Shielding Problem?

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Hey Guys,Please take a look at these pictures.  Do I have a sheilding problem?  I am new to TIG welding so I don't know if the white/bluish haze on my beads is normal.  My setup is:Precision TIG 225100% Argon at ~15 CFM with 15 second Postflow17 series torch (came with welder)3/32" Red Tungsten (Freshly Ground)#7 Gas LensI ran these beads on 1/8" Mild Steel, cleaned with a flapwheel.  The top bead was done with ER70S-6 (1/16") filler and the bottom was ER70S-2 (1/16").  The welder was set at 130 Amps but I was using a pedal so I was probably running closer to 80 - 100 Amps.Obviously I still need a lot of practice keeping my bead width and dip spacing consistent, etc. but I am wondering if I also have a problem with my setup.  I have tried everything I can think of to try to get my welds to come out shiny like some that I see on this site.  I have tried from 10 - 25 CFM Argon flow, #4 - #8 Gas Lenses and "Normal" Cups", 1/8" - 1/2" Tungsten "Stick-out".  I make sure to keep my filler in the gas flow.  I make sure to clean the steel really well with my angle grinder and a flapwheel.  I am welding in my garage with the door closed and no fans on.  I have checked all gas hoses/connections for leaks using soapy water (I haven't checked connections internal to the welder).  After seeing CapnBondo's recent thread I am starting to suspect I may have gotten some bad Argon.  What do you think?  Is there anything else I should check?Thanks,Mickey Attached Images
Reply:The whitish stuff around the weld, can it be wiped off or does it have to be ground off..Yup
Reply:It has to be ground off.
Reply:Any ideas?  Is this what it looks like when you get a bad bottle of Argon?Thanks,Mickey
Reply:A leak in the system doesn't normally look like that, slightly dirty welds and a little porosity. What does the tungsten look like after welding? eroded, discoloured? Is there any 'spitting', smoke or sparks when welding- DC tig should be spark free and virtually silent. Was the steel coated? No need to have 15 secs of post flow, just a waste of gas. Been a while since i've done any welding with an aircooled torch but 8-10 secs should be more than enough time to protect the tungsten- all you need to worry about at the moment is enough to prevent the hot tungsten from discolouring
Reply:I haven't had any tungsten eroding and I haven't noticed any discoloration (although I haven't been looking for it).  It may turn slightly whiter or lighter grey.  No smoke or sparks and it is almost silent.  It really does seem to weld nicely (not that I have anything to compare to) but I just can't get it to come out shiny.  I don't think the steel was coated but I also ground it very clean.  Thanks for the advice on the postflow.  I will turn it down.  What color will the tungsten turn if I don't have enough shielding/postflow?Thanks,Mickey
Reply:Tungsten,... gold, greenish, blue followed by a manky grey if really oxidised.Mild steel is never going to be as shiney/brightly coloured as stainless, nothing wrong with grey. The 'colours' simply denote how hot the metal was when shielding was lost as the torch moved. Weld too hot, too slowly and the weld/surrounding area will be hotter when exposed to the atmosphere resulting in a larger coloured area/darker colours. Don't worry about any of that for now. Run beads on plate trying to keep them all a consistant size until you're comfortable then do some real joints.
Reply:If you're running a gas lens, I run my argon at 20, might give that a try....Regards, KevinI r 2 a perfessional
Reply:Guys, what is that whiteish residue?  Is it possible his filler rods are for oxy and not the ERS rods they should be? I know the 1/16" filler I got had no stampings on it so it's a matter of trusting my LWS.Is it possible he's putting too much heat into the weld? I'm new to all this too, but my Miller handbook seems to say 80 amps is more typical of what you'd weld 1/8" plate with. I undertand you're using a foot control, but I don't know how linear they are. Maybe set the welder to 80 or 90 amps and try it again?
Reply:Thanks for all of your help, everyone.  I played around with this quite a bit this weekend.kbnit - I tried turning up the gas (even as high as 25 CFM) but it didn't seem to make a difference although running around 18 CFM helped a lot with Aluminum.Turboguy - All of the filler I have has the ERS number stamped on the ends.  I tried each of the different fillers I had (1/16" ER70S-2, 3/32" ER70S-2, and 1/16" ER70S-6) and they all came out the same.  It is definitely possible that I am putting too much heat into it.  I set it based on the 1 amp per .001" rule of thumb.  I will try turning it down.Hotrodder - I don't seem to be getting any tungsten discoloration (I am keeping my eye out for that now).  I am definitely still in the practicing stage and not doing any real joints.  I just wanted to make sure I don't have a problem with my setup that would make it harder to learn with.This weekend I also tried running some beads on some 1/8" 304L stainless using 1/16" 309L filler (Sorry, I didn't take any pictures).  When I ran some narrow beads they came out shiny and gold colored but when I turned up the amperage to get a little better penetration the beads came out a dull grey color with the exception of the end of the bead where the postflow was.  I think it is what hotrodder said about the weld/surrounding area being too hot when the torch moves away and it is exposed to the atmosphere.  I tried running really slow with less heat but I didn't get very good penetration and it really didn't help much with the dull grey coloration.  I also tried going as fast as I could with more heat but that came out darker grey (I'm guessing because I was moving the argon away faster).  Does anyone have any tips for heat settings and travel speed?I have heard of using a copper "backing block" to help pull heat out quicker.  Do you think that would help?  Right now I place my work right on my welding table top which is made out of .065" wall rectangle tube so that probably isn't pulling out much heat.  Would an Aluminum backing block work well enough or would it be likely to melt?Thanks again for all of your help,Mickey
Reply:Originally Posted by moswald80I have heard of using a copper "backing block" to help pull heat out quicker.  Do you think that would help? Would an Aluminum backing block work well enough or would it be likely to melt?
Reply:Depends on what you're doing as to what backing bar you use.Most code/specification welding requires that the backing bar be the same material as the material being welded.  That's so if you burn through like turboguy said, you won't contaminate the weld.For general welding, a healthy piece of aluminum works well as a backing bar for most materials, particularly since it doesn't fuse to most steels. I use a 2 foot diameter, 1" thick aluminum "lazy susan" for most of the welding that I do tabletop.  Automated seam welders use copper or beryllium copper backing bars.  Just be aware that if your weld is dropping through, and contacts the backing plate, the higher rate of cooling will cause shrinkage ripples on the underbead of the weld, and while not detrimental, they're hardly cosmetically pleasing.And, yes, turbo, if you use aluminum to back aluminum, you could very well end up with one piece.....Regards, KevinI r 2 a perfessional
Reply:What are you using to mark the lines on the plate? It looks to me as if whatever you are using is being sucked into the molten pool and causing a bit of contamination....Why are you marking the plate to begin with?http://all-a-cart.comWelding Cart Kits and accessories
Reply:I just scratched the straight lines to help me make straight(ish) beads.
Reply:http://www.millerwelds.com/education/TIGhandbook/There is a Chart for setting up for  MS, SS and ALCan't recall which chapter but a good read anyway.Ed Conleyhttp://www.screamingbroccoli.com/MM252MM211 (Sold)Passport Plus & Spool gunLincoln SP135 Plus- (Gone to a good home)Klutch 120v Plasma cutterSO 2020 benderBeer in the fridge