what am i missing?

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Welding a crossmember on a hot rod frame I'm building and hit a snag. Everything has been welding great until i tried to do the inside of the crossmember to frame joint. Weld starts hissing and spitting like i don't have any gas coverage.  Gets worse the more pedal i give it (TIG btw). You can see in the pics outside went fine but inside turned to crap. I can barely fit the torch inside of the crossmember with enough angle and have to use lots of stickout. Too much stickout maybe? I even dammed the area with aluminum foil and a second bottle of argon flowing 8-10 cfh. It seemed even worse with this.  Test on a scrap piece, no problems at all.TA185160amps3/32 thoriated1/16 er70s-2 fillerCrossmember= 3/16 steelFrame =3/16 steelSorry, pics should be rotated right 90 deg. Couldn't see an option to do that after loaded. Attached Images
Reply:Looks like lack of shielding from long arc/ too much stickout. Before going through too much trouble try welding a joint you can reach without allot of stickout to see if it welds better.Airco Ac/Dc 300 HeliwelderMillerMatic 200 (stolen)Miller Maxstar 150STLMiller AEAD200LE (welding and generating power) Hobart MIG
Reply:This is the best i can do with what I've got. Attached Images
Reply:I ran across the top of a scrap peice with less stickout and it went fine.  Should i try again damming it up with foil and flooding with argon?
Reply:I wouldn't. If you have a gas lens try that with #6-8 cup and 20-25 CFH. If you still can't keep it shielded then reduce stickout and tilt the back of the torch out of the joint(back cap should point more toward you) and feed filler from top/bottom.Airco Ac/Dc 300 HeliwelderMillerMatic 200 (stolen)Miller Maxstar 150STLMiller AEAD200LE (welding and generating power) Hobart MIG
Reply:Yep, not enough gas. Looks like a #6 cup. 2 to 3 times cup size is what we use, so 2.5 times cup size which is 15cfh would be good. Stubby gas lens and cup would be best. I agree 7 or 8 cup do help.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:Does it have to be TIG'ed? Seems like a perfect use for SMAW with a 7018.Miller Multimatic 255
Reply:Well, just tried a bigger cup and gas lens with 25cfh and definitely much better but still getting some bubbling in the puddle. Doesn't have to be tig but i only have access to 110V flux wire mig and the TA185 does stick but i lack much experience with stick. If you guys could give me a few setup tips for stick I'll try it on some scrap and see how that goes. For now though I've got the fun task of grinding out these shatty welds
Reply:Did you grind the joint out before trying to tig it (with the new cup)? It won't weld good if you don't.What kind of stick electrodes do you have? For 7018 use DCEP. 3/32" you will want around 90 amps and 1/8" you will want around 120 amps.Airco Ac/Dc 300 HeliwelderMillerMatic 200 (stolen)Miller Maxstar 150STLMiller AEAD200LE (welding and generating power) Hobart MIG
Reply:I got as much as i could ground out with pointed carbide head porting bits. Grinding them out again, I'll post some pics to see what you guys think.  The last welds i just did, one side was good but very undercut on the top (crossmember) side so I'm starting to do more damage than good.
