Tig aluminum

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I've finished my stainless tig pipe after three tries and passed the visual and now its out for xray.  At this point I'm working on tigging aluminum plate using a miller 351 synchro with a water cooled fixed torch with 5/32 pure tungsten with %100 argon shield at 60cfh and amps at 175 and post flow at 9 seconds and arc control at 30 and filler is 3/32.  My difficulty is in working with the filler to get it to melt into the bottom and side plate of the practice T joint that I'm doing in the horizontal position.  I've made sure the tungsten is clean and blunt and I have it between 1/16 to 1/8 off the plate surface at 90 to the root.  Some times I have luck with poking the filler into the "puddle" while other times its a no go.  I've made sure to watch where the arc is going and once all of the oxidation that could not be removed with a brush is gone I poke and some times it blends in while others it doesn't.  I've tried to set up a pattern for weave torch and jab filler but aluminum just doesn't move or react like steel does and its driving me nuts.
Reply:Thats a pretty large tungsten I usually use 3/32 thoriated but thats me. Seems like a lot of gas flow as well, I usually set mine around 20cfh and seems to work fine. Make sure that you are holding a tight arc length and focus on the tungsten on the puddle. Make sure your pushing the filler at a reletively flat angle (thats that I like to do) and you need to kind of "force" it in. Show some pictures so we know were you are at.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:Oh are you saying the ac balance is at 30? Try it at around 70...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:IMO 60 cfm is going to hurt you with welding aluminum. Aluminum isn't like stainless where more shielding is better, in reality the lower the better (like 15 cfm at the most). When I have gone higher (like 20+ cfm) the arc gets wild and starts popping back on your tungsten.And #1 with aluminum is get that oxide layer off, take a clean brand new SS scratch brush and brush off any oxides till it gives you resistence.
Reply:Yeah highest I go is 20 cfm and 3/32 pure tung. I start with the upper plate first and get a puddle going and dip the filler to make a small knob, then move to the lower plate and do pretty much the same then join the two knobs and start welding along the joint.
Reply:IMO 5/32 is too big for 175 A, I would use 1/8. Gas flow doesn't need to be 60 cfh. I know there's lots of discussion about low vs high flow rates, and you need to find what works best in your situation, but I seldom run less than 25-30 cfh with a wp-18 torch. You really don't want to weave much, get your torch angle so you're melting both sides of the joint before adding filler. You didn't say what thicknesses of plate you're welding...that will make a difference on the advice given. If it's pretty thick, say 3/8 or so, the 5/32 tungsten might be OK, you may just need more amps.As others have said, make sure to clean all surfaces of the weld joint with a clean SS brush before tacking. I agree that you should try setting the balance at about 70, that will put more heat into the weld.+1 on pics.
Reply:Not my call on the size of the tungsten nor the gas flow as it is what I was told to use / set it at though I will attempt to get that free'd up.  I can't take pictures of the work piece itself due to federal military and company restrictions on the possession of camera's on company property.  I do have some pieces I took in with me that I will show but the difference between them an the practice piece is night and day and makes me wonder if it has something to do with the material.
Reply:Anyone who knows has welded alum before knows that 60 cfh is just waaaay overkill (hell for any TIG welding) thats like a air nozzle....I really bothers me when people say "I can't help this because the instructor, etc wont let me change it" like what the eff is going on with your instructor? lol
Reply:WOW i agree 60CFH maybe 30 max have done 1/2 " alum an only used 20 but if the boss said so then its his bux matbe use a gasslens to help cut back on swirlidealarc 250/250 ac-dc tigidealarc 250/250 ac-dc tig #2 used for sticklincoln sp100hh125dual arbor grinder polisher30 yrs of hand tools52 pitch blocks 6p-26prake gauge -pitch gaugeG&D prop repair 918-207-6938Hulbert,okla 74441
Reply:Big65,As has already been mentioned, your settings are all way off.  No way are you going to be successful learning to tig weld aluminum with those settings.Are you in the "Apprentice School", or is NN now running a different training program?I have a "little experience" welding aluminum on the Syncrowaves so here are a few of my recommended settings.Balance    Set at 70-80 assuming you're cleaning the aluminum pre weld.Gas          Set at 20 CFH.  If bead show any porosity, increase in 5 CFH increments.Tungsten   1/8" for 175A.  I'm assuming that they dictate the use of pure.  For "out of the shop work", if you like a balled tip, you might want to try the Zirconated.Filler          3/32" but takes practice to keep it in the covering gas and not melt it before you get it in the puddle.  If you go up in A (even a little) the 1/8" may work better for you.You didn't mention the thickness of the material you're welding, but you'll find that generally it's best to use more amps to get a "quick puddle" and then back off on the pedal as the heat starts to build in the material.  Aluminum likes to be welded hot and fast.  Hot and fast also helps to reduce the HAZ.Not at all a fan of the use of Thoriated tungsten for AC welding on a transformer based machine.  Every time I've tried it, the tungsten forms a series of small ba11s around the tip, which tend to blow off and end up in the puddle.  I do use the thoriated for steel/SS.Syncro 250 DX Dynasty 200 DXMM 251 w/30A SG XMT 304 w/714 Feeder & Optima PulserHH187Dialarc 250 AC/DCHypertherm PM 1250Smith, Harris, Victor O/ASmith and Thermco Gas MixersAccess to a full fab shop with CNC Plasma, Water Jet, etc.
