Aluminum job

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A machine shop dropped these off yesterday.  I have done 2  before each one at a different time.   Instructions: about an inch "tack" (customers word)  weld on each corner and in the middle.  Bevel each one before welding.These will be ground back to flush.  They tell me they hold stamps.  and all aluminum is 6061 so I use 4043.  All I have right now is 1/8 filler.All were marked and beveled before starting.  I used an aluminum disc on the 4.5" grinder to bevel the plate and sheet.  I clamped the two so there could be no gaps before welding.  Arcmaster 185.  AC 30% + wave, 90 Hz.  25 cfh argon, gas lenz, #8 cup.   Turned up, all she had.  I tried 50 Hz, up to 150 Hz.   It seemed to work best at 90 like usual.I tried 1/8" cerated with not much luck, then I went back to 3/32 red or black.   Nothing great till I balled the tungsten.  It welded better with a small ball like in the picture.  These are what I used for the whole job not counting the couple 1/8".  ITotal time a little over 3 hours.I jumped around with the welds to keep it from warping so the whole thing heated up pretty even.  Last weld went on easiest.DavidReal world weldin.  When I grow up I want to be a tig weldor.
Reply:Interesting job David.Oh and nice 'tacks'I'm curious, welded horizontal orflipped up and done flat?I'm just a rookie but that's a lotof cleaning action with a wide etched area, no?I assume a ss brush and wipedown prior to get going or relyon the ac balance?How do you know the blacksmith's dog? When you hollar at him he makes a bolt for the door!
Reply:Did you do this so ugly because the weld will be ground off? I am not trying to be mean, I just try to make all of my welds look good, even the ones that wont be seen.
Reply:No pure tungsten?Vantage 500's LN-25's, VI-400's, cobramatics, Miller migs, synch 350 LX, Powcon inverters, XMT's, 250 Ton Acurrpress 12' brake, 1/4" 10' Atlantic shear,Koikie plasma table W/ esab plasmas. marvel & hyd-mech saws, pirrana & metal muncher punches.
Reply:His TA 185 is an inverter Duallie..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:AC balance around 30 or 35% + wave.I was not too worried about looks.  I wanted penetration because the welds will be totally ground off.The white around the welds?  What can I do?   Plate is about 1" aluminum.  I have about 190 amps.  It took all she had to make those welds.  I tried different frequency.   All I care about are the welds, not the white around it.There are no black spots in the weld, so it was clean as it can get.  The only black is where I dunked the tungsten.  I have to keep a short arc because I needed all the heat I could get.I will get a close up of a few beads today before they pick them up.  All were welded flat.  I turned the piece so the beveled edges were up.DavidReal world weldin.  When I grow up I want to be a tig weldor.
Reply:I really like your tungsten holder!I will be stealing this idea. :-)JoeMiller 140 Autoset (2010)Miller Syncrowave 250 (1996)
Reply:Not enough amps for that job at all... I would hate risking my reputation by using the wrong tools for the job just so you can get a job out. But what the hell do I know, gotta pay the bills I guess.
Reply:Depends on how much of a bevel he had.HTP Invertig 201Lincoln Idealarc SP250Miller 180 AC StickBy farmall:They should have held the seagull closer to the work, squeezing evenly for best deposition.
Reply:On thick stuff like this with the machine giving the max output for penetration, why run such high AC Balance (35% EP)?  I would have dropped it down to at least down to 20% EP (probably even lower as long as the puddle was staying clean.)  That would direct the limited power more into melting the work, instead of heating your tungsten.  It makes a big difference.Also, some helium mixed into your shielding gas, or a pre-heating blast with a 300-400k BTU weed burner torch for about 10-20 or so seconds would have made the welding go a lot more quickly, I'll bet.Did you run into your machine's duty cycle limit?  I see according to the specs, an ArcMaster (if that's what you've got) is rated 30% duty cycle at the max 185 amps in TIG mode.If high strength in the as-welded joints were important, I would have used 5356 rather over 4043.  It's got more strength and ductility for welding 6061.  (Not supposed to be used for parts that operate at high service temperatures.)But, you got it done with what you had, so cheers for that.
Reply:+1 on the helium. If you ever ever ran a mix it welds VERY nice and is considerably hotter. You would have no issues welding with the correct mix.HTP Invertig 201Lincoln Idealarc SP250Miller 180 AC StickBy farmall:They should have held the seagull closer to the work, squeezing evenly for best deposition.
Reply:Originally Posted by jakeruOn thick stuff like this with the machine giving the max output for penetration, why run such high AC Balance (35% EP)?  I would have dropped it down to at least down to 20% EP (probably even lower as long as the puddle was staying clean.)  That would direct the limited power more into melting the work, instead of heating your tungsten.  It makes a big difference.I ran enough balance to keep the weld clean.  What ever it takes it what I use.  Anything below 25%  + does not work for me no matter how clean I keep the aluminum.Also, some helium mixed into your shielding gas, or a pre-heating blast with a 300-400k BTU weed burner torch for about 10-20 or so seconds would have made the welding go a lot more quickly, I'll bet.Did you run into your machine's duty cycle limit?  I see according to the specs, an ArcMaster (if that's what you've got) is rated 30% duty cycle at the max 185 amps in TIG mode.I have never run into the duty cycle.   Hoses get warm for the cooler and the welder will blow hot air out the exhaust.  In 5 years I have never seen the over temp light come on. That machine has done a LOT of work for me in both AC and DC.  I only use it for tigIf high strength in the as-welded joints were important, I would have used 5356 rather over 4043.  It's got more strength and ductility for welding 6061.  (Not supposed to be used for parts that operate at high service temperatures.)Look in the book.  For 6061 it says to use 4043.  I just found this on line.  5356 is an option.  http://www.lincolnelectric.com/en-us...um-detail.aspxBut, you got it done with what you had, so cheers for that.
Reply:Originally Posted by that'll_buff_outInteresting job David.Oh and nice 'tacks'I'm curious, welded horizontal orflipped up and done flat?I'm just a rookie but that's a lotof cleaning action with a wide etched area, no?I assume a ss brush and wipedown prior to get going or relyon the ac balance?
Reply:I'm glad you are taking my comments how they were intended: no ill will, just trying to help, or maybe just give you something to think about or mull over during your future projects.  I was surprised that the lincoln electric reference you linked indicates or implies that 4043 gives a higher as welded strength of the weld deposit than 5356 on 6061 parent metals.  This information is at odds with the following Alcotec aluminum filler rod selection chart:http://www.alcotec.com/us/en/support...on_Chart-2.pdf(Alcotec is a manufacturer of aluminum welding wire/rod, including some pretty exotic alloys by the way.)  Their chart is a little hard to read though, so below are the relevant portions:6061 parent metals welded with 4043:  "C" as-welded strength, "B" ductility6061 parent metals welded w/ 5356:  "B" as-welded strength, "A" ductilityIt seems odd to me that you need such high EP% to keep the puddle clear.  It makes me think *maybe* you have a problem with somewhat contaminated gas (loose fitting somewhere?) or maybe a suboptimal flow rate selected for the cup/collet you are using... or something.  (25 cfh is a LOT!  But then a #8 cup is pretty big too.  If I were using the #8 gas lens cup, I'd probably be using less argon flow, as little as 15 cfh.  Maybe you have turbulence from too much gas flow?)
Reply:Originally Posted by joebieI really like your tungsten holder!I will be stealing this idea. :-)