MIG weld bead questions

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Hi,I just started MIG welding recently, and after much reading of this and the Hobart board, am not totally satisfied with the appearance of the weld bead.I am using a MM175, ER70S6 wire, .030 dia and C25 shielding gas.  I have been practicing on .050 thick cold rolled steel that I had laying around - so the metal is pretty clean and free of scale to start.  I have tried wire brushing, fine sanding, and degreasing before welding.  So I THINK the prep is ok.  Most of the practice welds I have attempted are normal flat butt welds.My concern is that the welds do not appear "silvery" and shiny like some of the posted pictures I have seen on both this board as well as on the hobart board.  They do not look rough and they are not porous - just not silvery in color like many of the examples posted.  Mine are more of a "gun-metal gray" in appearance.   Penetration appears adequate with my settings, with the weld just coming through the backside of the joint.I have checked all of the gas lines for leaks - there is certainly no leak between the gas flow regulator and the welder solenoid valve.  It holds pressure for a week.  The gun-cable assembly is also in good condition as it is brand new, inserted and clamped properly and all connections tight.What could be the problem?  Too high a voltage setting?  Or is there something else I am totally missing?Thanks for any and all help!Mike
Reply:Hmmmmn........you are probably just fine. I will have to look at some of my beads to compare. I use CO2.
Reply:Mike,What part of So Cal are you in?  I'm in San Diego.Ned
Reply:I'm up in Bakersfield.
Reply:what are you cleaning them with after you weld??, i use a wire wheel in a drillStangnetShop Full Of Stuff. Joey
Reply:B2...I think you may find that it has to do with the brand of wire.I noticed that when I recently had to put a new spool in my machine.  Funny thing though...I had a spool of some "off-Brand" in the machine...didn't even have a name on it.   I bought it from "Tri-Tech", and I assume it's their "House-Brand".It gave beautifully shiny welds.   When that ran out, I put a roll of Lincoln wire in, and the beads are, as you say: "Gunmetal"I don't think there's anything wrong with the wire though.....it still welds nice.   I think it's just a cosmetic factor, and nothing to worry about.I'll be the LAST one to let you down !
Reply:Thanks for all the help - I guess it is probably ok; I'll just keep on practicing.  By the way, I'm in Torrance.Mike
Reply:Oh, and by the way, I have not done any post-weld cleaning.  There doesn't seem like there is much to clean, it is just that the welds do not come out bright silver in color.Thanks again for all the responses!
Reply:I'll second Marcopolo on the cosmetic issue.I use 100% CO2, and generic wire from whomever's cheaper on eBay at the time.  The quality of the weld is fine, and the "gun-metal" color doesn't bother me at all.
Reply:I'm thinking the color and appearance of the bead is probably a result of the bead being a composition of the parent metal of the weldment and the wire.  Unless you are absolutely dead on with the composition of all pieces in the weld you are basicly creating a new steel in the weld itself.Normally, very little attention is paid to weld color, as long as the weld is good and holds.Appreciation Gains You Recognition-
Reply:Are you running the proper gas pressure. That can realy mess with your welds and try runnign argon gas instead of co2 it makes a cooler weld. I have a syetemaic (Centry made) 175. It is running .35 wire size right now with 20-25 lbs of argon line pressure. For the thicker metal then .30 with bout the same pressure for autobodie work.Thats my 2 cents.Hi-Jack