TIG Talk

I haven't picked up a TIG torch for about a year now and out of the blue I got the itch again. In all, I have probably less than 10 sticks of filler through a TIG welder, so I'm still very much a rookie. I know we don't all TIG weld, but I think there is enough interest in it to make a thread for tips and tricks. Well, I have no tips or tricks to offer, but I'm willing throw some projects out there for the experienced guys to pick over so we can all learn together.


In this project I needed to make some trailer stakes with some strap pockets welded to them. The material I used was 3x1.5x1/8" rectangular tube as well as 2.5" square 1/8" tube.




Getting my parts lined up.


These are settings I went with. The 151 seems very high to me, but maybe not. I did have my foot to the floor almost the entire time. I did play around a bit. As I backed off the pedal I could really see a difference. My filler would not just drop into place. A lot of times it would end up sticking to the tube and I would have to bring the torch over to it and melt it to free it up then go back to my last bead and kind of start over. Maybe I wasn't sticking the filler into the arc far enough or fast enough? I was using 1/16" filler rod.


This is how I prepped the electrode. I use a dedicated grinder to sharpen them, holding them parallel to the wheel. It's kind of hard to see, but it's ground down to a pretty sharp point.


This is the position I was welding in. I would start at the top and pull the torch towards me. I would bring the filler in from the bottom of the picture and most of the time it was leaning up against the square tube to help keep it from bouncing around.


This is how most of the welds turned out. I made a total of 20 of these passes. It's got to be way too hot. Maybe it's just that I had to go slow because of the large gap between the flat surface of the rec tube and the round corner of the square tube. It was a pretty large gap to fill. The top of the weld is undercutting and the HAZ is pretty large.


This picture shows how I was close to burning through, although I never did. The stakes ended up warping quite a bit (not a big deal on this project) right at this strap pocket. From here to the end of the stake is 24 inches. The end of the stakes would be about 1/2" in the air.


This picture shows what my electrode looked like after 7 passes, or about 21 inches of welding. I assume this is normal wear? I could really start to see how my arc went from a very narrow line and ended up as a wide arc, like an umbrella. After sharpening it again it went back to a narrow line again and I could be very precise with where I created a bead.


I found welding these lines to be the easiest ones as the filler just kind of dropped into the gap and filled nicely.

One thing to note is how much filler I used. In a total of 60 inches I used 3 1/2 rods. Does that sound about right?


I needed to build 10 stakes and switched over to MIG after the first 5 were done with TIG. You can see how uniform the welds are. Overall I was pleased with the outcome. I just need figure out if the welding could have been done colder with less/no warping.


The bottom 5 are the ones I did with the MIG welder. I really flew through them. Much smaller HAZ and no warping.


Overall I really enjoyed this project. My end game is to get proficient at TIG welding aluminum. I have done it a couple times and accomplished what needed to be done, but I know it could have been done better. I'm going to try to TIG steel more often so that I can develop all the hand/foot/eye coordination more. One thing I really tried to do this time was moving the filler rod through my hand instead of just moving my hand closer to the work as I used it up. It's hard to do!

 

[UNSTUCK]

Here's the next project I worked on. I built this socket a couple years ago. It started out as a 13/16 bud socket that I never used. Then one day I was removing (or trying to remove) a 3/4" SHCS with my 3/4" gun with no luck. I pulled out the 1" gun but didn't have a socket. So I took this one and cut up an Allen wrench to make one. I MIG welded the two parts together and got the job done. I have used this new socket many times since and at one point the weld started cracking and had since cracked all the way around. Why did it crack? Well I know the weld was too cold, but I also believe the chromoly socket didn't really like the welding. Also, it has seen some abuse.

So I ground out the cracked welds, removed the Allen wrench and cleaned things up a bit. I turned up the welder to 200 amps and went for it.


I did one flat at a time then rotated the socket. So there is a lot of stop and starts. Ideally I wouldn't do that when MIG welding, but I don't know if it matters while TIG welding. The thing I've noticed about tig welding is that you don't have the cold start like MIG welding. I can sit there and heat up the starting point a bit before adding any filler. You can't do that with MIG, so I assume it's okay to do several start/stops. I did a small root pass and then went around a second time where I tried to do more of a weave pattern to get larger beads. If I had to guess I'd say it was a little too hot, but I didn't try backing out of it with the pedal.

My future aluminum project has a lot of 3/8" thick, 1" diameter circles that will be welded to 1/2" plate. Can I do them just like I did this?


After cooling off I got ready for a test run.


I hammered on this for probably 30 seconds after it was tight. Didn't seem to phase it. Time will tell if it holds up better than the MIG did.

 

[zmotorsports]

I'm not sure what filler thickness you were using but in my experience even on thicker weldments I generally don't run much over around 160-170 amps. IF I need to make multiple passes I would rather do that than go over that amperage and using 1/8" filler rod. This is mainly on carbon metals. On non-ferrous materials I have used higher amperage and 1/8" filler but that is due to the rapid heat dissipation that non-ferrous materials exhibit.

