why cant I mig worth a flip?

admin

Hi this is my first post, although I have been lurking latlely. I can stick weld fine with my miller ac/ac with a wide variety of rods. I have even ran a couple of nice welds with my neighbors tig outfit, and I will occasionally run a little with o/a. But I cannot seem to run a decent bead with my mig machine(century 125) there is nothing wrong with the machine as I have the same problems with all migs. My bead looks ropey and thin. Not enough penetration.I am only interested in flux core, and I understand the limitations of these small migs. Also I have have noticed that this machine automatically turns the wire speed faster when changing to a higher tap, Is that normal. The better beads seem to be on settings 2 voltage(1-4), and wire speed 2(1-10) this is with .30 flux polarity is correct. wire speeds faster than 5 seem useless as the speed seems to outrun the heat of the puddle. Any suggestions would be appreciated.
Reply:Is  your Century gas ready? I have the Century GS 135 and I never could run what I would say was decent flux-core welds with it. After I first got it I switched right away to gas and it did pretty good for quite awhile then it went to acting up when mig welding. I had it in a shop once for repairs where they replaced the circuit board but it never did ever weld again as good as it had prior to the problem that it had. I feel like the circuit board it got was not a good one or else it has other problems besides the circuit board. I have used a smaller mig welder than my Century that did a lot better with flux core. Honustly with either flux core or with mig welding. A friend brought over a Campbell Hausfield and welded up things I was having no luck with on the Century Welder. I let him try my Century and he didn't have anymore luck with it than I did. I tried his Campbell and could weld with it, so I am sure the Century has a problem.