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On the job or in the garage,
every welder needs protection to prevent eye
damage.
As a general rule, spending
more on a welding helmet will increase
comfort, improve your welding ability,
result in higher quality welds and ensure
your safety.
Unfortunately, selecting a
helmet can be confusing if you're not
familiar with the latest auto-darkening lens
technology and national safety standards.
This article will help you
sort through the clutter and point out the
most important things to consider before
investing in this important piece of safety
gear, while showcasing some of the
industry's top trends and designs.
Auto-Darkening or Standard
Glass Lens
The first question to ask
when buying a welding helmet is which type
of lens is right for you.
Standard — or passive —
welding helmets are as common today as they
were 50 years ago.
Although now made of molded
plastics instead of thick leather, these
helmets provide basic protection and budget
prices, from $20 to $30.
The viewing lens — or filter
— is a special piece of dark tinted glass,
most often with a #10 shade and ultraviolet
(UV) and infrared (IR) coatings.
When the welder is ready to
begin welding, a quick nod or snap of the
neck flips the helmet down before striking
an arc. When finished, the welder reaches to
pivot the helmet up and away from his face
to view the work piece and to reposition for
the next weld.
Although inexpensive,
standard helmets have several disadvantages:
It is difficult to keep the
gun/torch in the correct position to begin
welding after lowering the helmet in place,
especially for beginners.
When welding in restricted
spaces, such as under cars or trailers,
there isn't enough room to flip a helmet up
and down.
The repetitive task of
flipping up and down causes neck discomfort
after a day of welding.
And, finally, lifting and
lowering a helmet is inefficient especially
while doing a lot of tack welding.
Auto-darkening welding
helmets resolve all of these problems.
Instead of a standard piece
of tinted glass, helmets with auto-darkening
filters have an electronic filter lens and
often are equipped with adjustable features
to make welding easy. These features are
discussed below.
The auto-darkening filter
lens, or ADF, is a special liquid crystal
display (LCD) that is similar in design to
the technology used to display numbers on a
digital alarm clock.
Most filter cartridges are
powered by a combination of battery and
solar power.
Several light sensors are
mounted near the lens to detect the welding
arc. When the lens is not activated, an
auto-darkening LCD filter usually has a #3
or #4 shade, which is relatively easy to see
through, similar to sunglasses.
This makes arc starts easier
because the welder can see the position of
his MIG gun, TIG torch or stick electrode
relative to the material he is welding.
Once an arc is initiated,
sensors on the helmet darken the lens to a
shade #9 to #13, depending on the settings,
hundreds of times faster than you can blink
an eye.
Because the filter has UV and
IR coatings applied to it, eyes are
protected from harmful rays regardless of
active/inactive shade setting.
Best of all, the helmet stays
down before, during and after the job is
being done.
Auto-darkening welding
helmets enable you to setup a welding joint
with the hood in position.
No more head snaps to lower
the helmet.
No more sloppy starts because
the torch moved.
Fixed or Variable Shade
If most of your welding
involves one type of material, such as
steel, of the same thickness, using the same
welding process, such as stick, at the same
amperage, then a fixed shade #10 lens is all
you'll ever need.
Standard glass lens helmets
obviously are fixed shade, and the least
expensive auto-darkening helmets also are
available in fixed shade.
However, most people weld
different materials, such as mild steel,
stainless steels, and aluminum, and with
different thicknesses that require the use
of different welding processes, such as
stick, MIG and TIG, for specific jobs. That
means the welding amperage can vary from 40
amps to more than 200 amps.
With that variance comes
varying degrees of brightness in the arc.
To properly protect your eyes
and get the best view of the weld puddle,
you need to have an adjustable or variable
shade lens.
These adjustments are found
either inside the helmet on the lens, or
outside on the side of the helmet. Most
variable shade lenses adjust from shade #9
through #12 or #13. It may be unlikely you
need the shade #13 setting as seen on the
suggestion chart below unless you weld at
extremely high amperage or have very
sensitive eyes.