Reply:Hi Big65.Need thickness, and sizes of plate. Alloy would be nice too. What is your filler? Are you doing any preheat at all?Perhaps your instructors are trying to pull a fast one on you?
Reply:Ask to see the Techniqe Sheet (or WPS, or whatever they call it there). It should tell you the allowable settings for gas, amperage, tungsten size, filler size, etc. You have the right to use whatever settings are listed on the sheet. I've never taken a certification test where the technique sheet wasn't available.
Reply:The settings quoted don't make much sense.  I would think that 175 amps with only 30% EN would put barely enough heat into the work to form a puddle on 1/8" material, leaving very little excess heat to melt the filler. Most of the energy from the arc is wasted heating the tungsten, which might explain the enormous flow rate for the shielding gas, and the oversize tungsten.Assuming that the material is somewhere in the ball park of 1/8": 150 amps max, ~70% EN, 15-20CFM of argon, 3/32" pure (or alloyed) tungsten, and 1/6" or 3/32" filler would be about right; putting in the neighborhood of 100% more energy into the work than the settings quoted in the initial post.  The settings quoted seem like they were intentionally set up wrong unless the materials being welded are thin (1/6") and filthy (or anodized), necessitating additional cleaning action from the arc.  The cleaning stripe must be huge!
Reply:Thats why we told him to set the balance at 70....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:Only thing I see that might not have been already addressed is that the size of the tungsten could be partially why you are having issues getting both pieces to flow together.  With that large of an electrode and relatively low amps you are winding up with an arc with very low energy density, which will make it hard to have a stable and controllable arc.Going to a smaller electrode with the same amperage will make the arc much more stable and focused and should allow you to get the two pieces to flow together.I dont know who is making you use such a stupid large tungsten, but I normally run 3/32 to ~220A AC at 75-85% EN with no issues.  1/8" thoriated will get me to 300A easy.Have we all gone mad?
Reply:Ok here is the sheet I was given for the testing that will be done.2G, 3G, & 4GGTAW (806)Base metal alum 5456 3/8 plate ( what I'm using right now looks to be about 1/4 to 5/16)Filler metal ER5356Backing strapTungsten type & size 5/32 pure (ewp)cup size 7 - 10Gas %75 helium + %25 argon @ 35 - 80 cfh (60)preheat 60F min,; 500F max ( optional)interpass NAWelding parameters Filler Metal ER5356 or ER5556 of AWS A5.10 [22B]Amps  1/8 160 - 200 amps (185) 2G-4G (175) 3GRoot Opening1/2 2G, 3G, 9/16 4GMonday when I go in I will talk with the other instructor and look at making changes to the shielding gas flow rate, the instructor was able to run a bead but then I don't have 20+ years of experience either and I couldn't see what he was doing very well as he is a large guy and the training booth is small.I have a little ways to go  before I can get into the apprenticeship school, what I'm in right now is a basic hands on school and I'm kicking myself for not applying before I finished technical school welding last year.  I took 5 months off after I graduated and focused on family and ended up forgetting allot it seems and its been a relearning process ever since but at least I have done in 4 months what took me a year to do.I imagine that the size requirement has more to do with the testing process that the Navy requires than what will be used out in the yard and in the shops so in other words its government regulations.I'll post pics of the scrap pieces that I took in and brought home to take a pic of them here and not there.Welding Supervisor Department of Corrections.
