Cracked tig weld on chromoly bicycle frame?

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I'm not a welder but thought maybe some people here could help.  I just bought a new, never ridden, bicycle frame and immediately noticed a suspicious looking black line, or crack or void space on one of the welds.  This frame is tig welded chromoly steel tubing.   I'm trying to ask around locally but I feel like I need either frame builders' advice or veteran welders' advice.  I'm just trying to develop some more context in order to decide if the crack might grow/propagate with use and fail or, if it's inconsequential?  I realize it could be a source of corrosion but I can deal with protecting it from the elements.  I understand it could be a cracked tack or excessive filler which wouldn't be a big deal?If you're familiar with bicycle frames, the weld in question is where the driveside chainstay connects to the bottom bracket shell.  The black line is very small and very difficult to get a clear photo of.  I can't feel any void with my fingernail so I guess the clear coat adhered over the line.Last edited by newbike; 01-21-2013 at 11:33 AM.
Reply:Weld cracks don't normally propagate like that. Most likely someone failed to prep the metal well enough prior to paint. Either way, I'de remove the paint at that spot and fix it as it will definitely get worse over time. Once the paint is removed there will be no question as to whether or not you got rust or a face plant waiting to happen.EDIT:Or if it's brand new, make them fix it regardless.Last edited by Snuffy; 01-21-2013 at 12:32 PM.NickESAB CaddyTig 2200iPowermax 45MM140 (Sold)
Reply:Not the obvious dark black line but on the edge of the weld you can see a hair line something, either a paint problem or a crack in the weld.
Reply:Warranty, warranty, warranty.Take it back and get a replacement. I have tons of experience with this. How new is it? What brand? And where did you buy it?There is a bike builder on this forum. http://www.zanconato.com  Zank is his name. Send him a PM, he can advise you further.  http://weldingweb.com/member.php?u=36168Last edited by shovelon; 01-21-2013 at 01:21 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:I'm with Terry. Inconsequential or not, you shouldn't have to accept something like that on a new frame. I would take it back.
Reply:The frame is totally new.  It's never been built up with parts.The area that VPT circled doesn't jump out at me when inspecting the frame in person.  I can't see any obvious cracks or voids in that area.  It definitely could've been painted better in that area though.I sent Zank a PM.  Thanks!
Reply:If its a chromoly bike frame, I'm sure you paid top dollar for it.. Send it back and get what you paid for.tackleexperts.comwww.necessityjigs.comhttps://www.facebook.com/groups/mach...dingequipment/
Reply:It "could" be " paint bleed through" maybe from a marker, or pen etc... Can you feel the edge with your finger nail?? Edit i just reread your op... I doubt that's base/clear looks more like single stage paint, unless it has a serious amount of paint OR powder coat, you should be able to feel the edge...Last edited by DemonSpeeder; 01-21-2013 at 09:28 PM.Lincoln pro mig 180Lincoln Square Wave Tig 300/wp 20/home built water cooler Victor, Purox, Harris, O/A welding/cutting setupsVintage Craftsman drill pressVintage Craftsman/Atlas 12"x 36'' lathe7''x 12'' w/c band saw Everlast 140 st
Reply:My buddy Lou owns a bicycle shop and sending bad frames back is nothing new.I see them more often than not...DO IT....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.