Rich they were using solid wire with gas. My machine will run flux core but I don't use it. Actually I'd rather use my stick welder if the gas method won't work. There are time when the stick is best. Outside in the wind for example, I know flux core will work as well but I'd rather not have the time or expense in switching.
Flux does have it's place however, they all do.
The reason that I asked is because, in that particular case of pulling when using sloid wire, I disagree with their recommendation.
Now, I realize that the Miller guys should be at the top of the welding information food chain, but I have been welding for a living since 1974.
I've done nuclear and non-nuclear welding, every method of manual and semi-automatic welding that you can think of, and lots of it. I was a welding instructor for several years at a submarine manufacturer, and at a local college. I'm not trying to impress anyone here, I'm just trying to make a point that I've been well schooled, and based on my experiences, I disagree.
If I was welding two pieces of 16 ga. sheet metal together, at a seam, and I was pushing the gun, and continued to keep going without stopping, I would stand a good chance of eventually blowing through. The gun angle, when pushing, is continually pre-heating the surface ahead of you. Eventually the heat becomes so great, that if you don't stop, you'll blow through. This also means that you're getting great penetration.
So...you have to learn to push the gun, and know when to stop, before blowing through. This way, you get the good penetration, and a strong weld.
I use the "back step" method. This means that (after the pieces are all tacked up) I'll start at about 6 inches from the end of the seam, and weld those (last) 6 inches. Then, I'll start 6 inches behind that bead, and weld up to the start my first bead. Then start 6 inches behind the second bead, and weld up to the start of the second bead. continue in this manner until the weld is completed.
With this method, the heat never gets too great ahead of you. Usually, there's less warping, too.
I originally used the example of 16 ga. sheet metal. I chose that thickness to illustrate the possibility of blowing through. On thicker metal, the odds of blowing through are much less. The backstep method is still good to use on the thicker stuff, like .125, .187, or .250" thick material.
Getting back to the 16, or 18, or whatever thin gauge metal guys use for tub repairs, you actually could drag the solid wire, if you choose to do so. The reason I say this, is because, it doesn't take much to penetrate this thin stuff, and there is LESS of a chance of blowing through. I know it sounds contradictory to my opening example. I was just trying to create a picture of blowing through a piece of metal, and I figured that if you pictured something this thin, you'd get it.
I guess the bottom line is, we all have to experiment, and see what works for each of us, individually. This post is just what I've experienced.