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  • tungsten stability ac tig aluminum problems

    Ive been doing a lot of aluminum tig work lately with a Syncrowave SD 180 which i had thought was (and according to specs is) a bit under powered for 3/16" and 1/4" plate. Ive recently got a helium argon mix to get a bit more heat at the weld which is working really well. I no longer need to run the machine much higher than 130 amp to do the work. I do find though that the width and length (or overall mass) of the work also makes a big difference, and when working on larger sections, still have problems. I can make the welds, but it takes a long time. I know i could preheat and maybe i will, but the biggest problem seems now to be the tungsten. I've been using 1.5% lanthinated, both 1/16" and 3/32" on a #17 air cooled torch with a medium size gas lens and 5, 6, and 7 alumina nozzles. All of these work but i can't get a very stable tip on the tungsten. It not only balls, which is fine, but the ball gets too big and or sometimes is lopsided and or becomes asymmetrical etc.. kind of a mess. The question i have is, and sorry for taking a while to get to it, would a water cooled set-up help with tungsten deforming? The torch doesn't get as hot as it used to now that i have the helium mix which allows me to lower the amps, but I've got to figure out how to stabilize the tungsten. Maybe i just need 2% lanth? I have also tried pure, with similarly poor results.

  • #2
    As you discovered pure tungsten is not the answer. The 2% I believe would help and I'd stay with the larger diameter. Is the SW SD 180 an inverter? If not you could try Zirconium tungsten, it will hold up much better on AC welding.
    Richard
    West coast of Florida

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    • #3
      thanks Ltbadd, I'll try 2% lanth. For some reason I've only been able to get 1.5% The SD180 is a transformer machine. Its true that larger tungsten seems to hold up better, or at least thats been my experience, but when it balls, you are working with a larger sphere, whereas when the 1/16" balls, its still quite compact and directional.. but more susceptible to the problems I'm having; misshaping, burning back, etc.
      Last edited by Andrew J 649; 02-10-2016, 05:02 PM.

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      • #4
        I have to order the 2% lanth tungsten. My LWS supply believes it to be a unicorn of something. You will most likely have the same situation though. I have it from time to time and all I use is the 2% lanth. I admit, I've never used the 1.5% so maybe it's night and day, please let me know how it goes, I tend to have similar issues when mixing some helium in there.
        Last edited by ryanjones2150; 02-13-2016, 12:23 PM.

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        • #5
          Originally posted by ryanjones2150 View Post
          I have to order the 2% lanth tungsten. My LWS supply believes it to be a unicorn of something. You will most likely have the same situation though. I have it from time to time and all I use is the 2% lanth. I admit, I've never used the 1.5% so maybe it's night and day, please let me know how it goes, I tend to have similar issues when mixing some helium in there.
          We use 1.5 (gold) all the time. Mainly because that is what our local supplier (Airgas) keeps on hand. We burn High amps all the time. It works just fine.
          I really doubt you need to spend money on tungsten to fix this from happening.
          How you are shaping it could be an issue though. How far you have your stick out could be another also.
          As far as I can tell.....I do feel that the use of water cooled DOES help with tungsten lasting longer although there should be no actual reason for this in a perfect scenario. That said, I would get a water cooler with the better flex hoses. I would dump all the 17 style consumables, and go to a 20 torch.
          Then you are good to go if you upgrade your power source in the future.

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          • #6
            Thanks ryanjones2150 and FusionKing, and Ltbadd earlier. To answer your questions FusionKing: Ive been very conservative on stick out finding this to give the best results regarding contamination, which is a whole other topic. I'd say 3/16" to 1/4" of stick out using a 3/8" and 7/16" ID alumina nozzles. I usually grind to a cone (a bit less acute than for steel) on a diamond wheel, then ball the end slightly using dc positive on a piece of alum or brass. My latest tests (done after my initial post) have been with an 1/8" 1.5% lanth tungsten. Again i still don't have 2%. This actually seems a bit better in that i can ball the tip without balling the entire end. Hard to explain, so I've attached some pics. Two different set ups for the air cooled #17 and a sample weld in 1/4" 6061. Again, its easy to get a reasonable weld on a small part like this, but on larger plates (not thicker but wider & longer) is where the problems start.

