The Fabricator - August 2009

CFIGURE 7 When welding from left to right, maintain a 0- to 15-degree angle tilted toward the direction of travel. This is known as the drag, or backhand, technique.

Angle of Travel. Stick welding in flat, horizontal, and overhead positions uses a drag, or backhand, welding technique (see Figure 7). Hold the electrode perpendicular to the joint, and then tilt the top 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 electrode 0 to 15 degrees away from the direction of travel.

Manipulation of Electrode. Each welder manipulates the electrode a little differently than the next. Develop your own style by observing others, practicing, and noting which techniques produce the best results.

Note that on material 1⁄ 4 in. and thinner, weaving the electrode is typically not necessary because the bead will be wider than necessary. In many instances, a straight bead is all that’s needed.

To create a wider bead on thicker material, manipulate the electrode from side to side, creating a continuous series of partially overlapping circles in a Z, semicircle, or stutter-step pattern (see Figure 8). Limit side-to-side motion to 2. 5 times the diameter of the electrode CFIGURE 8 A semicircular motion is used to create a wider bead with a stacked dimes appearance. For thinner welds, a straight-line bead may be sufficient.

core. To cover a wider area, make mul-
tiple passes or use stringer beads.
When welding vertical-up, if you
focus on welding the sides of the joint,
the middle will take care of itself. Move
across the middle of the joint slowly
enough so that the weld puddle can
catch up, and pause slightly at the sides
to ensure solid tie-in to the side wall. If
your weld looks like fish scales, you
moved forward too quickly and didn’t
hold long enough on the sides.
Speed of Travel. Your travel speed
should allow you to keep the arc in the
leading one-third of the weld pool.

Traveling too slowly produces a wide, convex bead with shallow penetration and the possibility of cold-lap-ping, in which the weld appears to be simply sitting on the surface of the material (see Figure 9).

Excessively fast travel speed also decreases penetration, creates a narrower or highly crowned bead, and possibly underfills or undercuts. Note toward the end of the bead in Figure 10 how the bead appears inconsistent, as if the puddle were trying to keep up.

These tips, along with practice and patience, will get you headed in the right direction. ■

Brad Hemmert and Amanda D’Arcy are welding engineers, Miller Electric Mfg. Co., 1635 W. Spencer St., P.O. Box 1079, Appleton, WI 54912, 800-426-4553, www. millerwelds.com.

CFIGURE 9 Travel speed that is too slow will create a bead that has too much weld deposit, which can result in insufficient penetration in those areas. Traveling too slowly also can focus the heat into the puddle and not into the base material.

CFIGURE 10 Traveling too fast will create a thin/undersized bead that will have more of a V-shaped ripple effect in the puddle rather than a nice U-shape, or a stacked dimes, effect.

Visit www.thefabricator.com and type these article titles in the search box: A “Vertical SMAW: It’s a stick up; 5 tips to get it right when it’s needed most“ A “Field welding repair: Key steps and equipment selection“ A “Stuck on SMAW? Easy answers to 8 common electrode questions“ Want more information?

The FABRICATOR® | An FMA Publication August 2009 | www.thefabricator.com

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