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Hello,I've been trying to imagine various ways of accomplishing this task. I've been trying to make a corner weld with my TIG for a little while with no solid success. I've joined metal for the first time a few days ago using an inside corner method, but I've been doing some reading and many say that the proper way to make a corner joint is to weld it from the outside.I have three theories in my mind. Bending the metal into a square form, tacking inside the joint then going outside, and somehow holding the aluminum in place while I weld. I hope I am being clear in my descriptions.Is it appropriate to tack the welds on the inside and then go outside or would that hurt the strength of the weld? If not, how does someone keep aluminum in this sort of corner that is pointing at you? I am working with 1/8th thick sheet metal.I am trying to make a box to be simple.Here are some examples of my current attempts at corner welds.http://yfrog.com/0dimg2010pjxThanks in advance.Miller 330 a/bp water cooledI believe in gun control, I hold my gun with two hands. If you want to know why, click here.Buy American or bye America.
Reply:From your pics it seems your running to hot and need more practice. I know we have people coming here and ask for advice on how to improve their welds but most improvements come from just spending time under the hood. Have you kept track of your hours? If you have more then 100 hours of practice time and are having trouble I can see you wanting some help but if not then get busy and get some time in. Maybe you should also practice doing some open root butt welds which would be very similar to your outside corner.
Reply:#1 put the pieces corner to corner.#2 use filler. I prefer 3/32.My name's not Jim....
Reply:To me it looks like you have a long ways to go learning heat control before you move to an outside corner. I'd also set the two pieces so that you have a small "V" at the corner and only the inside edges are touching and then fill.Alum is all about heat and puddle control. The only way to get that is lots of hood time. If you can control the puddle with steel easily, alum will come quickly once you work out the idiosyncrasies of what the alum puddle looks like and how it acts. If you skipped steel or didn't spend much time with it, you will have that much more trouble with alum..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 pinjas,I use a piece of 1/8" steel angle inside of the corner to absorb some heat & have a bit more control of the puddle. I just cut the size I need for the particular length. Here's a couple pics of how I do it......works quite well for either TIG or O/A.Denny Attached ImagesComplete Welding/Machine/Fab. ShopMobile UnitFinally retired*Moderator*"A man's word is his honor...without honor there is nothing.""Words are like bullets.... Once they leave your muzzle, you cannot get them back."
Reply:If you are making a box, I would put the joint in the middle of the straight (not in the corner) for a more symetrical look. Also, clean the metal with sand paper, ss wire brush, etc. to get rid of the contaminants from the manufacturing process.Millermatic 200Hobart Handler 120Victor O/A & Ramco BandsawLincoln 225 ACSnapOn AD HoodMiller XMT304/22AHypertherm Powermax 1650 G3Lincoln Idealarc DC600 w/Extreme 12 VSMiller Digital Elite "Joker"
Reply:Originally Posted by RaptorDunerIf you are making a box, I would put the joint in the middle of the straight (not in the corner) for a more symetrical look. Also, clean the metal with sand paper, ss wire brush, etc. to get rid of the contaminants from the manufacturing process.
