Hi RadiationBurn,

There are two ways to perform a vertical weld. Either start at the bottom and work up (vertical up), or start at the top and work down (vertical down), which is also called downhand or a wash pass. If welded properly, vertical up is just as strong as a flat weld of equivalent size, while vertical down is basically a cosmetic weld. Compared to a vertical up weld, a downhand has very little strength. Of course, it's easier to do and looks nice, but don't be fooled by its appearance. Vertical down is normally used to weld thin materials because the arc penetrates less because of the faster travel speed. The pre-weld setup is critical for making high quality welds. Since you are fighting gravity, the voltage and amperage is normally reduced 10-15% from the settings for the same weld in the flat position, and remember that the current used for welding vertical up is higher than the current used for welding vertical down. For vertical up welding, a triangular weave or a slight weaving motion is normally used, while welding a shelf at the bottom of the joint and adding layer upon layer. In other words, don't get too creative with your movement. I've seen some guys learning to weld vertical up and they look like they're trying to write a letter to Santa Claus. Don’t whip or take the electrode out of the molten pool. Point the electrode slightly upward so that arc force helps control the puddle. The travel angle of the gun is a 5 to 15 degree drop from the perpendicular position. Travel slow enough to maintain the shelf without spilling, or bird crapping, as you called it. The best thing to do is practice on some scrap pieces, and don't be discouraged if it seems like all the weld metal falls down and looks bad. It takes a while to figure out vertical up welding, but it can be done if you have the patience.