What should I be doing different?

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I am welding my first set of stainless pipes for my bike. I've been reading a lot on header fabrication and stainless tig welding on this site and many more. I thought I had it all figured out and even though I'm not a very experienced tig welder I thought the welds would at least be a little better. Of course I'm shooting for the rainbow/salmon stack of dimes look but it's just not happening... not even on any part of the welds! Here's what I got: -stainless 304 16 gauge 1-3/4 pipe. -miller dynasty 200dx-1/16 red tungsten-308L filler both .040 and 1/16-gas lense -#5 cup-12-15 cfh-back purge- 60 amps +/--trying pulse as well 33/33/33 Attached ImagesLast edited by 66mynd; 05-24-2014 at 03:35 PM.Reason: Wasn't done
Reply:Took me forever to upload these but here's what they look like Attached ImagesLast edited by 66mynd; 05-24-2014 at 04:07 PM.
Reply:Actually after I posted I kept searching for threads on this type of stuff. I made some changes and things are looking better already. I switch my 5 cup for an 8 and upped my sfh to around 18. Seems to be keeping the weld cooler as I am also trying to move faster. I'll post some more pics soon.
Reply:Yep. Looks kinda hot
Reply:Too hot too slow not enough gas.You should also REALLY CLEAN the inside of the tube!!!!!...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 zapsterToo hot too slow not enough gas.You should also REALLY CLEAN the inside of the tube!!!!!...zap!
Reply:Much better quality of weld with the changes. I would still turn down the heat a tad.ChrisAuction Addict
Reply:Originally Posted by 66myndHow do I clean the inside of the tube? Do you mean wire brush it or something before I tack it together?So I was pretty happy with round two. I did like you mentioned and turned up the argon to like 18. I ran the 8 cup and just kept it moving. I really think that the extra gas made the biggest difference. I almost felt like in some instances the HAZ was bigger than before but the weld came out way better. Thanks
Reply:Yeah, you still look a little hot as evidenced by the concave shape.  Keep playing with it, I'd try practicing on some drop pieces of pipe before continuing to weld up your actual exhaust pipe.Matthew MortonTexas A&M '06Logsdon Seminary '13"Who Dares Wins""AFTF""WH2PH"SA 200 (Code: 5337)TB 302CP 302 w/22A Wire FeederMillerMatic 200Miller Syncrowave 200MillerMatic 252BurnTables 4x4 CNC MachineHypertherm 65
Reply:If I was welding that, the argon would be as high as I could possibly get it. Jumbo gas lens with a 10 or 12 cup.
Reply:Too hot still. You need to weld enough that is covered under your cup. Larger cups are better. So you have a #8 cup, so me personally I wouldn't weld more than 1/2" at a time. And then let it cool. Even 2 minutes makes a big difference. Or go to another part weld then go back to the first piece you welded.Torchmate 2x2 CNC with Flashcut CNC controlsHypertherm Powermax45 Esab ET220i Razorweld 195 MigRazorweld 200ac/dc TigTormach 770, Tormach xstechRazorweld, Vipercut/Vipermig, SSC Foot Pedal Dealer
Reply:Awesome thanks everyone for all of your advice. I can see how going to a bigger cup would help. I have the gas saver kit for my new ck torch with the jumbo cup and I'll try it out. I finished most of the pipes but I've got a few more pieces to weld on to it and I'm also going to be making pipes for my friends bike. I'd have to say one of the the biggest challenges besides the welding is contending with distortion. These pipes were fabricated and tacked while on the bike. I made mounts that bolt them together and to the bike in six different spots not counting to the head. After I had finished most of the welding I tried to bolt them back on the bike but it did not fit. It distorted so much that some of the mounts were an inch off of where they needed to be to bolt up. I read that stainless distorts 1-1/2 times that of steel and that seems pretty accurate. There are two reasons why I believe this happened: #1: my fit up was not the perfect fit up that everyone says is necessary. What I had read recently in one of my books, "advanced automotive welding by Jerry Uttrachi" was that the maxim allowable gap on .065 wall tubing is .02. My max gap was around .04-05 in two spots. So one reason why I believe it may have distorted in some areas was the added heat to one side of the pipe due to a less than ideal fit up. #2: I have a few tabs that are welded on the pipes which would add extra heat to one side of the pipe causing it to distort. How am I going to deal with this? What I started to do with great results so far was to employ the techniques of "flame straitening".  I had read about it and also have some experience cambering and curving steel with it. By using the tig torch to heat/reheat certain areas I was able to get one of the pipes to move back to where it was. I had to run out so I didn't get to finish the job but I'll be back in there Monday. I really appreciate you guys helping me out. I'll post some more pictures as I progress, maybe others can learn from my experiences.