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Component Identification and Explanation
SELECT THE PROPER TUNGSTEN TYPE.
TUNGSTEN SELECTION
Selecting the correct tungsten for your TIG welder is important.
While Thoriated 2% Tungsten can be used in an inverter for DC
welding, it is falling out of favor in the industry due to the slight
radioactive nature of it. But as of now it is still an industry standard
in North America. It should be noted that it has already been banned
in some countries. Check your country or regions policy on Thoriat-
ed Tungsten. Other types are quickly becoming available every-
where. Call your local welding supplier or check online for sources.
For TIG welding with DC consider the following types.
•
Lanthanated 2% (Blue Band). Overall this is one of the best
choices for TIG welding and can be used for AC and DC weld-
ing. It has great arc starting characteristics, and its point hold-
ing capability is excellent.
•
Ceriated 2% (Gray Band or Orange Band, depending upon
brand and country of origin). This is a good choice for welding
with both AC and DC, but doesn't hold up as well and starts to
erode faster than Lanthanated at higher amperages. But arc
starting is excellent.
•
Lanthanated 1.5% (Gold Band). Holds up nearly as well as
Lanthanated 2% and can be used for AC or DC welding. In
some tests it has rivaled Lanthanated 2% performance.
•
Tri-Mix/Rare Earth (Purple Band or Turquois Band). Still rela-
tively new. Some swear by it, and is being marketed as a re-
placement for Thoriated 2%. Overall, it does perform fairly well
and even excels in many circumstances. But some problems
have been seen with quality control. The primary metal oxide
used is lanthanum 1.5%. Usually it also includes a small per-
cent of Zirconium and Cerium to complete the mix. Some use
Yttrium. But the balance of the composition blend are usually
stated to be around .06 to .08%, but can be allowed to vary up
or down from .04% to .01%, making he blend prone to incon-
sistency in quality control.
•
Thoriated 2% (Red Band) Still considered the best for DC,
works ok for AC, but has been banned in many markets outside
the US due to a small radiation risk posed as an alpha emitter.
Do not use the following types of Tungsten.
•
Pure Tungsten (Green Band). This will create arc instability.
The tungsten will not stand up well to the more intense arc
created by an inverter welder.
•
Zirconiated Tungsten (White Band). This was created as an
alternative for Pure Tungsten for Transformer welders. Similar
issues welding issues are presented as with Pure Tungsten.
Getting Started
Purchasing Tungsten can be difficult. Local suppliers tend to put a
premium price on Tungsten, and may be three times an online price
direct from a distributor. In many areas, the choice of tungsten may
be limited. However, many local welding suppliers are stepping up
and offering competitive prices and range of selection, so don't rule
them out until you have checked. Also, there are some companies
that may send you free samples to test, so be sure to investigate their
product, and give them a chance as well.
GRIND THE TUNGSTEN CORRECTLY.
An improperly ground tungsten is a cause of many issues with arc
stability, arc directability, and penetration. A bench grinder and a fine
stone dedicated only for tungsten sharpening is all you need to put a
point on the Tungsten. This is the age old standard. This does take
practice to master. However, there are hand held special grinders that
feature diamond stones with guided slots, designed to hold the tung-
sten at the proper angles. A chemical sharpener is available and is
relatively inexpensive, and does an excellent job in seconds. An
added bonus of it is that it can be done without getting up from the
bench top without removing the tungsten from the cup. The tung-
sten should be hot before attempting as this activates the chemical.
Wear safety glasses and leather gloves while grinding tungsten or
serious injury may occur. On occasion tungsten may split or shatter.
Do not breathe or inhale tungsten dust. Do not use angle grinders!
•
Grip the Tungsten firmly. Grind with the tungsten secured.
•
Grind the Tungsten perpendicular to the wheel face. Allow tung-
sten to grind slowly without much pressure.
•
Rotate the Tungsten quickly as it is being ground to keep the
point even and symmetrical.
•
Do not grind the Tungsten parallel to wheel face or an unstable
arc will result.
22
WARNING!
!
How Do I Grind My Tungsten?
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