Reply:Here's where I'm at now. Trying to show undercut with filler rod.  Should i leave that weld and lay stick weld on top or grind it out? The other weld is obviously going to get ground out. Attached Images
Reply:If you are going to stick weld it grind it out so everything is uniform when you are done.Airco Ac/Dc 300 HeliwelderMillerMatic 200 (stolen)Miller Maxstar 150STLMiller AEAD200LE (welding and generating power) Hobart MIG
Reply:Hello ckr427, is this a build that is completely from new? I am asking because of the possibilities of internal contaminants that can melt and wick or otherwise be drawn into a weld puddle from areas other than those of direct contact or view. If this is an upgrade or modification of something existing and the original materials had undercoating or other materials on them you may not have completely gotten these removed and they could be contributing to your problems. Additionally, if you have enclosed parts and you are trying to make welds that will essentially seal those closed spaces you can experience a build up of pressure and this pressure can blow out the end of your weld creating porosity and problems with quality as you attempt to finish off the welding. If there is identification paint on steel that you are using be sure to remove it and if this steel has any sort of anti-rust inhibitor or some other sort of preservative be sure to remove that too. A lot of the time pipe, tubing(round, square, rectangular) will have preservatives on both the outside and the inside. When this is heated up during welding gravity can cause these compounds to melt and run down the inside or on the outside of these items and cause contamination of the welding pool. Just a few additional items to consider. Good luck and best regards, Allanaevald
Reply:I would guess that turbulence is the cause of your problem. Same thing that makes a torch flame blow out when you try to apply heat in a confined space. I would second the recommendation of a gas lens, and less gas rather than more. Too much gas flow will draw air in to the corner and dilute the argon. For tight spaces you can get a long nozzle for a gas lens, where the narrow part at the end is about an inch long.JohnA few weldersA lot of hammersA whole lot of C-clamps
Reply:This is all new steel. Probably some contaminants here and there but as most of you have stated this is a gas coverage issue.  I'm now getting good welds with 25cfh a gas lens and#8 cup.  Plus I'm playing around with bending the tungsten which has helped quite a bit. Only problem I'm still fighting is getting undercut on the top side of the bead which is fully a byproduct of my skill level and this tight spot. But this is how i learn best. Thank you guys for your help and pointing me in the right direction.  I'll try to update how this pans out but walking away from it for the night
Reply:When you tried to close off the box, the expanding gas trapped inside tried to escape through the seam that you were trying to weld.  You can drill a itty bitty hole to relieve the pressure, or set up a situation in which the gas inside is cooling while you weld. You may also be able to purge the seam for a very long time get enough Argon inside the enclosed area, so that the expanding gas within the enclosed area is mostly argon. Im just guessing, I have run into this problem before, but it could be many other things: a defect in the base metal comes to mind. infuriating Im sure.Constant Current Weldor.
Reply:Bending the tungsten??? What did I miss? 30+ yrs Army Infantry & Field Artillery, 25 yrs agoMiller 350LX Tig Runner TA 210, spool gunLincoln 250/250 IdealArcESAB PCM 500i PlasmaKazoo 30"  vert BSKazoo 9x16 horiz BSClausing 12x24 lathe20T Air Press
Reply:Have you tried welding from the inside of the corner out to see if it helps? Also be sure to weld around the ends.
Reply:The end of the frame rail is wide open so there shouldn't be any pressure issues, that has gotten me before though. The bending the tungsten was something i came across before on this site. Don't remember who posted it. Attached Images
Reply:Originally Posted by ckr427 Don't remember who posted it.
Reply:Well, I have to say I have never done that....at least not on purposeHobart Beta-Mig 2511972 Miller AEAD-200LEMiller 250 TwinNorthern Ind. Hybrid 200Longevity Stick 140Longevity Migweld 200SThermal Arc Pak 3XR
Reply:You have a lot of porosity there. You need to grind all that out before welding over it again. It appears to me you have too much stick out with your tungsten. If this were my project, id get all the porosity ground out and re weld with 3/32 7018 stick rod.That inside weld is a tough location to put in a nice tig weld.Last edited by snoeproe; 01-18-2015 at 11:19 PM.JasonLincoln Idealarc 250 stick/tigThermal Dynamics Cutmaster 52Miller Bobcat 250Torchmate CNC tableThermal Arc Hefty 2Ironworkers Local 720
Reply:There is a real good chance grinding will not take out the porosity. Sometimes it just hides the porosity, and it comes back with a vengeance.When you get porosity on the first pass, it will go into the parent metal.I have "gotten rid of" porosity by going over it using stainless filler.For yard art and patio chairs, that would be ok, but for critical work, nothing beats proper preparation and proper technique.Hobart Beta-Mig 2511972 Miller AEAD-200LEMiller 250 TwinNorthern Ind. Hybrid 200Longevity Stick 140Longevity Migweld 200SThermal Arc Pak 3XR