            It looks like a fairly large aluminum job is about to land, so i might be able to step up to a water cooler and wc torch or even a used sync 250 with integrated cooler, if i could find one at the right price. And yes, #20 style torch would be really nice. In any case, if the job comes though, i'll be wanting to get to the bottom of the tungsten issues in a hurry.

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            • #7
              The question was asked regarding water (liquid cooling). I believe it would help to keep the ball under control, especially with 2% Lanthanated tungsten. A liquid cooled torch outfit is a good investment, especially for longer jobs.
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              • #8
                I have zero experience with a water cooled tig, so I have nothing to add to that and haven't the slightest idea if it would help the balled end of tungsten or not. Further more, I've never used 1.5% lanthanated tungsten. Maybe before you dump the money into a water cooled doohickey, order some 2% lanth and see if it solves your problem. If you're close to me, I'll give you some. I'm in Beaumont Texas.

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                • #9
                  Jody at weldingtipsandtricks.com has 2% Lanthanated electrodes for sale. (I have no financial ties to his business. )

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                  • #10
                    I run 2% thoriated 1/8" dia. tungsten on a #17 air cooled torch with a #8 or #10 cup. I use this setup on any aluminum 1//8" thick or thicker. Just my guess but your tungsten is over heating which is why you are having an issue keeping a good tip on it. Switch to the next size bigger. Also your stick out is a little much. I run flush to 1/8" stick out unless I absolutely need more due to joint configuration.

                    The reason you are having issues on larger pcs. is the fact that it is a huge heat sink & requires a lot more amps which over heats the tungsten. If you are running lower amps & just sitting there pre heating then it can happen also. Try upping the amps so you can get a puddle faster & then moderate with the peddle.
                    Last edited by MMW; 03-03-2016, 06:30 AM.
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                    • #11
                      Originally posted by Andrew J 649 View Post
                      Thanks ryanjones2150 and FusionKing, and Ltbadd earlier. To answer your questions FusionKing: Ive been very conservative on stick out finding this to give the best results regarding contamination, which is a whole other topic. I'd say 3/16" to 1/4" of stick out using a 3/8" and 7/16" ID alumina nozzles. I usually grind to a cone (a bit less acute than for steel) on a diamond wheel, then ball the end slightly using dc positive on a piece of alum or brass. My latest tests (done after my initial post) have been with an 1/8" 1.5% lanth tungsten. Again i still don't have 2%. This actually seems a bit better in that i can ball the tip without balling the entire end. Hard to explain, so I've attached some pics. Two different set ups for the air cooled #17 and a sample weld in 1/4" 6061. Again, its easy to get a reasonable weld on a small part like this, but on larger plates (not thicker but wider & longer) is where the problems start.

                      It looks like a fairly large aluminum job is about to land, so i might be able to step up to a water cooler and wc torch or even a used sync 250 with integrated cooler, if i could find one at the right price. And yes, #20 style torch would be really nice. In any case, if the job comes though, i'll be wanting to get to the bottom of the tungsten issues in a hurry.
                      In your first picture the dis-coloration of the tungsten shows your gas was not on or not flowing.
                      The tungsten in the second pic looks overheated.
                      In the third pic you have noted 90 amps and that looks like 1/4" aluminum. 190 amps would be close if that is indeed 1/4" aluminum.

                      Griff
                      Last edited by griff01; 03-03-2016, 07:57 AM.

