
NO
YES
YES
Post Gas
0-25s
NO
YES
YES
Up-Slope Time
0-10s
NO
YES
YES
Down-Slope Time
0-10s
NO
YES
YES
Pulse Frequency (DC
TIG)
0.5-500Hz
NO
YES
YES
Pulse Wide Range (AC
TIG)
0.5-10Hz
NO
YES
YES
Cleaning Effect
+30% -30%
NO
YES
YES
I/Hot
0-2s
NO
YES
YES
Arc Force
0-100%
NO
NO
NO
0-100%
NO
NO
NO
T/Hot
www.longevity-inc.com
TIGWELD® 250 EX
DECRIPTION OF CONTROL PANELS
No.
FUNCTION
1
Pre-Flow Indicator
2
Starting Amp Indicator
For TIG Welding
3
Upslope Time Indicator
Period in TIG welding during which the starting current is increased to the
specified main current
4
Welding Amps Indicator
Main Amps
5
Peak Amp Indicator
Pulse Peak Amps (1-100%)
6
Downslope Time Indicator
Period in TIG welding during which the specified main current I1 is lowered
to the final currentI
7
Ending Amps Indicator
For TIG Welding
8
Argon Stopping Indicator
For TIG Welding
9
Foot Switch Indicator
Lights up if foot switch is connected
10
Hot Start
For Stick Welding
11
Arc Force
For Stick Welding
12
TIG AC Welding Indicator
ON/OFF
13
TIG DC- Indicator
14
TIG DC+ Welding Indicator
www.longevity-inc.com
DESCRIPTION
9
TIGWELD® 250 EX
15
Rectangle Wave Indicator
16
Sine Wave Indicator
17
Square Wave Indicator
18
Triangle Wave Indicator
19
Pulse ON Indicator
20
Pulse OFF Indicator
21
Gas Test Indicator
22
TIG Mode
23
Stick Mode
24
2-Step Mode Indicator
25
4-Step Mode Indicator
26
Pulse Mode Indicator
27
HF Contact Indicator
28
Lift-TIG Indicator
29
Power Indicator
ON/OFF
30
Thermal Overload Indicator
Lights up If the power source overheats (e.g. because the duty cycle has been
exceeded). For more information on this, see the "Trouble shooting" section.
ON/OFF
When the Machine shuts down the yellow light will blink and the data will
be saved.
31
Hot Start
32
Hot Time
33
AC Frequency
34
Parameter Adjustment Knob
Used to adjust welding parameter.
35
Balance
(-30%/+30%)Used to set the cleaning action for TIG AC welding.
36
Parameter Select Left
37
Parameter Select Right
38
Amps
39
Output Amps
40
Memory Display
Memory display 1-9.
41
Store Button
Used to store of to 9 different settings.
42
Polarity Select
43
Wave Form Selector
44
Pulse Selector
45
Gas Test Button
46
Process Button
47
Mode Button
ON/OFF
48
HF Contact Button
Select Lift-TIG or HF Start.
Used to select wave form (Triangle, Sine, OFF or Rectangle)
Used to set the required amount of shielding gas at the pressure regulator.
After you press this button, gas will flow out for 30s. Press the button again
to stop the test gas flow before the 30seconds are up.
www.longevity-inc.com
TIGWELD® 250 EX
TIG pulsing
The welding current set at the start of the welding procedure is not necessarily ideal for all
welding process:
- if the current is too low, the base material will not melt sufficiently,
- if overheating occurs, the liquid weld pool may drip.
The TIG pulsing function offers a solution (TIG welding with pulsing welding current): a low
base current I-G rises steeply to the significantly higher pulsing current I1 and, depending on the
set dcY (duty cycle) time, drops back to the base current I-G. In TIG pulsing, small sections of
the welding location melt quickly and then solidify again quickly.
In manual applications using TIG pulsing, the filler wire is applied in the maximum current
phase (only possible in the low frequency range: 0.25 - 5 Hz). Higher pulsing frequencies are
mainly used in automatic mode to stabilize the arc.
TIG pulsing is used for out-of-position welding of steel pipes or when welding thin sheet.
Mode of operation of TIG pulsing when TIG DC welding is selected:
Legend:
- IS Starting current
- IE Final current
- tUp Upslope
- tDown Downslope
- F-P Pulsing frequency
(1/F-P = time interval between 2
pulses)
- dcY Duty cycle
- I-G Base current
- I1 Main current
www.longevity-inc.com
11
TIGWELD® 250 EX
TIG Section: Setting Up The TIG Torch
www.longevity-inc.com
TIGWELD® 250 EX
Selecting the Right Tungsten Electrodes:
Selecting the right tungsten is crucial to a successful TIG weld. You have to insure the correct
tungsten is used for the type of metal you are welding, the type of technology used in your
welder such as transformer or inverter, and the thickness of the metal you will need to weld. This
leaves you with a variety sizes ranging from 1/16 to 1/8” and the types of tungstens such as the
