My TIG welding aluminum. Critique.

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I though I did ok with this weld, but I've never taken a class and am self taught.I'm wondering why the welds aren't shiny.Was I moving too fast? Not enough gas?I deburred with edges with some sandpaper.I prepped by brushing the outside of the pipes with a stainless steel brush.I welded this at around 55 amps, at 105% frequency, at 50% wavelength (excuse me if I confused these terms. Please let me know if I need to provide more info)I've included a picture of my argon flow rate.
Reply:A bit cold, you need more heat and turn down your gas, 11-13 max on that thin material.John -  fabricator extraordinaire, car nut!-  bleeding Miller blue! http://www.weldfabzone.com
Reply:Looks better than my first time..Yeah..About the heat..You could use more but watch out as you go..The piece will continue to get hotter and hotter so you need less and less pedal as you go..Too much at the end = Puddle on the floor..Or your lap...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:Thanks guys. That definitely wasn't my first time. I just got back into working on the car so I really haven't welded much this year. I was very much out of practice.This is a stupid question. I can't read my flow gauge. What was my CFM? I just can't read that thing.Should I be reading the red, or the black area? I have this little chart that tells me my flow rates for certain metals, thicknesses etc.My chart gives me rates in LPM. Do I need to convert?And another question: How can you guys tell I didn't use enough heat, and how do you know my gas was too much, simply because of the picture? What happens in theory to the metal/weld when you have too much gas?Last edited by Underwhere; 05-03-2008 at 12:02 PM.
Reply:Right now it's at 19 CFH(Cubic feet hr.)The black numbers are the argon reading..The red is for CO2..Thats why the word argon is in black and CO2 is in red....I leave mine set at 10-12 all the time unless certian situations come up..You are wasting gas with it up that high and you will see that it will weld a little better down low.....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:We can tell not enough heat by looking at the edges of the bead.  They should be blended in instead of just edges.  The filler should flow and become part of the base metal.  There is a fine line between enough heat and too much.  You need more.  Otherwise its lookin good.DavidReal world weldin.  When I grow up I want to be a tig weldor.
Reply:Thanks guys. I'll try that. I have to weld up another piece tonight.
Reply:Originally Posted by zapsterLooks better than my first time..Yeah..About the heat..You could use more but watch out as you go..The piece will continue to get hotter and hotter so you need less and less pedal as you go..Too much at the end = Puddle on the floor..Or your lap...zap!
Reply:Well you are right in one respect..It does take more to get it hot than steel..Once it is hot however less pedal is needed as you get further and further along the weld..I have had classes where there were "melted blobs" on the floor from too much heat..Try this and keep your body parts out of the way..Start a bead on aluminum and Do Not lift or accelerate the heat..Stay steady and tell us what happns to the piece..If there is a piece left.....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:I agree with others' thoughts on the heat.  The flow rate, I run higher though.  When it's down that low, even somebody walking by can sometimes disrupt your coverage.  I figure that it's worth a few dollars per tank, for the insurance.  But..if it works for you, and you like it, go with it.  It doesn't look like you have had any coverage problems.  Your flow rate shouldn't be any different for thin metals than thicker, since it only covers the surface of the weld, and not the thickness.
Reply:Would someone comment on the oxide cleaning zone? It looks a little wide to me. If Underwhere turned up his balance (less cleaning, more penetration), would this accomplish the 'more heat' recommendation?Thanks, Craig9-11-2001......We Will Never ForgetRetired desk jockey. Hobby weldor with a little training. Craftsman O/A---Flat, Vert, Ovhd, Horz. Miller Syncrowave 250
Reply:Changing the balance will not add any more heat, unless he has a machine like the Dynasty 350, where he can adjust the positive and negative amperage separately.
Reply:Originally Posted by EngloidChanging the balance will not add any more heat, unless he has a machine like the Dynasty 350, where he can adjust the positive and negative amperage separately.
Reply:As Craig said, for a given amperage setting, changing the balance to more DCEN will transfer more energy to the weld.  And I agree, the oxide cleaning zone is wider than it needs to be, so there is room to adjust the balance for less DCEP cleaning.
Reply:Originally Posted by UnderwhereI have a thermal arc 185. I don't believe I can do that.I haven't played much with the frequency. I believe it's around 105 hz. The higher you go, the more pointed/accurate the arc is. Is that correct?What would you guys run for a frequency in this situation?
Reply:Originally Posted by David RArcmastet 185 has adjustable wave balance.  Its the % of + wave.  65% + wave will ball your tungsten and that is as high as it goes.   25 to 35% works best for me.  This DOES put more energy into the weld.  More - wave means more penetration and less heat into the tungsten.  That would be 25% of the wave is + and 75% is -.  If your wave balance is too much - you won't get enough cleaning from the + wave and will get black spots in your weld.  You then have to clean your aluminum better or turn the wave balance up for more + wave and more cleaning.Yes, more hz makes for a more concentrated arc.  I need to be under 40 to be able to weld 1/4" aluminum or I don't have enough heat.  Turn your frequency down and your bead will be flatter or look so cold.The TA-185 is a great machine.  Play with those adjustments to see what they do.  Once you figure it out, you can dial in the arc you want.David
Reply:Originally Posted by UnderwhereSo what would you recommend for my situation? I'm welding mostly thin aluminum intercooler piping. 1/16 thickness or around there.say 35% wave balance and maybe 80hz for frequency?