Reply:Big65,The fact that you're using a 75%He/25%Argon mix explains somewhat the high flow rates.  Helium is lighter than air and therefore rises (Argon is heavier than air and settles).  As a result the flow rates have to be higher.  With that said, I'd recommend a flow rate in the 50 or so CFH range.Using the He/Ar mix also means that you can get by with less amps.  That mix will yield a hotter arc than straight argon.  This (somewhat) also explains the larger tungsten.  Still think you're going to be close to the 200A range to weld 3/8" aluminum.You didn't mention balance settings in the info you provided.  I'd still recommend setting the balance around the 70% range.  The higher you go in balance (with Miller machines) the more time the machine stays in DC- , which puts more heat into the workpiece rather than the tungsten.  Reducing the balance setting increases the DC+ which gives more cleaning effect, but puts more heat into the tungsten and less heat into the workpiece.Wish the timing were different.  I'd suggest you drive up here and we'd set you up with the same gas/material/etc and hone in on the amps/balance.  I'm about an hour and twenty minutes from the yard. In fact, if you can get away tomorrow afternoon, drop me a PM in the AM along with a phone # and I'll give you a call.Syncro 250 DX Dynasty 200 DXMM 251 w/30A SG XMT 304 w/714 Feeder & Optima PulserHH187Dialarc 250 AC/DCHypertherm PM 1250Smith, Harris, Victor O/ASmith and Thermco Gas MixersAccess to a full fab shop with CNC Plasma, Water Jet, etc.
Reply:2G, 3G, & 4G are different animals than fillet welds. It is harder to get the root to fuse at the amperages you are using without dwelling there. The plate alum will conduct the heat right away from the weld zone. Why not just crank it up to maximum?The rest of the weld parameters seem workable to me. Earlier you mentioned 100% argon, so that threw me off. Sundown is right about the helium/argon needing more flow, so that fits in.I would go for bigger filler too. I would go nuts if I had to use 3/32 dia. on 1/4-5/16 plate.
Reply:so I went in this morning and started making some changes to the gas flow and the arc control then I did some tapering on the tungsten to take it down to 3/32 diameter and later adjusted the heat.  Things got better but still needed work and after the second instructor came in to advise on some corrections and further adjustment on the machine I turned things around.  Amps went from 175 to 185, cfh was dropped to 30 then moved to 40 after being at 60, arc control was set to 35 after adjusting around a bit, work angle was adjusted slightly and all is good.Welding Supervisor Department of Corrections.
Reply:I assume by the tungsten size your using a WP-18 torch?  I only use that size when the material reaches 3/8 and up since the weld prep will be getting large in size and you need more heat area.....20 cfh with argon should be more than enough with  that torch especially if your using a gas lens..I'm old school and even though I use zirconiated  and other newer tungstens  I still like pure balled up....  Miller Dynasty 350Twenty Six HammersThree Crow BarsBig Rock
Reply:Drawing a blank at the moment ( mango margaritas will do that to ya ) but I believe that that is the correct torch.  As in another thread gas flow for testing along with all other settings is set by Navy standards for testing and I have a limited range to work with and I took mine down to 50 and worked the heat from 175 to 185 for horizontal vertical and overhead using 75/25 helium/argon mix.  I still ended up with soot but everything was brushed down after each bead leaving me to deal with a little residue on the start of each bead.Welding Supervisor Department of Corrections.
Reply:Ok, I am just going to say it. 50cfh is just too much and really a huge waste of gas, almost criminal. Now maybe the cost is all covered by the government, you might just be screwing up your own weld by drawing air in behind your cover gas via a venturi effect.Only way I could see justifying that much gas is with a giant orafice in you cup. What is it like 1" or bigger? But alum just does not need it.Also you have a Sync 351. Just crank that puppy right up to max(300 amps?) and quit messing around. Before any WPS can be used you need to make sure your equipment is capable of the task.You seem to know where you want to be with this. You might be better served by going to the Miller website and scour for the correct parameters. Your machine is a Miller.Perhaps your instructor needs to bring in a consultant to rework his parameters and lessons.Weld like a "WELDOR", not a wel-"DERR" MillerDynasty700DX,Dynasty350DX4ea,Dynasty200DX,Li  ncolnSW200-2ea.,MillerMatic350P,MillerMatic200w/spoolgun,MKCobraMig260,Lincoln SP-170T,PlasmaCam/Hypertherm1250,HFProTig2ea,MigMax1ea.
Reply:Sundown offered to let you visit his shop and show you how it is really done right. You will learn in 5 minutes what it may take you 5 months to learn from your genius instructor. Maybe your instructor is playing a joke on you.Biggest hurdle is to see it done, then have someone immediately MAKE you do it. Then show you AGAIN, and MAKE you do it. Ect,Ect,Ect. I breath right down my rookies back while I watch thru my hood and YELL at him while he is laying the rod.Good luck.Weld like a "WELDOR", not a wel-"DERR" MillerDynasty700DX,Dynasty350DX4ea,Dynasty200DX,Li  ncolnSW200-2ea.,MillerMatic350P,MillerMatic200w/spoolgun,MKCobraMig260,Lincoln SP-170T,PlasmaCam/Hypertherm1250,HFProTig2ea,MigMax1ea.