Pure Tungsten (TP), 2% Thoriated Tungsten (TT2), 2% Ceriated Tungsten (TC2), and 2%
Lanthanated Tungsten (TL2). Fortunately, LONGEVITY offers high quality tungsten electrodes
and explains which tungsten is required for the right application. Pure Tungsten (TP) – (green
tipped) - Pure tungsten readily forms a ball on the end. It is designed for use with transformerbased power sources for AC welding of aluminum. Unfortunately, LONGEVITY does not carry
transformer based technology considering the size and weight of TRANSFORMER welders.
Therefore, this tungsten is rarely sold buy our sales staff
2% Thoriated Tungsten (TT2) – (red tipped) - This tungsten is the most common tungsten
currently being used with LONGEVITY DC TIG. It is generally utilized for DC welding of mild
steel, bronze, and stainless steel and basically all metals except aluminum and offers excellent
performance. A drawback is that this tungsten has a low level radiation hazard and the fact that
they no recommend to weld aluminum. We recommend this tungsten with our stand alone DC
only TIG Welders, our TIGWELD 250 EX multi-process welders, which feature DC TIG
welders. The 2% Thoriated Tungsten works well with Inverter Welders. This is the tungsten to
use for your welder. LONGEVITY does have them available.
2% Ceriated Tungsten (TC2) – (grey tipped) – 2% ceriated is an excellent substitute for 2%
thoriated tungsten and is designed for transformer and inverter based power sources. For
Transformer DC welding, this tungsten requires less amperage to start so it is recommended for
thinner metals. It offers a stable arc and can be used for both AC and DC welding with inverter
power sources and is our most popular sold tungsten because it can be used to weld every type of
metal in both AC / DC modes in our LONGEVITY INVETER TIG welders. We recommend this
unit with our TIGWELD 250 EX 250AMP ACDC TIG/STICK unit or our INNOVATOR series
multi functional welders and plasma cutters because of the versatility of AC DC welding.
2% Lanthanated Tungsten (TL2) – blue tip – 2% lanthanated is probably the most popular
substitute for 2% thoriated tungsten. Offering a longer life span than the 2% thoriated tungstens,
it is a nice a nice alternative, but not as recommended as our 2% Thoriated Tungsten. This
tungsten can be used with both transformer and inverter technology on both AC DC modes.
www.longevity-inc.com
13
TIGWELD® 250 EX
Tungsten Chart Guide
Tungsten Type Diameter
040"(1.0mm)
1/16"(1.6mm)
3/32"(2.4mm)
1/8"(3.2mm)
Pure Tungsten
TP-7040
TP-7116
TP-7332
TP-718
2% Thoriated
TT2-7040
TT2-7116
TT2-7332
TT2-718
2% Ceriated
TC2-7040
TC2-7116
TC2-7332
TC2-718
2%
Lanthanated
TL2-7040
TL2-7116
TL2-7332
TL2-718
Amparage-Ac
20-30
30-80
60-130
120-200
Amparge-Dc
15-50
50-120
80-150
130-250
Sharpening a Tungsten
Sharpening a tungsten is very important for a nice fine arc strike. There are auto sharpeners to
place the perfect sharpening point on your tungstens or you can simply use a grinding wheel to
sharpen your tungsten. Remember, after sharpening to a pencil point, you want to flatten the
bottom for a good arc.
www.longevity-inc.com
TIGWELD® 250 EX
Selecting the right FILLER RODS FOR TIG WELDING:
Filler Rods are essential to TIG Welding because the filler rod is fed into the molten puddle by
hand filling in the puddle to create a stronger metal bond or puddle to join two metal pieces. It is
extremely important to have the right filler rod based on the metal you are welding. It is also
necessary to have the right tungsten to insure you are properly setup to weld your metal.
Part #
Application:
4043-1/16-1 4043 Alloy Aluminum Wire
1/16" X 36"
4043-3/32-1 4043 Alloy Aluminum Wire
3/32" X 36"
5356-1/16-1 5356 Alloy Aluminum Wire
1/16" X 36"
5356-3/32-1 5356 Alloy Aluminum Wire
3/32" X 36"
308L-035-1 308L Stainless Steel Wire
.035” x 36”
308L-1/16-1 308L Stainless Steel Wire
1/16" X 36"
70S6-1/16-1 ER70S-6 Steel Wire
1/16" X 36"
70S6-3/32-1 ER70S-6 Steel Wire
3/32" X 36"
70S2-1/16-1 ER70S-2 Steel Wire
1/16" X 36"
80SD2-1/16ER80SD-2 Steel Wire
1
E1/16" X 36"
Longevity offers quality filler rods at affordable prices. Please take a look at the selection of
filler rods that we carry to decide what the best application of rod will be for your weld.
Your choice of filler rod is extremely important to the strength and matter density of your weld.
