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I saved this and take absolutely no credit for any of it. T-bone is the man. Chuck J (Edited for content 01/25/04) Please update your file. Vertical up welding is fairly easy to do once you get the hang of it. Electrode angle pays a very important roll, about 5* to 10* down from horizontal, 0* works best sometimes, and you need your head below the rod to see the weld puddle with a close arc length and a slightly faster travel speed. Vertical down welds are allowed by AWS code and are limited to 2" in length on fillet welds but most welds fail when ran vertical down as it's very easy to trap slag with in the molten puddle. I only recommend very experienced welders use vertical down. Learn vertical up first! Now most welders watch the "slag" in the molten puddle and not the molten puddle it's self and that causes the molten puddle to fall or the weld puddle will slump before the welder moves the rod upward. Thats why we teach you to weld flat first so you can recognize the weld puddle from the slag. If you can see the difference in the weld puddle and the slag, then do not let the slag take your attention away from the molten puddle in the vertical position like it does to most welders. A vertical weave bead is made by starting a weld puddle then moving horizontal, 8 rod diameters max, then pause slightly to deposit more weld, move up 1/2 rod diameter, then back to the starting point. The horizontal move should be fairly fast so if the weld slumps in the center then your moving too slow. If the ends are under cut then your not pausing long enough at the corners. Take a scratch awl making two vertical lines will help you keep the weld straight and uniform width. The 8 times the rod diameter maximum is so the slag does not cool before you return to deposit more metal thus entrapping slag with-in the molten puddle. Use your arc length and travel speed to adjust for different welding positions. There is no need to adjust amps from flat welding to overhead welding to vertical welding. This is very important too learn for when welding in a 6G position. A 6G position is a pipe fixed at 45*. Which has more heat displaced content; 1) a long arc length, 2) a short arc length ?
A long arc length as the heat is spread over a wider area. This is why a short arc length is much easier to control the molten puddle. My method of teaching is to have the welder try to move too fast, too slow, long arc length, short arc length, rod angle at 45*, at 5*, too many amps, too low of amps, etc: and pay close attention to the changes each makes in the weld. I reverse teach, "what makes a bad weld". If you know what causes a bad weld then you will know how to correct it when you make that mistake. This is also where your plastic welding lens will fail you the most. You now have two weld puddles due to the distortion of the plastic lens. Which one is the true weld puddle? Use only a all glass lens. T_Bone
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