lack-luster/grey welds?

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I'm in the middle of a piece work job for a local machine shop welding a thick bushing in the end of thin wall tubing, both are carbon steel. My machine is a Lincoln power mig 180c, running .035 e70s6, around 225 ipm and 160 v/a current. The finished weld on the current batch of tubes presents with a dull, grey color and some small distortion in the bead steps. Past practice, I have been able to adjust variables to produce a nice shinny weld. Oh yeah, I'm running 75/25 shield gas and using a variable speed, foot peddled positioning table. Anyone have tips?Miller TrailBlazer 251Miller HF-250-1Miller MaxStar 150 STLHyperTherm PowerMax 380 plasmaLincoln PowerMig 180Millermatic 252Miller Diversion 180
Reply:Sounds like to me to hot or to much wire speed just have to play with it and find the sweet spot..
Reply:Wagin,I'd recommend dropping back to a .030 wire in that machine."Grey" beads are often times a sign of too much heat.Syncro 250 DX Dynasty 200 DXMM 251 w/30A SG XMT 304 w/714 Feeder & Optima PulserHH187Dialarc 250 AC/DCHypertherm PM 1250Smith, Harris, Victor O/ASmith and Thermco Gas MixersAccess to a full fab shop with CNC Plasma, Water Jet, etc.
Reply:Thanks guys, now that you mention it, the last batch I ran at this speed I was running .030. thanks again.Miller TrailBlazer 251Miller HF-250-1Miller MaxStar 150 STLHyperTherm PowerMax 380 plasmaLincoln PowerMig 180Millermatic 252Miller Diversion 180