You can determine the diameter of the filler rod needed, by the thickness of the material that you
will be welding. Here are some pointers in deciding how to choose the correct filler rod for your
weld.
1. 4043 is a general filler rod for most aluminum welding. Remember, the TIGWELD 250
EX is strictly DC welding so aluminum is not possible with the use of Argon.
2. 5356 is perfect for 5xxx series aluminum. If you are planning on anodizing the finished
piece, this rod should be used for the weld.
3. ER70S-6 is designed for welding mild steel.
4. ER70S-2 is recommended for welding 4130 chrome moly tubing in most applications.
www.longevity-inc.com
15
TIGWELD® 250 EX
5. ER80S-D2 is for welding 4130 chrome moly tubing if a higher strength weld is required.
6. 1/16” diameter filler should be used when material is 1/8” and less thick. 3/32” diameter
filler rod can be used for 1/8” and thicker material. For more info on Filler Rods, go to
www.freeweldingforum.com
Setting Up the Argon Regulator:
The argon regulator (pictured below) is included with your unit. Setting it up to your
argon bottle is easy. Simply screw in the valve to the bottle and set the pressure to
about. Use 100% Argon at 15-25 CFH (cubic feet per hour). Set the gas flow using the regulator
on the gas bottle. Use higher flow when extending the tungsten electrode to reach into corners or
gaps. We recommend about 18 CFH. Remember, that you also have a post flow setting on the
unit to pass more argon after the arc to cool the electrode.
Argon Regulator Assembled.
*argon regulator may not be the same as pictured.
www.longevity-inc.com
TIGWELD® 250 EX
Basic TIG Operation
(Tungsten Inert Gas - Gas Tungsten Arc Welding - GTAW)
TIG Operation and Principles:
Shielding Gas: Use 100% Argon at 15-25 (cubic feet per hour). Set the gas flow using the
regulator on the gas bottle. Use higher flow when extending the tungsten electrode to reach into
corners or gaps.
Tungsten Electrode: We recommend 2% Thoriated tungsten (red) for TIG welding with our DC
TIG welders. Use smaller diameter electrodes for thinner metal (low amperage), thicker
electrodes for thicker metals that require more amperage. For the right tungsten electrode, please
refer to earlier in this manual or go to www.longevity-inc.com
Filler Rod Selection: Depending upon the metal to be welded, filler rod selection is critical.
Consult with your local welding supplier for the optimum filler rod to properly complete the
weld. In certain applications, TIG welding can be performed without the use of a filler rod. Use
free welding forum at www.freeweldingforum.com to gather advice or go to www.longevityinc.com.
Pre-TIG Welding
As you get to know the above information of basic TIG welding applications, there are a couple
of basic steps that need to be taken. The tungsten must be sharpened and shaped before initiating
an arc. With inverter TIG welding machines, tungsten sharpness is important. Your weld’s
outcome will be partially determined by the shape of your tungsten. Sharpening an electrode
consistently will cause an unstable, wandering arc, making it more difficult to control the weld
puddle. Carefully rotate the tungsten as it is being ground to prevent a flat spot or a hollow
ground point. Also note that tapering the tungsten to 2.5 times of its diameter is generally
recommended for most DC welding applications. For high amperage DC welding, do not over
sharpen the point, but leave a slight truncation on the end of the tungsten. This prevents the
tungsten tip from breaking away and falling into the weld. It is also normal for a slight dome to
form on the tungsten in DC mode. However, if the arc becomes erratic or the arc is difficult to
start, regrinding the tungsten will be necessary. If the tungsten is accidentally dipped into the
weld puddle, regrinding the tungsten will be necessary to eliminate contamination, particularly
on aluminum. Grind tungsten’s only on a dedicated stone, free of contamination from other
metals.
www.longevity-inc.com
17
TIGWELD® 250 EX
Starting a TIG Weld: Filler rod selection is critical to a TIG welds density, strength and purity.
Check out our filler rod selection chart on our website for optimum filler rod to properly
complete a weld. In certain applications, TIG welding can be performed without the use of a