Reply:Aluminum nearly always needs filler.Don't put the cart before the horse.Learn to control the puddle in the flat position before you try aluminum corners.Outside corners generally require about 10-20% less amps than the inside corners.Practice trying to obtain the "nearly perfect" tig bead with filler on plate before you move to corner welds.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:Although I am certainly not the most expert person on this board about this, I am working on a project involving 1/16" aluminum outside corners and am currently doing a lot of studying, testing, experimenting, and learning on aluminum corner welds. You can see attached a die (cube) I made as a test / not too serious project. It is a 1.5" x 1.5" x 1.5" box made from 1/16" aluminum. I also attached some practice welds I made on scrap pieces to dial in my setup and technique a bit, before I welded the cube.I found the techniques illustrated in this video by Jody Collier for welding a 1/16" aluminum box very helpful - it might be kind of an eye opener for you:http://www.weldingtipsandtricks.com/...g-project.htmlI have had both good, as well as bad results with the fusion (no filler rod) tack welds on aluminum. The best thing about it is you can use one hand to hold the pieces in position (IE: you can bend them tightly together in the spot you are tacking, if they are not completely straight), while the other hand holds the TIG torch. It is still helpful to clamp one or more work pieces to some angle, if you can. But it is also what I am getting the most "hit and miss" results with, and the misses will cause holes to be blown in your material. It would probably be easier with thicker material. When you don't blow through holes, and when the tacks hold and don't crack, the technique can be valuable for small, precision pieces, or bent, curved pieces that are hard to clamp down.When welding, it doesn't take much filler metal on an open outside corner weld, just a little. You can just weld your bead right through the tack welds.I need to weld curved edges to bent surfaces, which makes it hard to support with the angle, so that's why I'm trying to fine tune the tack welding technique so much.PS - I would think you could tack the insides of the corner, and weld it from the outside, but it would require you reposition the piece, it sounds like it may be harder way. If you are just learning, I think inside corner / fillet welds are the hardest. You'll need to hold a very tight arc and do what you can to "stiffen" the arc, to focus the heat on the inside edge.Pinjas, looking at your pictures, it looks like your welds are getting oxidied. Practice running some beads over a flat sheet. You need to get your gas shielding working right first. Pay attention to proper gas flow rate, not too much tungsten stick-out, and not too much arc length. You should be looking for shinier beads. Give your aluminum a quick stainless scratch brushing before welding. Attached Images
Reply:Originally Posted by yorkiepapHey pinjas,I use a piece of 1/8" steel angle inside of the corner to absorb some heat & have a bit more control of the puddle. I just cut the size I need for the particular length. Here's a couple pics of how I do it......works quite well for either TIG or O/A.Denny
Reply:Originally Posted by dave powelsonGood example of what William McCormick was describing aschill bars in thread below this one: TIG Aluminum FNG - Contaminated filler rod problem? http://weldingweb.com/vbb/showthread.php?t=42902......now that thread is locked, following discussion of chill bars!
Reply:While billy may be able to produce some good looking welds, I must point out that his "method" of welding aluminum is way out there in left field and totally unnessecary. Your a beginner, so PLEASE stick to the proven basics. Trying to lift the torch between each dab is only going to cause you more problems and hinder your learning curve. Switching to a smaller filler is also going to do more harm than good. Like I pointed out in that last thread, a larger filler is going to be much easier for a newbie to learn on. Nice, straight, steady motion with the torch and 3/32 filler is going to help you learn the basics much faster and will enable you to branch off to try whatever misguided methods your heart desires.Also, he is correct in pointing out that a chill block can be helpful in some situations. However I think I proved that it is by no means needed to get a sound weld. Angle iron inside of the joint is helpful for fitup and as a heat sink but I would suggest using thick aluminum or stainless angle. Using steel you are likely to pick up contaminates that will pull through to your weld puddle.And whoever suggested using sandpaper to clean aluminum clearly has no idea what they are talking about. Cleaning it with sandpaper is going to be about as helpful as cleaning it with a brick.As far as advice for tacking an outside corner joint together goes, this is how I like to do it. If the pieces are small enough to manage, I will lay one flat on the table. I take the other and stand it on edge on top of the other piece, holding it on an angle so that the bottom right corner of the piece that I am holding is lined up with the furthest right corner of the piece on the table. Tack this corner, then push the other side out until the seam is lined up. Im sure that made no sense to anyone trying to follow along, so I will try and grab a picture tomorrow.Have we all gone mad?