Reply:Originally Posted by shovelonI breath right down my rookies back while I watch thru my hood and YELL at him while he is laying the rod.
Reply:Originally Posted by Rick VBrrrr... reading this, I can almsot feel you breathing down my neck!I can just see it, all quiet in the shop, guy TIG welding all by himself for awhile, boss sneaks up behind and yells "YOUR DOING IT WRONG!"
Reply:Originally Posted by Big65moparDrawing a blank at the moment ( mango margaritas will do that to ya ) but I believe that that is the correct torch.  As in another thread gas flow for testing along with all other settings is set by Navy standards for testing and I have a limited range to work with and I took mine down to 50 and worked the heat from 175 to 185 for horizontal vertical and overhead using 75/25 helium/argon mix.  I still ended up with soot but everything was brushed down after each bead leaving me to deal with a little residue on the start of each bead.
Reply:Originally Posted by VPTI can just see it, all quiet in the shop, guy TIG welding all by himself for awhile, boss sneaks up behind and yells "YOUR DOING IT WRONG!"
Reply:Originally Posted by shovelonSundown offered to let you visit his shop and show you how it is really done right. You will learn in 5 minutes what it may take you 5 months to learn from your genius instructor. Maybe your instructor is playing a joke on you.Biggest hurdle is to see it done, then have someone immediately MAKE you do it. Then show you AGAIN, and MAKE you do it. Ect,Ect,Ect. I breath right down my rookies back while I watch thru my hood and YELL at him while he is laying the rod.Good luck.
Reply:Originally Posted by SundownIIIBig65,The fact that you're using a 75%He/25%Argon mix explains somewhat the high flow rates.  Helium is lighter than air and therefore rises (Argon is heavier than air and settles).  As a result the flow rates have to be higher.  With that said, I'd recommend a flow rate in the 50 or so CFH range.Using the He/Ar mix also means that you can get by with less amps.  That mix will yield a hotter arc than straight argon.  This (somewhat) also explains the larger tungsten.  Still think you're going to be close to the 200A range to weld 3/8" aluminum.You didn't mention balance settings in the info you provided.  I'd still recommend setting the balance around the 70% range.  The higher you go in balance (with Miller machines) the more time the machine stays in DC- , which puts more heat into the workpiece rather than the tungsten.  Reducing the balance setting increases the DC+ which gives more cleaning effect, but puts more heat into the tungsten and less heat into the workpiece.Wish the timing were different.  I'd suggest you drive up here and we'd set you up with the same gas/material/etc and hone in on the amps/balance.  I'm about an hour and twenty minutes from the yard. In fact, if you can get away tomorrow afternoon, drop me a PM in the AM along with a phone # and I'll give you a call.
Reply:I went back and had to retake the vertical and overhead tests.  Despite my arguments I was not allowed to change the settings outside of the parameters set forth by the Navy and I still had issues with the overhead but the vertical looked good  on the grind and visual inspection.Welding Supervisor Department of Corrections.
Reply:Originally Posted by Welding_SwedeIf you tried that in my welding booth you'd get a chipping hammer between the eyes. Behavior like that doesn't make you a good teacher... just makes you an a$$hole.
Reply:Originally Posted by Big65moparI went back and had to retake the vertical and overhead tests.  Despite my arguments I was not allowed to change the settings outside of the parameters set forth by the Navy and I still had issues with the overhead but the vertical looked good  on the grind and visual inspection.
Reply:Going back again in the morning, passed the vertical but the overhead had porosity again.Welding Supervisor Department of Corrections.
Reply:Heat was bad today but the humidity really killed it for me on top of a torch problem and trying to work out a position to get into to do the right side root.  I'm still getting black soot but not like I was before and now one of the instructors is telling me that my position to the overhead plate is wrong.  I'm standing just off to the side of the plate and above the weld area like I'm doing a horizontal weld but I'm slightly above but still facing it and pulling the torch right to left.  He walked into my booth telling me it was all wrong only after I showed him that I was still pulling the torch towards me just not head on while I was resting my hand in a general position to give him an idea.  I found it difficult to hold my hand out in front of me and pull the torch towards me as if I was holding my arm out palm down and not have it rise up and fall down due in part to my respiration.  Every time I turn around I'm getting told what I'm doing is wrong and I had always been told prior to this and after this that I need to do what works for me and frankly these two are making me go nuts trying to figure out what I need to do in order to get this done right.Welding Supervisor Department of Corrections.
