First aluminum TIG beads

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Just unboxed my first TIG machine, a Longevity 200 SX AC/DC stick/TIG unit.  These are my first TIG practice beads on aluminum from left to right on 1/8 inch plate.
Reply:Amps?.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:Something doesn't look right, the etched area is very inconsistent.Airco Ac/Dc 300 HeliwelderMillerMatic 200 (stolen)Miller Maxstar 150STLMiller AEAD200LE (welding and generating power) Hobart MIG
Reply:You need a larger piece to practice on.Torchmate 2x2 CNC with Flashcut CNC controlsHypertherm Powermax45 Esab ET220i Razorweld 195 MigRazorweld 200ac/dc TigTormach 770, Tormach xstechRazorweld, Vipercut/Vipermig, SSC Foot Pedal Dealer
Reply:Good for you.  Now add in more cleaning action, and practice for consistency on a much larger piece so it doesn't get heat soaked as quickly (equivalent of letting the heat input get out of control fast). 1st on WeldingWeb to have a scrolling sig! HTP Invertig 400HTP Invertig 221HTP ProPulse 300HTP ProPulse 200 x2HTP ProPulse 220MTSHTP Inverarc 200TLP HTP Microcut 875SC
Reply:Got it. Bigger practice piece.  More cleaning action.  I was at -3 on the dial, go to zero?Amps were variable but max about 100 amps.  I'm guessing variable etched area was torch angle/height inconsistency?  I see why people think the WP-26 torch is a club, any recommendations for a smaller one?What should I target for etched area?
Reply:I thought that might be the case. Your amps are way too low for 1/8". We have students set the machine for 150 amps and I go even higher, close to 200. General rule of thumb with tig is 1 amp per .001", and with alum, you add about 20% to that to get the puddle to form and then back off as you weld. So for 1/8" you get 125 amps for the .125" material, and then add 20% or another 25 amps to get your rough starting point.Alum is a great heat sink. What happens when you try and weld slow is that the alum sucks the heat away from the puddle and it takes forever to get the puddle to form. When it finally forms, the piece is super hot. You have most of your coupon almost at the melting point. With higher amps, you floor the pedal and use the extra amps to over come the ability of the alum to wick away the heat and the puddle forms almost instantly. Then  to move quickly and back down the amps with the pedal as the alum heats up controlling the pedal. We use 150 amps for students so they can simply mash the pedal to the floor and then wait a second or two for the puddle to form and GO! Since I have more experience, I can use more amps and react quicker when the puddle forms.Keep in mind heat from previous beads also is your enemy. I tell students if they can pick up a piece with their bare hands, it's cool enough to run bead #2. That residual heat "helped" you get the puddle to form faster once the piece was already screaming hot, but F's with a bunch of other things.The reason you want to limit heat input with alum is that alum is very heat sensitive. Many alum alloys go to annealed state and loose they temper at temps as low 300 deg F. For this reason you want to keep the HAZ down as narrow as possible, and let the alloying components in the weld bead deal with the loss of temper. Heat the whole piece up like you did, and you lost all the strength from the original material..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:Originally Posted by OscarGood for you.  Now add in more cleaning action, and practice for consistency on a much larger piece so it doesn't get heat soaked as quickly (equivalent of letting the heat input get out of control fast).