Switching Speed (Lens
Reaction Time)
As you shop for an
auto-darkening helmet, you'll notice that
most manufacturers advertise the lens
switching speed.
This number tells how fast
the lens will switch from its natural light
state — usually shade #3 or #4 — to the
darkened shade when welding begins.
The quicker a welder's eyes
are shaded from the high-intensity light,
the better. Too slow a reaction time will
cause eye discomfort that feels like a dry
scratchy sensation sometimes referred to as
arc flash.
Entry-level lenses often are
rated at 1/3,600 of a second switching
speed. Intermediate and professional level
helmets switch at speeds as high as 1/16,000
of a second or faster. Some manufactures
advertise this rating in a decimal; to
compare those ratings, divide 1 into 3,600
for the decimal equivalent. Generally
speaking, the faster the switching speed,
the more expensive the helmet and lens.
So why pay more for a faster
lens? In a word: Comfort.
If you spend all day welding
with a lens rated at 1/3,600, which I
considered a slower reaction time, your eyes
will feel fatigued by the end of the day and
could have the dry, scratchy symptoms of arc
flash as mentioned earlier.
With faster switching speeds,
these effects are eliminated.
Solar Power and Battery Life
Some auto-darkening helmets
are designed with an internal,
non-replaceable battery and solar assist
panel. These helmets often require a
charging period in direct sunlight prior to
first use, and a similar charging period if
they are stored for an extended time, which
can be a real bummer when you want to weld
right away.
The disadvantage with this
type is once the battery wears out the lens
doesn't work.
A better investment is a
helmet powered by a replaceable battery and
solar assist panel that enables you to start
welding right away.
Choose a lens with an AAA
battery for economical replacement cost and
availability everywhere. Choose a lithium
battery model for extended battery life.
However, lithium batteries have higher
replacement costs and are slightly more
limited in availability. Typical AAA battery
life is approximately 2,000 hr for MIG
welding.
Adjustable Sensitivity and
Delay Controls
Both intermediate and
professional level auto-darkening helmets
usually provide the ability to adjust how
much brightness will trigger the lens to
darken.
Sensitivity control is useful
when welding at low amperages — especially
with a process such as TIG, when the arc
isn't as bright as it is with other welding
processes.
A delay control is another
useful feature.
This control enables you to
set how long the lens stays dark after the
welding arc stops.
When tack welding on a large
project, a short delay helps to get the job
done faster as you reposition for the next
weld. A longer delay time is helpful when
welding at very high amperages to prevent
you from looking at the weld zone after the
arc extinguishes.
Depending on the manufacturer
and price, these features often are
controlled by toggle switches for high/low
sensitivity and fast/slow delay.
Professional level helmets typically will
use infinite range dials to deliver greater
adjustment capability. Entry-level
auto-darkening helmets typically do not have
either of these features.
Helmet Weight
A lighter weight helmet
minimizes strain on the user's neck and
reduces fatigue while increasing comfort.
You will notice a big
difference between a helmet that weighs 1 lb
versus one that weighs 2 lb.
While 1 lb might not seem
like much for a few short welds, it can
become a great weight when working on an
all-day project.
Think of the old trick of
holding a book out at arm's length. It's
easy for the first few seconds, but it seems
to weigh a ton after a minute or two.
The same goes for a heavy
helmet vs. a lighter option: sooner or
later, greater weight will cause discomfort.
National Safety Standards
The most recent safety
standard for welding helmets is ANSI Z87.1 –
2003. This standard requires helmet and
auto-darkening lens manufacturers to
validate their advertised specifications
such as switching speeds, darkness shade
settings, and other specs, through
independent laboratory tests to advertise
compliance.
These rigorous tests require
the helmet and lens to survive high velocity
impact tests from flying objects, provide
100 percent ultraviolet and infrared
filtering regardless of shade setting, and
meet advertised switching speeds and
darkness shades in extreme temperatures.
The auto-darkening lens must
engage and perform at temperatures as low as
23 degrees F and as high as 131 degrees F to
ensure consistent protection. If you live in
Texas or Minnesota, that's real world
welding.
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