filler rod. One of the biggest issues for beginning welders is holding and maintaining an arc.
Starting an arc with your High Frequency welder is quite simple. Set the machine for TIG
operation then select the desired amperage. Grasp the torch in a manner that is comfortable to
you. Place the torch so that the tungsten is no more than 1/8 inch from the weld surface.
Depending upon the setup, either press the foot pedal down or press the trigger to initiate the
high frequency arc. A small blue glowing cone may be observed. This is the high frequency arc.
Immediately after that, you should see a strong and stable arc flowing from the torch. As the arc
begins to grow, a molten puddle will appear. If it does not appear, stop your weld and increase
the amperage. Repeat the start sequence.
1. To help the molten puddle form, slowly make small circles with the torch to build the heat in
the weld area. A bright, fluid puddle will begin to form.
2. Once a uniform puddle is established, tilt the torch head about 75 degrees from the weld
surface into the direction of the weld. This will direct the arc to the front of the weld puddle.
3. Grip the filler rod at a 15 degree angle to the weld surface with the other hand. Hold the rod in
the iridescent cone of gas that surrounds the weld puddle. Do not hold it in the arc. Keep it close
to the weld. A “skeleton” keyhole will begin to form in front of the weld. The keyhole is
evidence that you are ready to add filler material and move forward. Introduce the filler rod into
the key hole area underneath the arc. Wait for a single molten drop to fall off the tip of the rod.
4. When a molten drop falls from the rod, quickly remove the rod, keeping it inside the gas cone.
The molten drop of filler metal should blend quickly into the puddle.
5. Move the torch forward slightly, carrying the keyhole with the weld. If the key hole is lost,
then forward travel was too fast or too far. When the keyhole shows good development, repeat
the steps 3-5 until you have a proper weld bead established.
6. Weld termination. When the weld bead has reached the desired length, add a final drop of
filler and slowly circle the torch over the end of the weld to fill the crater. If the weld crater is not
correctly filled, cracking and weld failure may occur. This is a small but important step to
properly completing a weld. Release the foot pedal or release the trigger to stop. Keep the TIG
torch in place until the post flow ends--usually around 5 seconds.
7. When finished welding always let the welder's fan run for a minute or two to cool the machine
before turning the power switch off.
Basic Diagrams of Welding
Fig.1
Figure 1: Comparison chart of welds
Fig. 2
www.longevity-inc.com
TIGWELD® 250 EX
Length of Arc When an arc is too long, the metal
melts off the electrode in large globules and the arc may break frequently. This produces a wide,
spattered, and irregular deposit with insufficient fusion between the base metal and the weld.
When an arc is too short, it fails to generate enough heat to melt the base metal properly, causes
the electrode
Fig. 3
Setting the length of an arc to stick frequently to the base
metal, and produces uneven deposits with irregular ripples. The recommended length of the arc
is equal to the diameter of the bare end of the electrode, as shown in figure 3.
The length of the arc depends upon the type of electrode and the type of welding being done;
therefore, for smaller diameter electrodes, a shorter arc is necessary than for larger electrodes.
Remember: the length of the arc should be about equal to the diameter of the bare electrode
except when welding in the vertical or over- head position. In either position, a shorter arc is
desirable because it gives better control of the molten puddle and prevents atmospherical
impurities from entering the weld.
www.longevity-inc.com
19
TIGWELD® 250 EX
Sample of a quality stainless steel weld:
TALLATION
www.longevity-inc.com
TIGWELD® 250 EX
STICK/ARC Welding
Stick Welding
(Also known as MMA-Manual Metal Arc or Shielded Metal Arc WeldingSMAW)
Connect the Stick torch to the - terminal and Torch Control receptacles.
Connect the ground clamp to the + terminal and clamp the metal to be welded. Reverse the torch
and ground connections for DCEP (Direct Current Electrode Positive).