I tend to use smaller filler rods and feed at a faster rate and enough current to melt the parent material.

Also when I feed the rod I like to slightly raise the torch ever so slightly and then dip the filler rod into the leading edge of the puddle and push it in aggressively to the point of watching the puddle actually raise up towards the tungsten.

I hope that makes sense.

Mike

 

[UNSTUCK]

That does make sense. I was using 1/16" filler on all these parts. I didn't notice it on the socket, but doing the stakes the filler rod was sometimes sticking to the stake before it got to the puddle. Maybe I was just missing my mark when putting it in. I'll try lifting the torch a bit next time and see if that helps get the rod into the puddle. At least I never hit the electrode with the rod.

What would you set your amps to when welding 1/8" to 1/8"?

 

[zmotorsports]

As a general rule use the 1-amp per .001" material thickness. I usually stick to that but will tweak it a bit depending on initial heat input.

If your able to get a molten puddle where you can start adding filler and moving within about 3-4 seconds you are very close on amperage. If it takes longer than that you are too low and will have a problem keeping the puddle moving along in a nice fluid manner. Too soon and you're just dumping way too much current into the part and will end up fighting undercutting.

So to answer your question if I were sitting down to weld two pieces of 1/8" material together I would start around 125-135 amps depending on joint configuration. Example, a "T" joint will need slightly more heat than an open corner joint.

Mike

 

[UNSTUCK]

Now that you mention it, I think I have heard of the 1 amp per 1 thou. rule. I need to put that on the machine so I remember it. Would you say that this advice is the same for AL?

 

[zmotorsports]

For aluminum I will usually bump that 10-15 percent as non-ferrous materials dissipate heat so fast.

For example using the same 1/8" only aluminum, I would probably start in the 140-145 amp range.

Mike

 

[UNSTUCK]

Would you set the amp setting to 140-145 as the max or would you go a bit higher and then use the pedal to dial it in? I wish there was an easy way to recall what amps were actually being use during welding. I might set it for 140 but if I back off with the pedal I don't know where it was really at. Probably doesn't even matter. Once I get enough experience I'll just be able to look at my puddle and know what needs to happen.

 

[YROC FAB.]

Would you set the amp setting to 140-145 as the max or would you go a bit higher and then use the pedal to dial it in? I wish there was an easy way to recall what amps were actually being use during welding. I might set it for 140 but if I back off with the pedal I don't know where it was really at. Probably doesn't even matter. Once I get enough experience I'll just be able to look at my puddle and know what needs to happen.

I would say i have enough experience and thats exactly what i do. With aluminum because it dissipates the heat so quickly it takes longer to establish a good puddle, I will crank the amps way past what it actual takes to weld it just so i can quickly get a puddle going. pretty much any time i weld 1/8" or thicker with aluminum i will have my dial set at at least 250 amps. After 250 amps 1/8 tungsten starts to boil and gets unstable.

Newer digital welders or even some older ones will show you exactly what amps are being used while welding. You just need some to watch them while your welding.

 

[zmotorsports]

Would you set the amp setting to 140-145 as the max or would you go a bit higher and then use the pedal to dial it in? I wish there was an easy way to recall what amps were actually being use during welding. I might set it for 140 but if I back off with the pedal I don't know where it was really at. Probably doesn't even matter. Once I get enough experience I'll just be able to look at my puddle and know what needs to happen.

Sorry, didn't see this until now.

For me, on the same 1/8" example I would start around the 140-150 amp range and see how fast the puddle establishes on the cold parent material. If it is longer than about 4-seconds I would bump it to maybe 160 but I would say the 140-150 is going to be close. A lot of my co-workers set the amperage way high and then modulate the puddle accordingly but I don't like to have to move the puddle that much.

Think of the pedal in this fashion, whatever the amperage is set at on the machine, THAT is what the amperage is at full pedal. At anything less than full pedal it is a percentage of that max amperage. If the amperage is set at 160-amps then when you max it to establish the puddle you will in fact have 160-amps at the work. When you lift to say 1/2 pedal you will in fact have 80-amps. If you set the amperage way up there at say 250-amps then when you go to 1/2 pedal you are still delivering 150-amps which can in fact be too much when you are coming to an edge.

As the weld is progressing towards an edge you are pushing that heat to the edge and if you are not using any kind of chill block or other manner of dealing with the heat all of that heat can build up at the edge and with that kind of amperage you can melt through at worse case or at least get an overly wide and low puddle as the weld will flatten out more than you want it to.

It may be a personal preference but I like to set my amperage at the machine for good puddle establishment and then have better control with the pedal throughout the range of the weld vs. having way too much amperage throughout the weld that I'm trying to control with very, very small movements of the pedal. I don't worry so much about what the amperage is throughout the majority of the weld but want that relatively quick puddle establishment and still have incremental control with the pedal throughout. Again, probably more of a personal preference.