Reply:Porosity in the beads so its back to the school Monday and try again.  It doesn't help that the humidity has been %70 - %95 and the air temp has been 88F - 100F inside the building from 7am forward.Welding Supervisor Department of Corrections.
Reply:are you using a water cooled torch ? are you preheating the plate ? that high of humidity its gonna be a bear, try this if u see major porosity in the start side of the weld shut your water cooler down after u finish a bead unless your going to start the next one right away, next thing if your doing test plates and arent sure of your wire brush get a new one who cares there 3$ max, brush the plate one direction only from one end to the other lift brush start on the other end again and go all the way to the end and repeat cleanliness is your friendfigure out whats comfortable to you but stay in the path of the bead where you can see both sides of the plate not off to one edge looking up i use vice grips on plates to extend them to hold my arm steady it works for me so ya , i try to keep 3 points of contact on my body to something at all times while doing test plates but remember 4 dont hurt either if have to make smaller interpass beads , it will help with the porosity , i hope something i say helps if not just ignore me lolI forgot how to change this.
Reply:Using a thermal arc 300cc/cv running it at 170 amps with 60/20 on the pen and clean.  Plate was cooked over night in an oven but fit up was not on the money ( not my work, my fit ups are always %100 ).  Second day I cooked the plate with a map torch, brush is a stainless steel dedicated brush used only on aluminum testing.  Difficulties come from a combination of the jig that holds the plate and the table the jig is mounted to that limits movement in some ways.  It's a pain and I have used clamp on arm rests to the best of my ability and have modified the jig by tacking on a flat bar to use as a guide but it is overhead and aluminum and not the easiest thing to do. Attached ImagesWelding Supervisor Department of Corrections.
Reply:Oh yea, the amp range is working fine and burning in good, cfh of 55 on 75/25 helium argon, 5/32 pure tungsten ground to 3/32, #8 cup, new torch and parts and all specs for the test are per Navy requirements.Welding Supervisor Department of Corrections.
Reply:it will come with time i just certed to 15.1 this past week vert and overhead for a job im doin startin in a few weeks , btw it was a turn machine on do some random settings and the longest part was waitin on interpass temps to drop , passed first shot , it all comes with practice, like i said try smaller beads dont just flood the pool with rod , keep the rod tight so u dont introduce hydrogen and keep trying, keep in your mind pool size and relax just go with the flow , can you switch the direction of the plate ie turn it 90 degrees ?I forgot how to change this.
Reply:Nope on turning the plate, the jig has an arm that comes down on the left and right and once the shims and wedges are hammered in it forces the plate to stay straight through the whole process.  I did go with smaller beads but I had problems with the filler sticking to the plate and had to raise it a bit.  The filler is still causing black soot every time I dip it but not as bad as before so I think I'm going to up the cfh to try and flood the weld area more.Welding Supervisor Department of Corrections.
Reply:Well the instructors washed me out of the aluminum process and told me to come back in a few months with more experience....kind of hard to do that when you don't have the qualifications to work on aluminum.  Still can't get away from the porosity in the overhead regardless of what position I'm in.  I've asked to be shown the process in action but all that I get shown is mimicry at best with the instructor(s) standing in front of me posing and stating it needs to be done this way.Welding Supervisor Department of Corrections.
Reply:That sucks sorry. Are you still working for the company or was that a break out and your done ?I forgot how to change this.
Reply:That's pretty harsh. Even more so because the procedure they gave you is obviously flawed.Mr. Sundown offered to tutor you, he has the skills. Give him a shout.Weld like a "WELDOR", not a wel-"DERR" MillerDynasty700DX,Dynasty350DX4ea,Dynasty200DX,Li  ncolnSW200-2ea.,MillerMatic350P,MillerMatic200w/spoolgun,MKCobraMig260,Lincoln SP-170T,PlasmaCam/Hypertherm1250,HFProTig2ea,MigMax1ea.
Reply:Biggest problem is that he is nearly 3 hours from my house and if the hrbt and 64 is jacked up like it usually is that will add another hour + onto the travel time.Welding Supervisor Department of Corrections.
Reply:Originally Posted by LawsonWeldingLLCThat sucks sorry. Are you still working for the company or was that a break out and your done ?
Reply:Monday I plan to file a grievance with the school concerning the cfh requirements for the test, there's just to many people and support lines that are contradicting the cfh requirements for the test.Welding Supervisor Department of Corrections.
Reply:Originally Posted by Big65moparMonday I plan to file a grievance with the school concerning the cfh requirements for the test, there's just to many people and support lines that are contradicting the cfh requirements for the test.
Reply:Gonna be a while before I get my hands on my own box until I get some overtime in  during the next few months.Welding Supervisor Department of Corrections.