For vertical welds get some fast-freeze rods. 6010 for DC, 6011 for
AC. Rod perpendicular to work. Hold a short arc. I as taught bottom
to top. Tip motion is critical. You must keep the rod moving or the
puddle slumps to the bottom. Two techniques, up and down or back and
forth. Movement should be about the width of the puddle. The idea is
to get a puddle started then move over the edge of the puddle to to
promote penetration while allowing the back edge to freeze. Then
returning to the center, briefly, to fill. Then back to the edge.
Keep a close watch on the puddle and not the arc to assure that the
puddle is not getting to liquid or slumpy. When the puddle gets to
hot so that it wants to slump it's best to break the arc till the
metal cools before continuing. Don't hang around trying to get the
puddle to look right. It'll slump on you in a hot minute. Keep the
weld progressing at all times. Break the arc 1/2 inch from the edge
of the metal to let the metal cool before attempting to to finish near
an edge.

As to galvanized pipe. We keep a jug of muratic acid for that purpose.
Soak the end to be welded in acid for 1/2 hour to remove coating.
Works like a charm. Grinding just tends to smear it. Don't breath
the zinc fumes from welding. it will give you a condition called
'welders flu'. Cold sweats, the shakes. It passes. Drinking milk
helps to flush the zinc out of your system.

Funny thing is I'd welded several quick and dirty projects using
zinc'd pipe without any problems. Then, one day, I was cutting some
plate and had put some sheet tin down to protect the concrete.
Didn''t realize till after I was done how bad an idea it was. The tin
had melted and there was white flakes everywhere. That night I had
the worst case of the shakes, for about two hours, couldn't lay down,
just paced about the dark house.

starbolin