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
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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]