SS weld bead color question

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Greetings.I am welding several handrail parts. They are assembled fron 304 SS 2X2 tube 1/8th wall. The top cap is 304 SS 7 gauge plate. I used 3/32 2% tungsten, 1/16 in. 308 rod, 20cfm argon, The welder is an older Airco beastie! Attached is a photo showing the current settings. I adjusted the arc via a pedal to get a good puddle probable mid to upper range of pedal travel. The welds have a grayish color not the "cool" rainbow tints some are looking for. The HAZ and  bead both cleaned off nicely with our electro/chem cleaner as the photos show. I also included a photo of one of the handrails completed.My question is what might be the cause of the gray color?  Thanksmoose Attached ImagesTimmetalcraft by mooseSoutheast Michiganhttps://www.facebook.com/Metalcraftbymoose  Stupid Hurts!!
Reply:Not enough gas coverage causes the gray. Normally for big welds like this you need to gas cover the weld for quite some time to get good color (trailing gas cover). The only other option is make smaller welds so they cool faster.
Reply:Where is the amp adjustment set? I can't see the arrow on it, the coarse adjustment is set for up to 250amps in the middle I think. The welds in pics 2 and 3 and the right side of pic 4 look fine, just not really colorful. Usually its from using a smaller cup and the steel doesn't have time to cool enough before argon is no longer on it. You can fix this by using a bigger cup/ keeping a shorter stickout and reducing the total heat you put into the part.Airco Ac/Dc 300 HeliwelderMillerMatic 200 (stolen)Miller Maxstar 150STLMiller AEAD200LE (welding and generating power) Hobart MIG
Reply:What is the actual arc length that you are using?  It is likely too long in combination with too much heat. 1st on WeldingWeb to have a scrolling sig! HTP Invertig 400HTP Invertig 221HTP ProPulse 300HTP ProPulse 200 x2HTP ProPulse 220MTSHTP Inverarc 200TLP HTP Microcut 875SC
Reply:Originally Posted by SquirmyPugWhere is the amp adjustment set? I can't see the arrow on it, the coarse adjustment is set for up to 250amps in the middle I think. The welds in pics 2 and 3 and the right side of pic 4 look fine, just not really colorful. Usually its from using a smaller cup and the steel doesn't have time to cool enough before argon is no longer on it. You can fix this by using a bigger cup/ keeping a shorter stickout and reducing the total heat you put into the part.
Reply:Originally Posted by mooseThanks !Amp adjustment is set to 50%. The cap I believe is 1/2 or 5/8 openning using a gas lense. Becausethe welds are cleaned and then sanded to a smooth radius the color is not detrimental I ask more to learn and get better!  The bead width on the joint is about 3/16th to 1/4 inch. The joint fit had about a 1/16 step from the tube edge to the plate edge. VPT For my purposes the trailing cover would be bulky and more bother than the results warrant. I will keep that technique on file for other joints though!OscarThanks the arc length was about 1/4 inch...moose
Reply:the welds are just fine--------------------------------------------------------------www.becmotors.nlyup, I quit welding.. joined welder anonymous
Reply:The welds are likely just fine,  as Donoharm says,  but the excessive arc length is not helping the colors--if you shrink it down to 1/8" or less you can significantly decrease total power and thus heat into the piece while maintaining the proper amperage needed. 1st on WeldingWeb to have a scrolling sig! HTP Invertig 400HTP Invertig 221HTP ProPulse 300HTP ProPulse 200 x2HTP ProPulse 220MTSHTP Inverarc 200TLP HTP Microcut 875SC
Reply:Originally Posted by Donoharmthe welds are just fine
Reply:Looks like travel speed is a lil slow and when your at the end of the weld .linger there with the torch for a second or two with with your foot off the pedal. Allow the post flow to cool the end of the weld.  And keep its color rather then the weld look nice and the end is gray. Welding 1/8th in stainless you don't really want to be no more then 125 amps. And 3/32 filler is a good size rod to use. I like to use a #7 cup size and the rest is technique. But the welds aren't bad and railing looks real nice!!!
Reply:Originally Posted by mooseVPT For my purposes the trailing cover would be bulky and more bother than the results warrant. I will keep that technique on file for other joints though!moose
Reply:We're welding stuff like this almost every day. These welds are just fine, just polish them after welding. I've seen mig welded SS with c25 gas (realy gray welds) - after 5 years outside not a smallest sign of rusting... ...if you want good colour your welds must stay under argon shielding until they cool enought, so biger cup would help.
Reply:I noticed Lincoln has video on youtube about tig welding titanium where they put a really large cup on the torch. Maybe something like that could be used in this case as well for better gas coverage.[ame]http://www.youtube.com/watch?v=f0G2Tv82xUg[/ame]
Reply:I use that same extra large gas lens and cup with my torch Pete. I love it, my crew hates it. If you buy the WeldTec/TecTorch brand, you can buy replacement screens and retainers. They should last a lifetime. I replace the heavy mesh screen when I have a bunch of debris spit up inside compromising the flow.Last edited by shovelon; 04-26-2013 at 06:03 PM.Weld like a "WELDOR", not a wel-"DERR" MillerDynasty700DX,Dynasty350DX4ea,Dynasty200DX,Li  ncolnSW200-2ea.,MillerMatic350P,MillerMatic200w/spoolgun,MKCobraMig260,Lincoln SP-170T,PlasmaCam/Hypertherm1250,HFProTig2ea,MigMax1ea.
Reply:Take a stainless wire brush to it and PRESTO!All the "Colors" vanish!...zap!I am not completely insane..Some parts are missing Professional Driver on a closed course....Do not attempt.Just because I'm a  dumbass don't mean that you can be too.So DON'T try any of this **** l do at home.
Reply:Originally Posted by shovelon I replace the heavy mesh screen when I have a bunch of debris spit up inside compromising the flow.
Reply:Wow lots of opinions on this one.There are essentially two types of coloration you can see in stainless.The golden straw, reddish pink (some call it salmon) and blue are all from oxygen hitting the metal while it still hot.  You can actually estimate the temperature of the metal when the oxygen hit by the color.  These colors are sometimes called "heat tint"See: http://www.bssa.org.uk/topics.php?article=140%20-The graying of the weld is actually from too much heat.  Total heat.  That means if you turn down the amps and go slower, the heat seaps in deeper/farther.  Its usually better to run hotter and faster.However, those welds look really good overall.  I'm with zap on this one.  Stainless steel wire brush and be done with it.If you want to get rid of the heat tint as well, it can be chemically done.  Read up on passivating stainless steel.BTW, if it fits, consider a No. 7 cup as the minimum size.15-20 cfh is plenty.  Make sure when you are done, and the post flow timer is going, you keep the torch over the weld.  Consider adding a couple seconds to the post flow.Con Fuse!Miller Dynasty 350Millermatic 350P-Spoolmatic 30AMiller Multimatic 200Hypertherm PowerMax 1000G3Miller Maxstar 200DX
Reply:That weld looks great to me, after all your not making Swiss Watches  Miller Dynasty 350Twenty Six HammersThree Crow BarsBig Rock
Reply:Just did some Stainless.......  Miller Dynasty 350Twenty Six HammersThree Crow BarsBig Rock
Reply:And a Titanium exhaust pipe, this was already posted but figured I would show it again. Also done with a large cupped gas lens.....  Miller Dynasty 350Twenty Six HammersThree Crow BarsBig Rock