DC Stick - Select Stick, DC, desired amps using Base cur knob
1. Insert electrode into electrode holder. Position the electrode for the most comfortable position so
that the electrode can be held directly over the work piece with a slight angle.
2. Set Amperage to the recommended amperage by the electrode manufacturer. Strike an arc by
swiping it briskly across the work piece in the same manner as one would strike a match.
Alternatively, you may strike an arc with firm tapping motion against the work piece. Either
method is acceptable. An arc should initiate. Continue to keep the arc going by holding the
electrode off the work piece no more than the electrode width.
3. Continue the arc by feeding the electrode into the weld puddle while moving the electrode
forward. This will take some coordination, but will be fairly easy to do after practice. Do not allow
the arc to become too long, because air and slag can become entrapped in the metal. The sound of a
proper arc will be similar to a gentle frying sound. A long arc will emit a humming sound. An arc
that is too short may be extinguished and the electrode may stick to the work piece. If the electrode
sticks, immediately release the electrode from the electrode holder and break the electrode loose by
hand. If the flux breaks off, simply trim off the excess rod until flux and bare metal meet. A
welding rod must have flux to shield the weld from the atmosphere or the weld will fail.
4. Use the Basic Current control to change arc qualities. Adjust the amperage according to the
recommendations of the electrode (welding rod) manufacturer for the type and size of the electrode
used. When welding in the AC mode the AC Frequency control will affect how crisp the arc is,
whether it is smooth and buttery or deeply penetrating. Use it to suit the desired weld finish.
www.longevity-inc.com
21
TIGWELD® 250 EX
Experimentation will be required to find the optimal setting desired. It is an excellent tool for out
of position welding.
5. Electrode selection. Electrodes are usually given performance and characteristic ratings using a
system of letters and numbers determined by the American Welding Society (AWS). The rating
system includes the minimum tensile strength of the finished weld, the weld position (flat, vertical,
horizontal, or overhead or a combination of two or more positions) and the flux type. Additional
information may be given. Each manufacturer has their individual name and terminology as well.
As there is no general recommendation that can be made about a particular electrode selection,
except for practice welds, a electrode designated by the AWS as E 6011, E 6013, E 7014, or E
7018 may be used, each having its own distinct features and purpose. These are among the most
common electrodes used in the industry and are not difficult to find. E 6011 electrodes are not as
smooth running as some of the other electrodes, but offer the advantage of being able to weld on
rusty metal and contaminated surfaces. It is widely used and requires very little skill to begin
using. This is not a particular endorsement of an E6011, rather a simple example of what may be
used in developing proficient technique. It is recommended that a variety of electrodes be used and
practiced with. Consultation with an experienced local welding supplier will help greatly in
determining what welding electrode is the best for your given situation. Many times, samples or
small packages of electrodes are available at relatively low cost to determine for yourself the best
electrode to use.
Stick Electrode Chart Example: E 60 1 3
Strength
60--60,000 psi,
70--70,000 psi
Weld Position
1--All positions: Flat, Vertical, Horizontal, & Overhead
2--Flat Position or Horizontal Fillets Only
3--Flat Position Only
Weld Characteristics
0--Non-low hydrogen, DC Reverse polarity
1--Non-low hydrogen, AC or DC Reverse polarity
2--Non-low hydrogen, AC or DC Straight polarity
3--Non-low hydrogen, AC or DC Either polarity
4--Non-low hydrogen, iron powder coating, AC or DC Reverse polarity
5--Low-hydrogen, DC Reverse polarity
6--Low-hydrogen, AC or DC Reverse polarity
7--Non-low hydrogen, iron powder coating, AC or DC Reverse polarity
8--Low hydrogen, iron powder coating, AC or DC Reverse polarity
Polarity Definition
