TIG bead critique please

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Hey there, new around here, and new to TIG as well. Picked up a cheap tig to see how it goes, just wondering if you guys can shed some light on my welds and let me know where im going wrong. Pics are of .180 wall mild steel tubing, and 3/8" steel plate. Settings were 110 amp on the tube and 165 amps on the plate. Using 2% thoriated 20 CFM 100% Argon. with ER7OS-2 rod on a Chinese inverter based machine.
Reply:Looks like you need to add more filler and get your dips a bit closer together to start. I see lots of signs of undercutting in most of the examples, and the beads look too concave. I also note at least 2 spots where you contaminated your tungsten in pict 4 ( the black sooty spots) You need to stop and regrind at that point as well as clean up the material. Consistency is mostly lots and lots of boring repetitive practice.I also see some issues with prep. I see a lot of heavy flat grinding marks on the tube. Since tube is so thin, you need to take care not to thin it down where it's not necessary when prepping. A sanding disk is less aggressive than a grinding disk for this sort of thing. Also I'm not sure what sort of part you are building, but the milled slots that go way past the plate will be an issue. Those slots should stop at the end of the plate and get welded all the way around.Part of me is also somewhat concerned just what this is for. If this is for a vehicle, especially if this is for suspension, it's a poor "learning" project. The tendency of many is to grab a new machine and dive right into the project they want to do before getting the skills required to do them. I'd strongly suggest cutting thru these sections to see if you are getting good penetration on the tube. I've seen many where the weld is just filling in the V and there really isn't any depth in the tube..No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
Reply:I agree with all the above..Slower..Steadier..More time behind the torch..You have the basics down..You have to eliminate the hole at the end of each weld..That's where the cracks start..There is no better teacher than seat time..Post pics of progress and we will take it from there.....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:Looks like a motorcycle frame......definitely not the project to learn on.http://all-a-cart.comWelding Cart Kits and accessories
Reply:Thanks for the replies, much appreciated. Having a tough time with the undercut, i think i can get rid of most of it by adding more filler and getting the beads closer as mentioned. The ground down area is where a heavy fully boxed gusset goes, i agree it would be a horribly poor prep job for a end result. The milled slots also have a 3/8" rod that goes down in the now open area and gets fully welded. I did quite a few test pieces to check for penetration on both the tube and plate an it is getting in there really good.Ill post more pics, if anyone can add to this, ANY and all advice is much appreciated!
Reply:1-Since one's gone to the effort of having a slot milled,then why not do a decent chamfer/ radius around all the edges,for functional reasons, in addition to a more professional appearance?[Edge breaks, chamfers, radii are all considered good machining and designpractices. There's a slew of fast, easy ways to accomplish this.Just be-cuz.....you may not see them on some work posted here,doesn't negate them.]http://weldingweb.com/attachment.php...1&d=12836427262-Craters--as Zap sez---are bad news, functioning as crack initiation points.The suck hole in the crater can extend to the inside, creating a leak in a pressuretight weld. Fade back out when stopping a weld stops crater formation.http://weldingweb.com/attachment.php...1&d=12836427433-Undercutting into the tube wall is also circled in this crater pic. Attached ImagesBlackbird
Reply:Great stuff thanks Dave. The milled slots have a rod that goes through that is part of adjuster assembly. Once in place it will be welded together. Although it looks like a haphazardly milled, the slot its actually that way for a specific purpose. As for chamfering that will also be addressed.Working on the crater problem, i have developed a bad habbit with this process in that i pull my torch away to "cool" things down. This all stems from my experience mostly coming from Oxy welding. When i do this with the tig it just makes a mess as the cone widens and eats away the parent substrate. I am also finding myself chasing the pool in a "C" pattern which i think is also contributing to the undercutting.With that being said, what is considered the most use way of finishing a bead.Again thanks to allLast edited by Black2; 09-04-2010 at 08:22 PM.
Reply:Originally Posted by Black2Great stuff thanks Dave. The milled slots have a rod that goes through that is part of adjuster assembly. Once in place it will be welded together. Although it looks like a haphazardly milled, the slot its actually that way for a specific purpose. As for chamfering that will also be addressed.Working on the crater problem, i have developed a bad habbit with this process in that i pull my torch away to "cool" things down. This all stems from my experience mostly coming from Oxy welding. When i do this with the tig it just makes a mess as the cone widens and eats away the parent substrate.With that being said, what is considered the most use way of finishing a bead.Again thanks to all
Reply:The tube to tube welds at the top look a little hot to me[gray color]. It's not necessarally your amps , could be to slow of a travel speed or both. Welds aren't all that bad and a little fine tuning and you will have it down.
Reply:Assuming your machine has a foot pedal, what the guys are talking about with 'fading out' at the end of the weld, is slowly let off the foot pedal in a controlled manner to slowly cool the puddle and add filler during this time until the puddle is nearly solidified.MM350P/Python/Q300MM175/Q300DialarcHFHTP MIG200PowCon300SMHypertherm380ThermalArc185Purox oaF350CrewCab4x4LoadNGo utilitybedBobcat250XMT304/Optima/SpoolmaticSuitcase12RC/Q300Suitcase8RC/Q400Passport/Q300Smith op