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| There are several good suggestions here, Getting a welding course outline and some pointers from an instructor would be a good idea.
E7018 is a good electrode 3/32" and 1/8" diameter are commonly used for all position pipe welding, in the vertical position the weld bead progression is uphill. (notice I did not say pipeline, they generally use E7010 or similar downhill electrodes)
It is much easier to learn to weld SMAW (stick electrodes) with a good DC welding power supply, electrode positive is the correct polarity for E7018. E7018 can be used with AC power as well, for pipe welding and heavy structural fabrication, DC is used.
First, a welding course might begin with welding parallel beads on flat plate, learning to set the machine, then welding overlapping beads on flat plate.
Next they might have you weld beads on a plate in the horizontal position, (plate standing on it's edge, weld a bead as if you are drawing the horizion line on a wall), then overlapping beads in the horizontal position, bottom bead first, second bead above the first, overlap covering 1/3 of the first bead, electrode angled up at a 45 degree angle.
Next they might have you weld beads vertical up (starting near the bottom of the plate and progressing to the top) on a plate, electrode angled up at a 45 degree angle, then overlapping beads in the vertical uphill progression, overlapping the beads 1/3 to nearly 1/2 over the last pass.
Next they might have you weld beads overhead on a plate, then overlapping beads on an overhead plate. The elecrtode angle should be nearly 90 degrees from the plate surface.
The welding course might progress to T-joint plates (fillet welds) in the flat (1F), horizontal (2F), vertical up (3F) and overhead positions (4F), then to groove welds in the flat (1G), horizontal (2G), vertical up (3G), overhead (4G) positions. After you become proficient as a plate welder, you may begin practicing pipe welding, in the horizontal, (2G) vertical up 5G or with the pipe axis on a 45 degree angle (6G) positions. For pipe welding, you may do groove welds with a backing ring on the inside of the pipe between the two pipes you are joining, or you may learn to weld a root pass with a gap between the (beveled) pipe ends. You may use E6010, generally in the uphill progression for the root pass, or you may use heli-arc with ER70S2 or ER70S6 filler metal for the root pass.
Just learning to weld plate in all positions is a good start. Much of what you learn in a SMAW (Shielded Metal Arc Welding) course is fundamental for use with other welding processes. GMAW (solid wire electrode) is used quite a bit in manufacturing, but it is somewhat limited for all-position welding. Gas shielded FCAW (flux core electrode) is used for much of the all position welding in heavy fabrication and shipyard work, it is not like the small self shielded FCAW electrodes used in a 110 Volt wirefeed machine.
SMAW Low hydrogen (E7018) and GTAW (heliarc) are craftsman's processes. GMAW is easier to learn, more production oriented, but more limited as to the positions it works well in. Pulsed GMAW or (gas shielded) (FCAW) flux core will get around some or most of the limits of the basic GMAW process.
After a while, you will get used to restarting E7018 electrodes, smack them a little bit, tap them on the concrete, bend the rod at a 90 degree angle right by the electrode holder so they don't slide when you give them a good tap. Also, learning is easier when you keep a clean cover plate and a clean filter plate (#9 or10) in your hood.
Edited by e81t1k2 3/4/2008 06:16
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Cant weld worth a crap