electrode negative =straight polarity (typical stock machine setup)
electrode positive = reverse polarity
Be sure to observe the electrode manufacturer recommendations regarding polarity. If the weld
appears lumpy, porous or otherwise malformed, change the polarity of the ground cable and the
www.longevity-inc.com
TIGWELD® 250 EX
electrode holder cable. Many electrodes run with in reverse polarity, (DCEP) setting. A few run
with a straight polarity (DCEN). Some will run either way. For reverse polarity (DCEP) stick
welding, swap the electrode holder and ground cable connections.
Proper weld identification. Overlap and undercutting are two main causes of weld failure. Proper
washing of the weld bead into the sides or “toes” of the weld is important. Keep the welding
electrode or the TIG tungsten and welding arc within the weld joint to prevent overlap. Pausing on
the sides of the welds to wait for the sides to fill reduces the chance of undercutting, even if the
current is a little too high. If it is possible, with any practice weld, cut the joint down the middle,
lengthwise, or place the weld in a vice and use a hammer to bend the metal over the weld area until
it is either broken or bent 90 degrees. This destructive testing method will help you improve your
skill by revealing faults and flaws in your welds.
Stick (SMAW)Electrode Welding
Stick, the most basic of welding processes, offers the easiest option for joining steel and other metals. Although
it produces the least pretties or cleanest welds, ARC/STICK welding gets the job done! Stick welding power
sources deliver inexpensive options for welding versatility, portability and reliability. Stick joins metals when
an arc is struck between the electrode and the work piece, creating a weld pool and depositing a consumable
metal electrode into the joint. The electrode's protective coating also acts as a shielding gas, protecting the weld
and ensuring its purity and strength. Best for windy conditions and adverse environments.
If you’re not familiar with Stick (SMAW) welding basics, the following information can make choosing
an electrode easier.
AWS
Class
E6010
Position
All
E6011
All
E6013
All
E7014
All
E7018
All
Polarity
Usage
A great choice for welding on dirty, rusty, greasy or painted steel - especially in
vertical or overhead applications.
All-purpose stick electrode; used for carbon and galvanized steel; 60,000 PSI tensile
AC,DCEP
strength; deep penetration and ideal for welding light to medium amounts of dirty,
rusty or painted materials.
Light to medium penetrating all-purpose stick electrode; for use on carbon steel;
AC,DCEN,DCEP 60,000 PSI tensile strength; good for general all-purpose applications and joints
with poor fit-up.
For higher-deposition requirements; 70,000 PSI tensile strength; ideal for
AC,DCEN,DCEP
applications requiring light penetration and faster travel speeds.
Low-hydrogen electrode; for low, medium and high-carbon steels; 70,000 PSI
DCEP
tensile strength; ideal for out-of-position welding and tacking; not recommended for
low-voltage AC Welders.
DCEP
E7018AC
All
AC,DCEP
www.longevity-inc.com
Low-hydrogen electrode; for low, medium and high-carbon steels; 70,000 PSI
tensile strength; ideal for out-of-position welding and tacking; specially formulated
to operate with small 208/230 volt AC welders.
23
TIGWELD® 250 EX
www.longevity-inc.com
TIGWELD® 250 EX
Helpful Hints
 Use a drag technique for most applications.
 Take precautions with flying materials
when chipping slag.
 Keep electrodes clean and dry - follow
manufacturers instructions.
 Common steel electrodes (refer to chart
above).
 Penetration: DCEN- Less penetration; AC
- Medium (can be more spatter also); DCEP Most penetration
Catalog and Capabilities
LONGEVITY has what you need for stick welding,
from welders to welding supplies and protective
clothing. Stick welders come in two basic
classifications; 115V stick welders and 230/460V
stick welders. Stick Electrodes or welding rod for
stick welding are available in stainless steel, carbon
steel, low alloy steel, maintenance alloy, hard facing,
nickel alloy, and magnesium
www.longevity-inc.com
25
TIGWELD® 250 EX
Routine Maintenance
The life of your machine and the quality of the work performed using your machine, will be
enhanced by practicing periodic routine maintenance.

