HELP - TIG aluminum T-joint

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I'm trying to build an aluminum tool tray with a middle divider. It is about 17" x 10". I started with welding the divider, but what a disaster. Obviously too much heat, too quick. It looked like a roller coaster by the time I was through.So, give me some tips besides "run hotter and quicker" because I'm old and slow. I am doing a lot better with TIG, but still not where I want to be.I'm guessing tack, allow to cool, tack, repeat, until I have several tacks and then run my bead.Other tips and suggestions?Burt _____________________Miller Syncrowave 250Millermatic 211Miller 375 Plasma Cutter Hobart Handler 12010FtDrillBit.com
Reply:Picts of your weld would help. Many times guys have real issues getting the bead started. It can help if you strike your arc on the filler and use that puddle to bridge the gap between the two right at the beginning vs trying to get a big puddle started and then start adding filler. With new students what usually happens when they try to simply form a puddle is that the upper plate with the thin edge melts away and now they have a bigger gap to try and bridge... Once you get the bead going things get easier for most guys. The only time they don't is when the guys are trying to weld too slow and cold and the material is heating up too much. Then everything goes to crap on them as soon as the whole edge reaches the melting point.Alum is all about heat control. If you can't control the heat and manage the puddle, you won't have any real luck doing alum. Hot and fast really is the way to go. You just have to learn to manage it. If you don't go fast and hot, the heat build up will kill you. As soon as the material reaches the melting point everything will want to go at once and you no longer have any control at all..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:Hey Doug.Thanks for the reply. Believe me, you don't want to see pictures of this! At least I don't want to show them.I've been practicing aluminum for several months now, and can usually do pretty good on flat beads, outside corners, etc. but seem to have all the problems you described on T-joints. I can usually tack ok, but then getting the puddle started is hard. Once I get it moving, it flows pretty good.I know my problem is too much heat, so need help on limiting the heat. Should I run short beads and allow to cool or should I be able to run the whole length if I move fast enough?Burt _____________________Miller Syncrowave 250Millermatic 211Miller 375 Plasma Cutter Hobart Handler 12010FtDrillBit.com
Reply:Welcome to sheet metal.You could sandwich the divider and sidewalls between plates to restrain. The other way I use is bend flanges on the divider. But like you said, skip welding and backstepping can help. What are your sheet thicknesses?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:Seeing the "mess" would help me understand why you are having trouble with the heat.In some cases it can help to do a short weld, then move somewhere else and do a weld there. 10" of bead should be easy to run in one shot heat wise unless you are doing something wrong, like taking too long to get the puddle started by having your amps too low. Even 17" should be doable, but most guys can't handle filler well enough to do a bead that long in one shot.I see this a lot with guys trying to learn alum. It tends to irritate them that I can run a bead almost effortlessly using the same machine setup they are and they are having so much trouble. In many cases I even crank the amps on the machine up higher to do the beads. That's because for 1/8" we usually set the machines to 150-165 amps so the students can simply floor the pedal to start the puddle and then back off. Because I have more experience and skill at heat control, setting the machine at 180 or 200 amps allows me to almost instantly get the alum to puddle and then I back off almost as fast and run the bead at lower amps using the pedal to manage the heat as I go. Most students want to try and creep up on the amps and take their time getting the puddle to form. That's not the way to do it. Mash that pedal down and get the puddle formed NOW!Even without seeing your bead I can pretty much envision what it probably looks like. The only other issue I occasionally see is guys using too long an arc length so they can see better. Instead, stick the tungsten out a bit more ( a gas lens really helps here) so you can see the arc length better and keep the tungsten in tighter. Keep in mind alum plumps up more than steel usually does, so you do need to be back a bit farther when doing alum than you do with steel or you dip the tungsten in the puddle..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:Hmmm... I wasn't thinking sheet metal Terry. I was thinking he was probably working with 1/8", so my comment was aimed more at that. Thinner stuff would be a bit different. A bent flange on the divider and a lap weld would be one option if it's thinner though that hadn't occurred to me since I was thinking thicker 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:If it is just a divider for a tool tray could you just weld a few inches of it? A nice bead along the whole joint looks nice but for a tool tray shouldn't be required.Airco Ac/Dc 300 HeliwelderMillerMatic 200 (stolen)Miller Maxstar 150STLMiller AEAD200LE (welding and generating power) Hobart MIG