Reply:LMAO,Just to restate what Sn0 has already pointed out, William sometimes brings up a good point. The problem is it's so hard to separate the wheat from the chaf.If you choose to follow "his guidance" then I'd suggest you get your own "tin foil hat" because the radio waves in the area could be affected.Don't understand what I'm saying. Go back and read a hundred or so of Billy's posts.One week the aliens are taking over. Next week he's rewriting the laws of physics. Just goes on and on.But one things for sure. He doesn't get confused with facts. His mind is made up.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:I recently taught myself to tig aluminum (two weeks ago) and I was having hard time. I have been welding along time but this was a process I had never tried. I had used a wire feed on aluminum but never tig. The first day was bad, realy bad, so I got on this site and did a search of old posts on tig welding alum. The best advice that worked for me was floor the pedal all the way and then back off to almost half way, now my machine only has a 3/16 max capacity and I was welding 1/8 but if you start to cold you won't get a puddle and it seems to bubble up and you can't get started. I know these guys are a lot better at this than I am but give it try, start hot and back off.
Reply:Originally Posted by sn0border88As far as advice for tacking an outside corner joint together goes, this is how I like to do it. If the pieces are small enough to manage, I will lay one flat on the table. I take the other and stand it on edge on top of the other piece, holding it on an angle so that the bottom right corner of the piece that I am holding is lined up with the furthest right corner of the piece on the table. Tack this corner, then push the other side out until the seam is lined up. Im sure that made no sense to anyone trying to follow along, so I will try and grab a picture tomorrow.
Reply:Pinjas, I think one thing you need is to really learn to modulate the pedal better. Get a puddle formed, add a dab of filler, and then back the pedal off until that puddle is almost totally solid. Move forward just a bit, ramp the amps up a bit, see the puddle grow a bit, and add a dab of filler.Plain and simple, this is the way to do it; chill block, heat sink clay, it will not matter- this is the basics of the aluminum weld. For such a simple piece, a chill block is masking the symptoms of lingering, adding too much heat, not adding filler smoothly or evenly, and allowing for bad gas coverage with an unsteady hand... causing oxidation. All at once. No heat sink can fix all that.And then, after so much work...... you have it in your hand, and you look over to your side...... and the runner has run off. Leaving you holding the prize, wondering when the runner will return.
Reply:Pinjas, I made these images to give a sight picture to new welders in other discussions like this one, hope you won't mind if I include these links here as well?Looking down the tungsten without a cup, but with a filler rod off to the left, these images' colors are intended to separate the parts for better understanding. First, don't add filler until you give the weld enough energy/amperage/heat/power to melt the two edges of the outside fillet.Then, as you increase the pedal or slider on the torch, depending on the controls you have, you'd only add filler down low once the parent metal showed a molten puddle, and keep the rod tip inside the gas envelope if you can.Same image but from a lower angle the blue cone is the arc, and if your power supply has a HIFreq control cranking it up helps to narrow the arc cone, shown here in translucent blue. This will keep the heat in a narrow band, by comparison to a lower setting, and that will help you control the overall heat added to the parent metal, which you're trying to keep as low as you can while still creating a puddle or wet spot.same image again but the point of view is behind the torch and weld, to show the low angle of the rod and the feed point, you could even keep the filler rod lower than shown here and feed upward into the 6:30 position of the leading edge of the puddle.When you have some wet parent material make a very small wrist swing of the torch back in the puddle and thumb in some rod, when you swing the torch back to the center this will usually flatten the bead. That flattening on the outside corner is most often penetration as shown in an image above this post, but if there is a backer or chill bar then the flattening will often just fuse more parent metal -making a wider bead.THe arc cone is regulated by the distance of the electrode off the parent metal, the lead angle of the torch and the HiFreq if its adjustable. If you can't see the wet material cleaning to a shiny wet surface you may not have enough gas coverage and are not washing the oxide off the puddle surface with hot gas. Get closer and use less motion.To weld the outside corner you continue the torch step and swing advancing along the seam