I tried some 7018AC and 6011 electrodes in welding class today. I normally
use 6013 (Lincoln Fleetweld 37) supplied by the school. It works very well
but I wanted to try something different. I was very surprised to find the
7018AC easy to use. The arc was smooth and the bead looked beautiful
(similar in appearance to 6013). The slag was very easy to chip off--easier
than 6013, especially on a T-joint. But the 6011 was a different story.
First, it made a very loud buzzing noise (kind of like AC TIG aluminum
welding). The bead penetrated the metal well, but was unsmooth in
appearance. The main problem was removing the slag. I had to literally
pound the weld with all my might. And even then some slag remained on the
surface. I'm not talking about slag trapped in a hole, but rather slag on
the surface of the weld. I was using a Lincoln Idealarc 250 AC. 3/32"
Lincoln Fleetweld 180 6011 rod from a new, sealed box. 1/4" mild steel.
Flat weld. Lincoln recommended 70 amps--which I tried--but I also tried
from 25 to 150 amps. Same problem. The class only has one AC/DC stick
welder--the rest are AC only. I did most of the welds using AC but I tried
the DC welder when it became available. Both straight and reverse polarity.
There was very little difference. I can't figure out what I did wrong. Any
18 years ago