This is the reason for my post, a quote from a certain long-time fabber:
"It's called "stitch" welding, and it is exactly that. A series of tack welds. However, it is vital that you do it correctly, for strength. The reason that stitch welding is popular is it can actually be stronger then one continuous weld.
The idea is to crank up the amperage to where you almost get burn-through. If you were to have the heat set this hot, and try to run a continuous bead, you would be cutting holes in the metal. By stitch welding, the heat gets hot enough to penerate into the metal, to almost burn-through, but then you stop for a split second to let it cool, then move on to the next stitch.
The penetration is evident by looking at the back side of the welded area. It looks almost the same as the top! I do stitch welding in areas that I'm welding two different thicknesses of steel together, and want great penetration, plus, the added bonus is it looks trick!
It takes a lot of practice and playing with your machine, and it changes with material thickness too. Some of the high-dollar M.I.G. welders have a stitch option, which is trick, cause the machine times the shut-off for you (adjustable), and makes the off-time consistent, with-out shuting off the gas flow. It's just like cheating!
But until you and I can afford the high-dollar machines, we must get good at the technique.
One last thing, with your 150 machine it will work, but only for the thinner metals (1/8" or thinner). I made the parts you see in the pictures out of a combo of 1/4" and 3/16" and I had my machine set at about 80%, and my M.I.G. is a 230 amp unit. Just play around with some some scraps and have fun.
Keep on Jeepin'."
so, does anybody use their stitch timer like this guy is alluding to?