Reply:The piece I used (read mangled and then bent with a hammer trying to straighten) was thinner than 1/8", more like 14 gauge. I forget the actual size since I got it out of a scrap bin. It is new material and I have successfully TIG welded a lot of it, even T-Joints on shorter pieces. I think it is just my learning curve because these pieces were much larger than my practice pieces. So larger means longer welding beads, equals more heat put into it, and consequently more distortion over a larger piece. I know that my bead got a lot bigger than I wanted, trying to catch the edges that were melting and pulling away. I have some 1/8" that I'm going to use for the bottom of "Tool Tray, the Sequel". I will try running hotter and faster, but maybe not the whole length at one time. As Terry suggested, I'll weld like it was sheet metal with skip welding and let it cool. It does not need to be a solid bead anyway for this project. Doug, I will post some pictures of it, good, bad, or ugly.Bending the divider and making a flange would be a good idea, but my home-made bender would not do this thick aluminum.I appreciate your help. Aluminum TIG is fun and a challenge! I have made a lot of progress over the last several months, consumming about 15 pounds of filler so far. Still a long way to go before I get to where I want to be.These guys that want to buy a TIG welder and start building roll cages and such crack me up. They just do not have an appreciation for how much hood time it takes to be proficient.Sorry, Squirmy. You must have posted while I was composing this post. You are right, see my comment about not doing a solid bead.Burt _____________________Miller Syncrowave 250Millermatic 211Miller 375 Plasma Cutter Hobart Handler 12010FtDrillBit.com
Reply:Don't feel bad you should have seen the mess i made playing with terry's dynasty 700 on a 1" Tee joint I never welded 1" thick aluminum but terry showed me it can be done by stepping forward doing the root stepping back doing the fillet rinse and repeatI didn't do well at it ...I would have to take my own advise of practice practice but it's to far to terry's shop and i don't think he will let me bring that 700 home with me to practice with Backed my CATMA over your CARMA oops clusmy me  What would SATAN do ?? Miller Trailblazer 302 AirPakMiller Digital Elite  Optrel Welding HatArcair K4000Suitcase 12RC / 12 VSHypertherm PM-45Rage 3 sawRusty old Truck
Reply:Things are also a lot different when welding in a "box". It's easy to weld joints when there is nothing in the way. It's not so easy when all of a sudden you have to reach inside and weld at the bottom of something. I helped a student weld up an alum bot to make lead shot with a couple of years back. the inside beads were giving him fits because as soon as he stuck both hands in the box he couldn't see easily any longer, or he had to manipulalte the torch in an awkward way to reach where he needed to. It worked better when he left the front off the "box" and welded the inside 1st, then went back and welded the front on... Order of operations sometimes makes a big difference..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:I was doing the divider in the middle first so it was just on the flat bottom. So I did not have the sides blocking my view, but I considered if the sides were already on they might constrain it from warping.As my 4 year old grandson says, "it's a conumdrum".Burt _____________________Miller Syncrowave 250Millermatic 211Miller 375 Plasma Cutter Hobart Handler 12010FtDrillBit.com
Reply:I know you want tig advise. What about rivets? Flange each end, rivet them and call it good. Easy to reconfigure.
Reply:Rivets? That's cheating! . . . just kidding.Good point, and probably the better alternative. But I've been trying to learn how to TIG for months, so I really would like to have some practical results. I know I should be able to do it, just need more practice. But thanks for the idea in case I burn up all my material.Kind of reminds me of an old man I used to know, that traded cows for living. He was always being asked to teach young guys how to make money trading cows.His answer was to take $50,000 of your own money and start buying and selling cows. He said when you lose that, then go borrow $50,000 and you'll know how to trade.So when I burn up all this material, then I'll go buy some more and maybe I'll know how to TIG it.Burt _____________________Miller Syncrowave 250Millermatic 211Miller 375 Plasma Cutter Hobart Handler 12010FtDrillBit.com
Reply:Originally Posted by killdozerd11Don't feel bad you should have seen the mess i made playing with terry's dynasty 700 on a 1" Tee joint I never welded 1" thick aluminum but terry showed me it can be done by stepping forward doing the root stepping back doing the fillet rinse and repeatI didn't do well at it ...I would have to take my own advise of practice practice but it's to far to terry's shop and i don't think he will let me bring that 700 home with me to practice with
Reply:Originally Posted by wb4rtThese guys that want to buy a TIG welder and start building roll cages and such crack me up. They just do not have an appreciation for how much hood time it takes to be proficient.
