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*Tip of the Week*
**
*Basic Tips to Improve Stick Welding (Miller Welding)*
**
Shellfish can make you a better welder. Simply think about CLAMS: Current
setting, Length of arc, Angle of electrode, Manipulation of the electrode
and Speed of travel. If you're just learning the Stick process, technically
called Shielded Metal Arc Welding, remembering these five points will
improve your welding technique.


*Remember CLAMS*
Now that you're ready to weld, remember CLAMS. Bringing all these points
together in one moment of welding may seem like a lot to think about, but it
becomes second nature with practice. And don't get discouraged! Stick
welding got its name not because the electrode looks like a stick, but
because EVERYONE sticks the rod to the workpiece when learning how to weld.

*Current setting:* The correct current, or amperage, setting primarily
depends on the diameter and type of electrode selected. For example, a 1/8
in. 6010 rod runs well from 75 to 125 amps, while a 5/32 in. 7018 rod welds
at currents up to 220 amps. The side of the electrode box usually indicates
operating ranges. Select an amperage based on the material's thickness,
welding position (about 15 percent less heat for overhead work compared to a
flat weld) and observation of the finished weld. Most new welding machines
have a permanent label that recommends amperage settings for a variety of
electrodes and material thicknesses
.

*Length of arc:* The correct arc length varies with each electrode and
application. As a good starting point, arc length should not exceed the
diameter of the metal portion (core) of the electrode. Holding the electrode
too closely decreases welding voltage. This creates an erratic arc that may
extinguish itself or cause the rod to freeze, as well as produces a weld
bead with a high crown. Excessively long arcs (too much voltage) produce
spatter, low deposition rates, undercuts and maybe porosity.
Many beginners weld with too long of an arc, so they produce rough beads
with lots of spatter. A little practice will show you that a tight,
controlled arc length improves bead appearance, creates a narrower bead and
minimizes spatter.

*Angle of travel:* Stick welding in the flat, horizontal and overhead
position uses a "drag" or "backhand" welding technique. Hold the rod
perpendicular to the joint and tilt the top of the electrode in the
direction of travel approximately 5 to 15 degrees. For welding vertical up,
use a "push" or "forehand" technique and tilt the top of the rod 15 degrees
away from the direction of travel.


*Manipulation:* Each welder manipulates or weaves the electrode in a unique
style. Develop your own style by observing others, practicing and creating a
method that produces good results for you. Note that on material 1/4 in. and
thinner, weaving the rod typically creates a bead that is wider than
necessary. In many instances, plain, straight-ahead travel works fine.

To create a wider bead on thicker material, manipulate the electrode from
side to side creating a continuous series of partially overlapping circles,
or in a "Z," semi-circle or stutter-step pattern. Limit side-to-side motion
to 2-1/2 times the diameter of the electrode core. To cover a wider area,
make multiple passes or "stringer beads."
When welding vertical up, focus on welding the sides of the joint and the
middle will take care of itself. Pause slightly at the side to allow the far
side of the bead to cool, the weld puddle to catch up, and to ensure solid
"tie-in" to the sidewall. If your weld looks like fish scales, you moved
forward too quickly and didn't hold long enough on the sides.

*Speed of travel:* The proper travel speed produces a weld bead with the
desired contour (or "crown"), width and appearance. Adjust travel speed so
that the arc stays within the leading one-third of the weld pool. Slow
travel speeds produce a wide, convex bead with shallow penetration.
Excessively high travel speeds also decrease penetration, create a narrower
and/or highly crowned bead, and possibly undercuts.


A few last words of advice. Always remember that you need a good view of the
weld puddle. Otherwise, you can't ensure you're welding in the joint,
keeping the arc on the leading edge of the puddle and using the right amount
of heat (you can actually see a puddle with too much heat roll out of the
joint). For the best view, keep your head off to the side and out of the
smoke so you can easily see the puddle.

Also remember that you learn through mistakes. There's no shame in grinding
out bad welds. In fact, professional welders create perfect welds by
recognizing imperfections, grinding them out and rewelding.


--
Von G. Peavy
South Region
Area Mechanics Teacher
Georgia Department of Education
Office of Agricultural Education
ABAC 34  2802 Moore Highway
Tifton, GA    31794
Phone: 229-386-3868
Fax: 229-391-6838
e-mail: [log in to unmask]