Need some advice on Tig welds

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HiI know I should have some pictures to help here but I will try to get some later.I'm looking for advice on my Tig welding on mild steel. Most of my welds seem to come out with a dull matt grey finish. The shape of the beads and everything else looks OK it's just the matt grey finish which doesn;t seem to match up with the nice shiny beads I see on here.Anyone have any input as to what I might be doing wrong? Is it too much heat or too little gas?I'm using an inverter, 2% ceriated tungstens sharpened to a point, not running pulse, and using 1.6mm ER70S filler material.
Reply:With mild steel, you really don't need to have a shiny finish.  Are you grinding the mill scale off and cleaning the steel before you weld?  That might help you toward your goal of shiny beads.
Reply:I've been taking a TIG class since August and I also hoped for a bright stainless type finish. Well, now I know better; they're almost all a dull matt gray finish until after the powered wire brush. Then they shine like chrome.  We're using hot rolled mild steel. The cold rolled stuff may be different and at least you don't have to clean off the mill scale on CR. Some guys in a shop environment will only use CR for TIG, just to save the hastle of cleaning off the mill scale.9-11-2001......We Will Never ForgetRetired desk jockey. Hobby weldor with a little training. Craftsman O/A---Flat, Vert, Ovhd, Horz. Miller Syncrowave 250
Reply:As stated above, Make sure the steel is clean. Tig is not a process that allows for dirty metal.  As far as the color of the welds mild steel tig beads will be a gray color.  Stainless and aluminum will be bright and shiny.I'm a Lover, Fighter, Wild horse Rider, and a pretty good welding man......
Reply:tig welds on mild steel can gleam shinny just like stainless. here is the short answer, cooler the weld is when it is exposed to oxygen the brighter the color it will be be. now that doesn't mean that anything is wrong with the welds you have been doing. if you just really want them shinny try pushing more argon or using a bigger cup
Reply:Thanks for the replies folks. Much appreciated.I have been using both hot rolled and colled rolled.Good to hear then that the dull grey is OK.
Reply:Hmm.  I must have been doing it wrong all these years, since mine came out shiny, on plate, tube, or otherwise.  Most common reason I see for turning mild steel grey is excessive heat input, followed by surface contamination, i.e mill scale, grinding dust, etc.
Reply:as quasi says you need a bit lower temp. it seems paradoxically that comes with a shorter (more focused/hotter) arc - more intense- and going a bit quicker...it just seems to me...if i crawl along the beads are very dull..