Reply:Tool Tray, the Sequel!OK, took everyone's advice (Thanks!), and used 1/8" for the new bottom and new divider. It worked much better. Outside edges are still the 14 gauage (?). I had a little bit of pull on the bottom, but was able to align it with the sides and get it back flat. Tacked it up nicely. Then I was able to get the puddle started and move "fast and hot" or at least faster and hotter. Still not where I want to be on appearance, but acceptable for me. I plan to finish the outside beads in the morning.Any instructions, comments, etc. are appreciated.Burt _____________________Miller Syncrowave 250Millermatic 211Miller 375 Plasma Cutter Hobart Handler 12010FtDrillBit.com
Reply:Burt _____________________Miller Syncrowave 250Millermatic 211Miller 375 Plasma Cutter Hobart Handler 12010FtDrillBit.com
Reply:Looks good enough to hold - for sure! Rick V 1 Airco Heliwelder 3A/DDR3 CTC 70/90 amp Stick/Tig Inverters in Parallel1 Lincoln MIG PAK 151 Oxy-Acet
Reply:Finished the outside beads. Again, I know I should be able to do better, but this will work for me. I can still see where the tacks were, should I have ground them before welding? That caused part of my inconsistency, but still need practice.  Any comments or suggestions or instructions?Burt _____________________Miller Syncrowave 250Millermatic 211Miller 375 Plasma Cutter Hobart Handler 12010FtDrillBit.com
Reply:You could, but usually I just melt them in as I go by and don't add as much filler so the beads stay consistent.The pict is to vague to make more than general comments, but I can see that the edges are a bit inconsistent like you mentioned.  Practice, and practice doing long beads, not 3" or 4" ones will solve that. It's a typical complaint I hear occasionally about students. They can make nice beads over a short length, but they can't do it over any longer lengths because they simply never had the opportunity to do so. It can be hard to justify the practice materials to do long welds. Many times the only opportunity to do this is on real projects.What little I can see up front looks pretty good. The section about 1/4 of the way in to maybe half way from the left looks pretty consistent and even with a nice pattern to the dips. That tells me you CAN do this. You just need to keep working on the little things.Now the biggie... What's the inside corner look like? The last pict in post 16 and the one in post 17, it looks like you set up your outside corners so the inside edges just touched and you have a V to fill in the corner. If so Good. The real question is if you were able to fill all the way down to the root and get just a tiny bit of melt thru on the inside to break down those inside edges. That would tell me more about your skill than what the top edge looked like. I'm going to guess that if you got all the way thru, it looks erratic and inconsistent, somewhat similar to the top with occasional spots where you didn't go all the way thru. It wouldn't surprise me if the places where you didn't go all the way thru were around where you had the tacks. That would be fairly consistent with what I see students at your level doing. Those that need to work more on their joints would show little to know melt thru what so ever and they need to spend a bit more time working on getting full penetration before they worry too much about what the top looks like. Most times it's due to the fact they are scarred they will go too hot and make a mess. That happens and if you aren't having that issue occasionally while learning outside corners, then chances are you aren't learning to go hot enough..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:Doug,Thanks for comments and help.Here are a couple of pictures of the inside corners. Again, not completely consistent, but some penetration. Let me know what you think.Burt _____________________Miller Syncrowave 250Millermatic 211Miller 375 Plasma Cutter Hobart Handler 12010FtDrillBit.com
Reply:1st pict was pretty much what I expected. 2nd pict looks like you were not getting any penetration at all ( or if you were it's so small I can't see it in that pict).In #1 it looks like you are tending to favor one side or another. I'd guess that has to do most likely with torch angle or the way you have your torch hand positioned. Looks like you had a tendency to favor the side more than the bottom. Assuming this was upside down when welded, that would make the side the "lower" edge. That sort of tells me you could stand to toss a bit more heat at the "upper" ( bottom of the tray) piece and that you really aren't getting the root in well. You are real close in pict #1. You've got the heat, but it's not in the right place all the time. Open corner joints in alum are quite tough. You need enough heat to break everything down, but not so much that you blow thru or have excessive reinforcement. It takes a lot of practice to do this. Add to the fact that if this was welded the way I think it was, then technically you are doing a horizontal  weld vs a flat weld and you get to fight gravity at the same time to a certain extent.I can think of several things that might help some what. If I was doing this it would be a toss up 3/32" or 1/8" 1.5% or 2% lantanated ground to a point. The 3/32" would give me a bit tighter arc, but it won't hold up as well to the amps I'd like to run. 1/8" would hold up better, but the arc would be a bit larger and I wouldn't have as tight of control as I would with the smaller tungsten. I'd have to run both and pick my favorite on that particular day. filler size would also play a part. Bigger filler chills the puddle more than smaller filler. This can help or hurt you depending on your personal way of welding. Going smaller would allow a bit more heat, but you might be able to jam bigger filler deeper in the puddle... I'd start with 3/32" filler. I'd have to look if I have any 1/16" filler on hand. Issue I have with 1/16" filler and newer students is if they cant the torch too much, the filler never makes it to the puddle before it melts off.I know Terry is usually a fan of big filler. I'd be curious to hear what his thoughts are on this from the perspective of teaching a newer welder alum tig and what tungsten and settings he'd use. His Dynasty's would allow him to run 3/32" with no problems and he could also crank up the Hz to gain an advantage we don't have using the older Syncrowaves..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