Vertical Welding with 7018
I work as a welding instructor and have been a welder for a few years. I
am by no means the authority on all things welding but below are some ideas I
have related to welding vertical. This is in the context of learning to weld
with a 1/8" 7018.
b) Spreading the heat around helps it cool faster , slight manipulation helps even as little as 1/16" off center on a 3/16" fillet weld with 1/8" 7018.
c) Low amperage may help you be able to get a good looking bead but should be used carefully. Making a 3/16" fillet weld at 85 amps with a 1/8" 7018 may be fine for developing hand eye coordination on thin material but if you change the base metal thickness or try welding in another position you will have trouble.
d) Manipulating the electrode more rapidly will tighten up the ripples. The pause still happens on the sides but it may be un noticable to the eye. I allow my students to lightly hold part of the electrode holder while I weld. This has helped some instantly understand the concept. Other it was no help.
e) Maintain a short arc. Not so short you disturb the puddle but right up to it. When I manipulate the electrode to the side I can feel the plate edges on a tee joint. Having a long arc will heat up the area you are welding more rapidly . The voltage increases if the arc length increases. If the voltage increased so does the heat input.
f) Watch the trailing edge of the puddle. Use your travel speed and manipulation to keep it constant. Good clean lenses, proper position, and experience watching the puddle in other positions will help.
g) Not all joints weld the same. A Tee joint of 3/16" material can handle more heat without sagging than a butt joint or pad weld on the same thickness. Also as the heat builds up from previous beads, undercut and poor bead contour may be a bigger problem. 1/4" is more forgiving than 3/16".
h) The placement of your practice pieces in a booth can greatly affect your ability to control the electrode when 1st learning. Get in a position with as few unsupported joints between you and the arc as possible. With the proper electrode placement and resting people can burn an entire 14" 7018 and never pick up their wrist from its resting place. If you cannot be comfortable while welding the whole joint, start a little uncomfortable and weld to where it is comfortable. Be aware the rod gets shorter.
i) When practicing and the situation allows, get enough pieces to allow others to cool of slightly . Try this experiment. Weld a tee joint single pass vertical with 1/8" 7018 on some 3/16" flat bar. Then immediately weld the other side of it . Look at both welds and see if the 2nd looks different or required a different technique. Then do the same on a 2nd assembly but let it cool between sides to where you can touch it. See if both sides weld the same.