while thumbing in more rod, evenly and with the same amount added each puddle.Underneath the weld as it move along, again, showing the rod staying at the low entry position to the bead and the torch making a very subtle motion inside each puddle to keep the high freq from 'running' to the filler rod and to 'work' or melt the added filler as it chills the puddle.Each puddle has a slight cooling from the added filler, and for a bit the weld will 'hump' or dome up; unless you're welding too hot. If your puddle doesn't bulge a little when you thumb or dip some filler you may be working too hot a background amperage?Last image shown in front of the advancing bead, note the low angle of the filler and nearly uniform angle of the torch between the two pieces of parent metal. If you were welding heavy to light then the torch would angle more to the heavy material and less toward the light.This tank weld is not in very good focus but it does show a 'keyhole' or back fusion opening in the outside corner weld. When you do tanks or hull seams that will be one side welds and air tested this insures you're establishing a back bead or full penetration of the outside fillet weld.Better focus of a tank top weld using 5356 0.035" wire on 5086 H116, 0.160" sheet for a boat gasoline tank top.The same type of weld, but scaled down to 0.060" 5052 for a tool box using 0.025" filler wire.I hope this helps with your original question about outside corner welding using TIG on aluminum? Its not the simplest weld for the new aluminum welder so the advice to work on your flat bead to get some torch control seems like its in order to me too.CheersKevin Morin
Reply:I first thought Kevin's post should make this thread a "sticky candidate".Looking again I think Kevin's post needs it's own webpage or website!Outstanding work!Matt
Reply:Originally Posted by Matt_MaguireI first thought Kevin's post should make this thread a "sticky candidate".Looking again I think Kevin's post needs it's own webpage or website!Outstanding work!Matt
Reply:thanks for the kind remarks gentlemen,I guess the main question is; did any of this help Pinjas get a better idea of what he's inquired about?I do have some more image sets but not ready for posting, working too many hours. These images were already on the photobucket storage so they didn't take any editing or work to post, the others, and current projects, are all rough and will need to wait till freeze up to spare time to work on them.Pinjas, are we helping or just "preaching to the choir"?Cheers,Kevin Morin
Reply:Kevin - I don't know about Pinjas, but I can say that the bit about the keyhole being an indicator of penetration was helpful for me. I've been playing around with some welds, and I can see how the keyhole shape does seems to indicate you've fully penetrated through to the backside. This might not have fully sunk in for me, if it weren't for your educational picture presentation. And after practicing this a bit, I am having less burn-through now and maybe a bit better penetration control. So, good stuff thanks!
Reply:I can honestly say this all has been of great help. http://img706.imageshack.us/i/img2156co.jpg/ This is my third successful weld, at least I think it is successful. I put the second one in a vice and closed it flat. The two pieces are still together that I bent from an angle to a flat piece. I suspect if I tried to bent it back and forth that it would break. Anyway, success! I used 3 very thick pieces of aluminum angle around the corner and clamped the pieces together. My first dozen tries or so were failures because of the smallest amount of gap I had. I used no filler in these welds and I am impressed by their strength, I've got some 1/16ths filler that I'd consider using but I hate that filler. Something is wrong with the filler I have, it leaves a trail of carbon in the weld that you can see in the weld, uglyyy.I appreciate your efforts folks. As soon as I get some quality filler I might try to add some, I don't know if it would surely make it stronger. I've read online and in a welding manual than filler is not needed for this type of weld, but I've also read and heard that filler is needed as well. Who knows. This is 1/8th 5052 aluminum in this picture. I think it looks pretty great except the start and the end. I think I am using too much heat at the end and not holding the torch at the start. I imagine that weld to work very differently at the corner if there was a 'top' piece and a 'bottom' piece. At the end of the weld my hand slipped a bit. The weld was getting too hot for my hand to bare so I had to switch things up a bit and I wasn't perfectly comfortable. I think I am using the thickest glove I can find from now on for the hand that holds the torch, it's way too hot with those thin gloves, I think those thing gloves are used for very low amp pieces.Miller 330 a/bp water cooledI believe in gun control, I hold my gun with two hands. If you want to know why, click here.Buy American or bye America.
