Aerospace TIG Welding Practice

let's do it we're going to be doing a little tig welding today on some cold roll steel in a aerospace test welding fixture made by abom 79 aerospace metals like 17-7 stainless and inconel 718 are super expensive so it makes sense just to get some practice on plain cheap cold rolled steel and while i'm welding this i'm also going to be experimenting a little bit with high speed pulse versus no pulse this is a ck worldwide mt200 it goes up to 200 pulses a second and i will set the background amps to around 40 a little bit later in the video i will compare a joint using no pulse at all and see if we can see the difference to get purge gas to the back side of the joint i'm using a dual flow meter you could also use two separate cylinders with single flow meters but the dual flow meter is an easy way to do it i'm just using regular old automotive vacuum line for the purge hose that's fine for cold rolled steel you might need something better for titanium and exotic alloys if you ever have to take a test like this you want to be careful not to use too much purge flow on the fixture that'll blow your torch gas away i'm using a o45 er 80s d2 filler because the thickness of the base metal is less than o 40. you can see that i have just a little whisper of a gap there the gap is totally not necessary you're going to get penetration pretty much but the gap helps a little bit in distortion so i got a nice low startup this machine has a 5 amp startup very helpful for aerospace type work like this let me show you that tack again here one more time we'll go over that i add a little bit of extra metal on my end tacks and i'll explain why here in a minute first thing you want to do is puddle both corners don't give it much amperage until you get them to join kind of stab the rod in there get them joined then they'll conduct heat evenly and you can add a few extra dabs and it'll give you a little bit of fudge factor when you're welding from or welding two will keep you from melting those ends away the aerospace welding specification allows for some melting ends away but when i used to administer this test i didn't allow that because all of our parts had ends that we didn't want to melt away i was probably lenient in other areas that i didn't feel were as important but melting ends away is something i felt like was super important so the way we administered this test was to start in the middle and weld to one end that way we could require a stop and a taper off in a crater out taper off in the middle to demonstrate the ability to not leave a crater crack which another that's another thing i felt was super important on aircraft parts welding to that tack where i added a few extra little dabs i'll show you that right now right there i start to taper off you can see i did not even come close to blowing the end away because i had a little extra heat sink there a little extra dam there of extra mass of extra metal with that extra few dabs on that tack here it is in slow motion as soon as i get right about here i start backing off the pedal taper off and back up the arc a little bit and it doesn't leave a a crater crack or a mark or a crater hole or anything like that and keeps the end intact and the objective here is you know if this was an aircraft part if it was a crack and you were welding out to the end you'd want to be able to have metal there that you could grind off and then maintain your dimension you don't want to blow the end away all right once that's welded now we start on the other end and we weld to the previous weld and then taper off when we get there so that we don't leave a crater crack there see how that extra little bit of metal kept me from melting that end away there even though i set the amperage to about a hundred it's this is showing the average readout here for the actual welding and i'm not quite full pedal this is real time this is the speed that i'm traveling i'm trying to keep that hot tip of that rod shielded with the argon coming out of that cup trying to maintain a nice tight arc length you can see the jazzy 10 is doing a really good job of shielding a really big argon envelope there that's always helpful on aerospace test here i'm coming up on the previous weld so i slow down a little bit add a little bit less filler keep traveling taper off the amperage and kind of tear drop it out now i know that not everybody watching this is facing an aerospace welding test but this is just good fundamental principles for basically any kind of sheet metal welding if you're tying into a previous weld that's a good way to do it now the reason i required that taper off thing in the middle of the test joint is because that's the most likely place for a crack especially on crack sensitive alloys let's take a close-up look at that now let's take an even closer look with some magnification and let's zoom in a little bit that's where you're likely to have a crack right there and it happens a lot on chromoly on 17-7 stainless on inconel but if you keep traveling as you taper off while adding less and less filler you can avoid that crater crack i'm going to swap over to the ceramic version of this cup right now and just show you how easy that is to do it's got an o-ring on there for the clear cups but all you need to do is pop the o-ring off that adapter kit and thread the ceramic cup on there and the ceramic cup's a little bit more durable i like to use clear cups for filming kind of helps everybody to see the arc a little bit better i'm turning the pulse off now and i'm just going to weld it with straight current about the same amperage output though there's slight differences 200 pulses a second is is a lot and what it does it stiffens the arc up but it's almost like welding without pulse there's some just some really subtle differences in a lot of cases i would prefer to do this this type joint with no pulse at all but you know the machine's got it and so i like to experiment that's how we learn all right let's do that other half now just like we did before we're going to come up on that previous weld just the same old fundamentals trying to keep a tight arc move along at a consistent rate keep the hot tip of the filler shielded by the argon and as we move into that previous weld quit adding filler keep moving forward taper off the amperage to zero and that's what prevents a crater crack especially on crack sensitive alloys like chromoly precipitation hardening stainless inconel 718 etc there's the no pulse there's a 200 pulses a second definitely a little bit of difference not like night and day now for this video i used 332 electrodes 1 16 would have been better but as long as you sharpen them like a needle like this you can almost do the same thing as you can with a 1 16 electrode so i'm going to run a bead on the edge of this o38 material with the electrode sharpened really sharp really long taper that's what i would do this is really good practice for an aerospace test to be able to run a bead along the edge of something about this thickness that's the kind of heat control you need to practice for aerospace welding the great thing about it is that you can just grab some cold rolled steel sheet metal like i have here and use an incandel filler rod or hastelloy filler rod and work your way down to as thin as you can do and do edge build up like this and that's some of the best practice you can get for practicing for an aerospace welding test you

Channel: weldingtipsandtricks

Views: 62,812

Rating: 4.9728742 out of 5

Keywords: tig welding, aerospace welding, aerospace tig welding test, d17.1, pulse tig settings, jazzy 10 tig cup, furick cup, gtaw, gas tungsten arc, welding tips and tricks

Id: LbPqCDflnUY

Length: 8min 19sec (499 seconds)

Published: Mon Jul 26 2021