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                      • #12
                        Thanks all. I ordered some 2% a few days ago, so i'll let you know how it goes (and thanks for that offer ryanjones2150, but I'm a ways from you in new york). I emailed Jody to inquire about placing an order for a 10 pack of 3/32" 2%, a few different gas lenses, and collets, and alumina cups. It could be that writing in for a custom assortment of things is not the way to go, as i didn't hear back.
                        MMW, i agree i am having overheating issues on the larger pieces i have to do (cabinetry-image attached). The problem I'm trying to address is exactly as you say - large parts - large heat sink and getting the tungsten to survive the task. I also find, as you said, that minimizing stick out helps a lot, but i don't find i can get into a corner with a zero-to-1/8" stick out, so i step out to 3/16" or even a bit more to get it...could be the problem. Griff, I'm not sure what caused that particular color on that one. So i went ahead and re-did a bunch, all different tungstens all at the same amperage, pedal down full. What you'll notice from the images is that i set the amperage quite low. 75 amps. For 3/16" everyone would agree I'm sure, that is very low. But keep in mind three things. One- I'm using a helium argon mix, and Two- these are tiny little parts. Three- i'm waiting about 10 seconds to initiate the weld before moving forward. Even at that amperage, once the piece is hot and puddle fused, the rest happens very quickly. About another 8 seconds or so.
                        So what you'll notice is that all the tungstens i used worked at this amperage - lanthinated, pure, and even thoriated (just because i had it). But in two weld image i bumped up to 160 amps, which is easily what i'd need to do the larger parts, like the cabinets. The last image shows the 1.5% lanth tungsten afterward. That ball was out of control! Totally lopsided and getting bigger as i went forward.
                        Last edited by Andrew J 649; 03-03-2016, 03:15 PM.

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                        • #13
                          Originally posted by Andrew J 649 View Post
                          Thanks all. I ordered some 2% a few days ago, so i'll let you know how it goes (and thanks for that offer ryanjones2150, but I'm a ways from you in new york). I emailed Jody to inquire about placing an order for a 10 pack of 3/32" 2%, a few different gas lenses, and collets, and alumina cups. It could be that writing in for a custom assortment of things is not the way to go, as i didn't hear back.
                          MMW, i agree i am having overheating issues on the larger pieces i have to do (cabinetry-image attached). The problem I'm trying to address is exactly as you say - large parts - large heat sink and getting the tungsten to survive the task. I also find, as you said, that minimizing stick out helps a lot, but i don't find i can get into a corner with a zero-to-1/8" stick out, so i step out to 3/16" or even a bit more to get it...could be the problem. Griff, I'm not sure what caused that particular color on that one. So i went ahead and re-did a bunch, all different tungstens all at the same amperage, pedal down full. What you'll notice from the images is that i set the amperage quite low. 75 amps. For 3/16" everyone would agree I'm sure, that is very low. But keep in mind three things. One- I'm using a helium argon mix, and Two- these are tiny little parts. Three- i'm waiting about 10 seconds to initiate the weld before moving forward. Even at that amperage, once the piece is hot and puddle fused, the rest happens very quickly. About another 8 seconds or so.
                          So what you'll notice is that all the tungstens i used worked at this amperage - lanthinated, pure, and even thoriated (just because i had it). But in two weld image i bumped up to 160 amps, which is easily what i'd need to do the larger parts, like the cabinets. The last image shows the 1.5% lanth tungsten afterward. That ball was out of control! Totally lopsided and getting bigger as i went forward.
                          My bad. I missed the helium mix in the original post.

                          Griff

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                          • #14
                            First question is why are you using such a small cup? Larger cup should help your gas flow & cooling. I run a #10 cup most of the time & have no issues getting into a corner with about 1/8" maybe 3?16" stick out.

                            Next is why aren't you switching to a larger tungsten? 3/32" is to small for the job you plan to do. You are clearly melting it off which means you need to go bigger.

                            For the cabinets I would step up to 5/32" & if you are staying with air cooled maybe think about getting a #26 torch. A 17 may suffice but will get hotter than a 26. I use the cheap torch handles from weld city. I think of them as disposable at $10-12 a piece.
                            Last edited by MMW; 03-03-2016, 08:19 PM.
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                            • #15
                              I agree on moving up to a larger tungsten. One thing you said in there Andrew is that you're waiting ten seconds before you get moving...I don't think I understand why. I generally take an extra second or so and let the cathodic etching do its thing, but if you've cleaned and prepped properly, why so long? Heat input is more a function of duration than amperage. Maybe you can clarify what you're talking about there? As for the odd color of the tungsten in your pics...how long is your post flow?

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