Newbie Tig work- what do the pro's think?

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Please let me have it-  the more critical the better, I can handle it.I know some of them are far away but I wanted to include as much as possible...Thanks in advance!
Reply:Most of it looks good.  First picture has a lot of undercut.   Get rid of that.  DavidReal world weldin.  When I grow up I want to be a tig weldor.
Reply:Yea i agree. Your getting there. Just watch that undercut.Ya gotta spend money to make money!
Reply:Thanks for your replies! By undercut you mean the fact that the weld bead is concave rather than convex? Does that mean I am running it too hot/slow?
Reply:Undercut is the gouged/underfilled areas beside the bead where you melted the base metal and left an unfilled low spot. It can be from lack of filler wire, bad technique, or too hot. All-in-all not too bad. As said, eliminate the undercut, and work on your consistency.
Reply:At most to every stop point--you are not fading out, causing a crater.       But--since these guys-above only harped on the undercut,I guess the craters get a free pass. Craters probably don't make squat difference-anyway, maybe just cosmetic bling, otherwisethe expurts would have said so.     On the other hand, however, craters seem to be ignored by many on this forum.Blackbird
Reply:On the craters- you are 100% correct nice observation! I always forget to fade out or doubleback and it makes my start and stopping points obvious and adds porosity- I also used to pulling away quickly before the shield gas stops flowing but I don't do that one as much anymore....Last edited by hpfiend; 12-08-2011 at 02:55 PM.
Reply:I had to do some research but I understand now about undercutting- I think I am moving too slow and not adding enough filler...
Reply:Looks like you are dwelling too long in one spot and creating a large inconsisten HAZ. Try keeping your speed and feeding of the rod consistent. Hope this is just practice and not something important as it almost looks like you're trying to build a hitch. Might not be the case...just an observation
Reply:CRATERS ARE BAD...... so is undercut......A young green pipe welder asked an old salt one day...How can I make the weld on the bottom of the pipe look like the top.......The old salt replied....Screw up the top......
Reply:Craters are deffinitely bad. They should not be overlooked, nor should the undercut. Overall, it looks really good for a beginner, so good job!  Things to watch for: carbon steel undercuts pretty easily. It looks like you were welding too hot for that and/or too slow with not enough filler. For a pro, you can weld hot as hell, but move fast and put down a lot of filler and be fine. But, for a begginner you should turn your heat down and focus on no undercut and smooth steady beads.  The craters can lead to cracks, leaks, and generally look bad. Like stated, slowly let off your pedal to get rid of it. Or, if you're running scratch start pull off the weld SLOWLY until you can break the arc with no crater.   Craters will cause you to fail x-rays or other ndt testing so deffinitely work on that.   But as said before, you're doing good, keep up the work and focus on whats been said here.                   Doug
Reply:You are trying to do too much with one pass. Use a multi-pass approach and make smaller, cooler stringers.Two turn tables and a microphone.
Reply:Some of the welds look pretty good. Some, not so much. Think about what you're doing differently between the "good" and the"bad" and work on consistently being able to reproduce what you DID to accomplish the good weldments.There is a lot of self discipline and self criticism involved in welding. You can teach yourself how to be consistent, no-one else can.Last edited by papabear; 12-08-2011 at 10:11 PM."SOUTHPAW" A wise person learns from another persons mistakes;A smart person learns from their own mistakes;But, a stupid person.............never learns.
Reply:Thanks all- It was getting pretty hot... I always have a hard time tying short stringers together so it looks uniform- my start and stops are always obvious- I think most of that is the craters but also knowing where to start so my ugly version of the stack of dimes looks uniform-do you add a dime to the end overlapping the last a little or do you remelt a few dimes back and start over?  Also- does it look like dimes to anyone else when welding? Maybe my helmet is too dark at its lowest setting (one of the first auto darkening units) but I can't get that level of resolution with the helmet on it is mainly by feel until I take the helmet off- I also notice that as I weld my head gets get closer and closer to the project as I try to see- is this just me- so much so my back kills after about 30 minutes to about an hour of welding. I have been tempted to buy another helmet but you know how inexperience lends to blaming the equipment ;-) so I have not.That's interesting about the good and bad- before I posted these (which I am very glad I did)  I thought the welds in the first picture were the good ones but I didn't know what undercut was- now I think the top right weld in the bottom picture is a good one and before I would think that was a "cold" weld-I am not trying to be antagonistic but intead curious-- How do you know you are getting enough penetration if you lay it on top like a surface fusion weld with filler on top? Previously I thought it was better to go deep and add more filler than I am or to run colder and use the same amount of filler?  Example- I made a set of custom exhaust headers using very thin wall pipe and an oxyacetylene torch... I tried to stick weld with a stich welder and very low amps, tried mig without gas as low as it would go and kept burning through- I then tried the OA setup with a small 0 or 00 tip and added some mild steel filler- there was little to no burn through and the welds looked great and flat but they cracked shortly after being put into use because they were so thin I thought... so maybe the penetration is correct but I need to dip the filler more slowly and deeper just before it builds up to hit my tungsten...???oh yeah what is HAZ?Last edited by hpfiend; 12-09-2011 at 11:24 AM.
Reply:Originally Posted by hpfiendoh yeah what is HAZ?
Reply:Yep craters and undercuts need attention..Slow down.Get comfortable.Space your dips with a little rythm in'em.Make sure you can get from point "A" to point "B" without stopping..Add filler and watch the sides of the puddle to fill in the undercut before moving to the next dip..I know I know easier said than done..In reality you need to look at what you are doing..Where you are going..And where you have just been all at the same time..Have fun and don't get discouraged..You need to start somewhere.Now lets really start digging..What amps did you use..Filler size?Material thickness of the tubing?...zap!Last edited by zapster; 12-09-2011 at 04:31 PM.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 zapsterNow lets really start digging..What amps did you use..Filler size?Material thickness of the tubing?...zap!
Reply:Under-fill: you seem to have several problems related to this, one it was too hot and there was too much puddle for your filler to handle with a straight center dip and it looks like you try and dip the puddle in differ locations for different amounts of time   Undercut: the torch being to far from your material, arc length severely affects under cut Craters: do a second dip when you are at the point that your going to stop then hold the torch there and slowly let off the pedal Excessive heat: 185amps is a lot of heat for that job i think looks to be 1/8" for that thickness i would put 140amps on the machine and use the pedal only at full to get a good puddle going if the metal isn't preheated Arc length: i like a arc length of 1-1.5 times the tungsten diameter Restarts: if you need to stop leave the filler in the puddle so when you restart there will be no distinguishable restarts also if you do restart with a tungsten out of the puddle remember to clip the discolored part off  but with that in mind they really aren't that bad. you need a good rhythm. good luck post new projects you do in this thread so we can see your improvement, have fun and weld on.miller xmt 304 w/ 22a feederdynasty 200dx tig runnerspeedglas 9100xvictor journeymen O/Aesab shadow 5000 shape cutterClausing Drill Press setAVIA d.r.o. milling machine ercolina ercobender 76baileigh hsp-66mJD2 notchmaster