Reply:Sand, a couple of things before welding, Zap has referred to these, but I will suggest they should become habit in all aluminum TIG.De-greasing before mechanically cleaning is basic; just like gas for the torch or tungsten and filler on hand; you need to remove the mill scale first and that is easiest done by mechanical means like a power or hand brush. But, if you don't degrease before these operations? you'll just contaminate the cleaning brush and smear whatever is on the surface around.The wire brushes should have 0.014" diameter wire or finer, and they should not be those SS brushes (use exclusively SS ) that are intended for SS pipe and structural work since those wires are so thick they gouge, cut, and excavate aluminum and so the advice will appear from time to time not to use power brushes.Don't use the wrong power brush= true. Don't use a power brush= over generalization.After de-greasing, and mill scale (part oxide part coating)removal; the weld areas should be clean 'white metal' (industry term not strictly based on the silver colored metal looking white) and are ready to weld.Oxide forms in a few seconds so good practice, unless on art pieces as sometimes posted here by the really proficient welders, is to re-brush for a few strokes the areas you will weld.  This will abrade and ridge the oxide film that has formed since cleaning originally and allow the gas and arc to lift the furrowed oxide film easier and more completely.Your uneven clean tracks on the sides of the welds are probably uneven gas cut/torch control and will become more uniform when you torch hand gets more steady.Last but not least, by practicing welding in this wandering no-guide method; you are teaching yourself LACK of puddle control. If you  draw lines, or make a scribed line or do anything to create a nice reference line, then keep the toe of the weld to that line, you will advance in your welding faster than if you keep this wandering method shown.What joint, in anyone's welding experience, involves randomly wandering around the parent metal?  IF you can't keep the puddle controlled to a line on the practice plate, then its not going to be any easier to do this on the first butt, lap, fillet seam either.  Practicing welds without cleaning results in gas inclusions, and lower strength welds, and so does practicing random welds result in less contribution to learning welding on a seam.yes, I agree that you have to learn all the related events of TIG more or less at once, but skipping the need to track as line, seam edge, joint shape only makes that a bigger hurdle when it comes forward in your learning. Why not start right?Degrease, mechanically clean, make reference lines (if on a plate) and then before you light up- hand brush a few strokes and when you practice keep your eyes moving from 12:00 to 6:00 O'clock don't bother to look much at the arc, mainly the edges of the puddle. Learn to let your reflexes rely on these images to correct and form the puddle.My few cents about the TIG learning process. For the first few beads there's a lot to be happy with in your progress, as I see the beads.  Larger plates can be rotated one bead each then cooled 'til only warm to the touch, otherwise the arc control become less and less effective as you accumulate more and more retained parent metal base temp.Cheers,Kevin MorinKenai, AK
Reply:Originally Posted by sand_man_redI see why people think the WP-26 torch is a club, any recommendations for a smaller one?
Reply:Originally Posted by 7A749Wow.I've done some pretty heavy welding on my 350 with a standard 17 torch before the water cooled one showed up. Of course, I would blow shop air over it once it started getting really warm between welds.
Reply:Round two.  1/8 inch plate.  Max amps 130.  Increased cleaning both mechanical and 'cleaning' setting, -2 instead of -3.How important is the shape of the tip with 2% lanthanated tungsten?How do I control the little dimple at the end of the bead?First few bead are no filler :-)
Reply:The 200sx is a great machine. I had one and set the balance to -3 and it was a great all around setting.I'd turn up the heat just a bit on that machine though to about 130-140. The knob is just a little off from actual current. Or you can stand on the pedal and look at the display.The dimple at the end is where you break the arc and the tungsten was point. You can taper off slowly and add a few more dabs of filler at the end or move the torch in a circular motion, dap filler and back off the pedal. A few different ways to do it. Very good work so far! Also for consistent work, try dunking the piece of aluminum into a bucket of water, blow it off with compressed air then weld again. This way the piece is at the same temp for each bead. Once it's hot it looks like those 3 beads on the left.Torchmate 2x2 CNC with Flashcut CNC controlsHypertherm Powermax45 Esab ET220i Razorweld 195 MigRazorweld 200ac/dc TigTormach 770, Tormach xstechRazorweld, Vipercut/Vipermig, SSC Foot Pedal Dealer
Reply:looking pretty good. for the crater try and taper of as slow as you can on the pedal.- Christian M.C3 Welding & Fabrication - CNC Plasma Cutting-Mobile Welding-Custom welding and fabwww.c3welding.com
Reply:Originally Posted by MinnesotaDaveI just ruined a wp-17 trying it for a while on AC. The collet body seized in the threads...
Reply:Originally Posted by SquirmyPugI've done that.. A couple times..  poor little #17s don't like 200+ amps.. I found out they make a tap to clean the threads of torches, don't know how well the back cap and collet body fit after doing that though.
Reply:The shape of the tungsten: pencil point, with a clipped end, about the size of the ball you're getting at the settings you're using. (changes with different amps and cleaning %) End crater: take your time at the end of a weld, as well as the beginning. Aluminum flows like water when you get it hot enough, that's great for the middle of the joint where you dab fast to stay ahead of the heat (center of the bead in the center of plate #2). At the beginning you need to floor the pedal and wait for the parent metal to melt in a bit, dab slowly at first, picking up speed as the metal heats up. Towards the end of the bead you need to taper off quite dramatically, especially on a small part, the last two dabs you are barely keeping the arc lit. SqWave 200Millermatic 190Airco 200 ACHypertherm PM45Boice-Crane Band SawVictor O/A
Reply:Thanks to all for all the help.  Here's a bead on a current project.  It's 1/8" plate at a 90 degree outside corner.  Set max amperage on pedal to about 115 amps.  3/32 2% lanthanated tungsten, -1 cleaning effect, 15 cf/hr argon, #7 cup.  I go to the max at the start, back off some once started and then back way off at the end.
Reply:Looking good!SqWave 200Millermatic 190Airco 200 ACHypertherm PM45Boice-Crane Band SawVictor O/A