Reply:Filler WILL make a better weld..All you really need is practice practice practice...And more practice..How close are you holding your hand near the torch?You should not have heat issues in that amount of time...I can "melt" the fingertips on the Tillman MIG glove (And get it to glow red) I use on my torch hand and it really don't bother me at all..But that is after using 3 or 4 pieces of filler without stopping.....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:pinjas,while the exercise of floating instead of filling an outside corner may help in some alloys-- it will not fly with 50 series for a decent break-bend coupon. You'll need filler and no back ups unless you back weld after the outside seams are on, not possible on tank tops in most cases.Welding Web is working if you're able to read the replies and practice that information and improve your welds compared to hacking around by your self, so I' glad to hear the site is helping you get your 'hand in'; as they say in the trade.If your filler is not clean, water oxidized or contaminated in the carton, it will leave all sorts of a mess when you weld. Clean each rod with a ScotchBrite(TM) pad before using that rod. Just pull it through your palm, several times, holding a SBrite pad and that should clean the surface so if the rod is contaminated; the surface is stripped just before you use that piece of filler.regarding the weld, it looks like you're seeing the idea of puddle uniformity very well, and that means you'd already noticed that the amperage needs to slowly coast downward in a limited length piece like this? Otherwise the end will have a different weld profile and puddle width. The last puddle just needs to have less pedal/slider/potentiometer (amperage) when you 'back out' to keep the puddle uniform.Filler (5356) in 50 series alloys provides some alloying elements that help the weld's malleability -4043 will only make it brittle so avoid it like the plaque(!!) one bend, flattening is half the battle; now it needs to "come back" and remain one piece!I always fix a series of pipe clamps to keep my hands off the weld metal in small brackets and other items that will heat up. Long hull seams (I pay most attention to boat welding) allow you to lean and drag on the hull in most cases. I think its worth the time to rig a weld fixture or steady rest to make the weld go as good as I can make it.here is what I mean about welding jigs or hand steady rest fixtures.Looking good, keep practicing.Cheers,Kevin Morin
Reply:Thanks for the kind and well thought out responses. I always run my filler through a scotch brite stainless steel ball thing several times and then wipe it off with a wet with acetone paper towel to clean it off. I am fairly certain the filler I have is 5356, maybe I'll cruise over to my local welding shop and find some nice vice-grip clamps and 5356 filler.I've considered what I think you are referring to, a welding jig. I think some people tend to try to hold a weld in place with one hand or something, I've tried this myself and it is either extremely difficult or I fail entirely, and in reality there seems to be very few welds I can do that with.Practice practice practice practice.Miller 330 a/bp water cooledI believe in gun control, I hold my gun with two hands. If you want to know why, click here.Buy American or bye America.That keyhole picture is FANTASTIC!In the corner, the plates will appear to be further apart just in front of the keyhole, because their edges are starting to melt back. This guarantees complete penetration, because the center of the final joint is purely filler, but it also requires careful heat control.You're balancing on a knife edge. Too much heat or too little filler, and it will melt open, and blow through. Too little heat, or too much filler, and you'll stick your filler.Just the right heat and filler, and the keyhole will slowly move across the joint. Then just use filler to close it as you back off the heat at the end (with a little extra filler to make up for contraction as it cools).Larger filler that can be added to both sides of the keyhole at once is easier than really thin filler which you need to add to each side.
Reply:Kevin, that has to be the best tutorial explanation on any type of welding I have ever seen. The idea came across clear and describes the steps and what you should see and do perfectly. I could use a bunch more of your little mini classes!!!! Thanks for taking the time to help us out. Thanks!!!BobI'm spending my Kids inheritance, I dont like him that much anyway!!!!!!Enuff tools to do the job, enough sense to use em.Anybody got a spare set of kidneys? Trade?
Reply:I'm glad the images helped, I appreciate your kind words.I remember trying to learn and not having any instructions about what my sight pictures should be. The sketches were made to help others 'get there' in less time (years) than it took me to figure out what I was doing.I agree, rlitman, the key-hole balance is knife-edge but.... if you know you're looking for it, then you have a target. If a welder is thinking in terms of more heat = larger hole and less closure rate & less heat = smaller hole and less penetration; then it helps with quality practice beads.I think there needs to be a complete discussion on where to hold the torch's electrode in relation to the puddle so the key hole will be uniform- as well.thanks for again for your kind remarks,Cheers,Kevin Morin |
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发表于 2021-9-1 00:28:49