At regular intervals, clear dust that may accumulate in the machine using clean and dry
compressed air. If the working condition has heavy smoke and pollution, the welding machine
should be cleaned once a month.

Keep the machine exterior clean with mild soap and water.

Do not walk on or store items on the cables or cords.

Do not jar, drop, or stack items on top of the machine.

Always connect the machine to a well grounded electrical outlet.



Always check the torch consumables before and after use and ensure that they are clear
of obstructions, and that no parts are damaged.
Replace any worn or damaged consumables before using machine.
For periods of prolonged non-use, remove cables and store them in their original boxes in
a cool dry place, free of bug infestation.
www.longevity-inc.com
TIGWELD® 250 EX
Troubleshooting
If your unit is not properly functioning, please call us immediately toll free at 1-877-566-4462
for support. We have included a small table here to diagnose most common problems.
Problems, Causes, and Solutions
Causes/
Solutions
Problems
Machine will not turn

on.
The machine runs, but

nothing is happening

O.C. Over Current
LED Lights
Issue Not Listed


Unit Will Not Weld
Tungsten is Melting or

Being Consumed
Quickly
Contaminated

Tungsten

Poor Weld Quality
STICK Welder

Having a Hard Time
Striking an Arc
STICK Welder
Producing Poor

Quality Welds
www.longevity-inc.com
Check cords and breaker. If nothing is found, contact LONGEVITY
Check to see if you are in the right mode tig or stick. Check the torches and
your ground.
The unit has reached its DUTY Cycle. Leave power of the machine on and
allow fans to cool the machine. You can also turn the machine off to properly
cool it. Do not continue to weld until light is off.
Contact LONGEVITY Toll Free 1-877-566-4462 or via email at
help@longevity-inc.com
Check ground connection, torch setup, and check if you are in the proper
mode ARC/TIG. If you are TIG Welding check to see if you have the proper
TUNGSTEN and FILLER ROD.
Low Argon Gas flow. Check the Argon Gas flow. Turn up post flow.
Incorrect Tungsten or Incorrect Tungsten Size. Possible small size shield cup.
Read selecting the right tungsten on www.longevity-inc.com/resources
If the Tungsten is dipping or melting inside the weld. Use larger tungsten
and fewer amps on the unit. Sharpen tungsten.
Remember to clean welding material prior to welding with acetone. Practice
on the form and technique. Use the right tungsten and filler rod.
Check the ground. Check the workpiece and clean it. Increase the Arc Force
on the unit.
Use the proper rod and polarity.
27