 

[zmotorsports]

I know you've been talking about aluminum but here's a little trick that I use a lot when tacking carbon steel components together prior to final welding. It doesn't work quite as well on aluminum.

One of the problems with TIG welding is that both hands are being used to weld, one with the torch the other with the filler. This complicates the task of tacking components together. Granted there are times I use my welders helper which is a weighted third hand to hold something but many times just to tack a part it would be much simpler to have a free hand to hold the part.

I like to use a method called "blast tacking". I will bump my current up to nearly twice what I would weld the material with and hold the part with one hand and the torch in the other. Get the tungsten close to the part and very quickly depress the pedal and the high amperage will quickly melt the parts together. This works twofold because now when you want to do the final weld there isn't a big bump from the tack weld and you can merely weld right over the top and no one's the wiser.

Here is the final welded bung and you can see that I merely welded right over the top of the tack without having to use a die grinder to flatten out the tack weld.

I hope that little trick works well for ya as it has come in very handy for me over the years.

Mike

 

[UNSTUCK]

I have heard of blast tacking, but haven't needed to do it yet. I'm also very interested in TIG welding trick for every material, not just aluminum. I am in the process of building a third hand as well, based off of what you posted in the other thread. I kind of want to make the "finger" screw into my weight so that I have the option of making a few different fingers for it. That may or may not be needed. The scrap I have and wanted to use is VERY hard and not playing nice for drilling and tapping a hole for the finger to screw into.

Thanks guys for all the info so far. I'm looking forward to pulling the TIG out again to play with soon.

 

[UNSTUCK]

So I decided I needed to copy Mike and build a "third hand". Should have made one of these a long time ago. I can see how beneficial it will be. My original idea was to make it all interchangeable. I wanted the legs and finger to bolt on so that I could use different lengths of them if ever needed. I wanted to drill and tap my body but then found out it was heat treated and not worth the effort. I welded legs on and then welded a nut on the body which will still allow me to change out the finger.


These are all junk parts I scavenged from work. The body weighs about 10 pounds and puts a pretty good bit of force down on whatever I'm holding.


I just heated and bent the legs.


A blast tack that worked out great. It held the two parts together while allowing me to make some adjustments in the positioning.


I then bent the finger and threaded one end of it.


I then TIG welded a 1/2" nut onto the body. I tried welding it at 160 amps, but it turned out a little cold, I think.


The final product. A pretty basic project that I'm sure will help me out in the future. And it gave me an opportunity to do more TIG welding.



So this project stumped me a bit and is now forcing me to ask my next TIG welding question, and it might be a stupid one:

Am I getting electrocuted?!?!?!

I swear I feel like I'm getting shocked on occasion. Here's what happens: Sometimes when I step on the pedal to initiate the weld, nothing happens. No arc is formed. I then hear clicking/buzzing coming from the machine. I then feel like I'm getting shocked. Seems to be stronger when I'm leaning against the work surface, but also happens when I'm not touching it. It must be a product of the HF start, but I'm not sure. Seems like it happens more often when I'm holding the torch really still. If I move it a little bit when the clicking starts it will usually start an arc and then the clicking sound goes away. One time I got shocked and jerked away from the project. As I did that the arc was then formed. You can see the arc trail on the picture above of the welded nut.

So, is this an inherent feature of HF starts or am I doing something wrong? I checked the connections on both ends of my ground cable and tightened them as needed. It didn't help any. Maybe its a bad connection inside the machine?

 

[zmotorsports]

Great job on the third hand, welder's helper or whatever you want to call it. Great design and execution. One thing that I did to mine was used some silicone bronze and built up the contact points slightly with it. This will create a very good grounding connection between the work surface and the part that you are welding and could be your shocking issue. The high frequency (HF) is trying to jump and taking the path of least resistance so if the ground is not a good one it will go through your arm or whatever body part is leaning against the work surface to get to the work. This is why it is so important to clamp the ground as close to your work as possible. I still like to clamp my ground to my fabrication table the majority of the time and then I simply stand up my third hand which creates that connection between the table and the work piece.

Try that or clamp directly to the work piece and see if the shocking goes away. If it doesn't it could be a bad connection at/in the machine but I've found it is generally at the work.

Mike

 

[UNSTUCK]

So being shocked isn't too uncommon? Can't say I've ever been shocked with MIG, and I think a LONG time ago was shocked once while stick welding in the rain.

I thought about the silicone bronze you had mentioned before. I didn't know if it would do any good with my screw on finger. I think I will replace the ground clamp with a better one and make sure I clamp to the work and not the table to see if that makes a difference.

Thanks for the information.

 

[zmotorsports]

I wouldn't say it is common but it's not uncommon. I think the biggest difference and why it is more prevalent when TIG welding compared to MIG welding is due to the high frequency start.

As for the silicone bronze on the tips of the third hand I think it greatly reduces arc marks on your parts.

Trust me, I don't know everything there is to know about TIG welding and I am hoping to pick up tips and learn just as much as anyone so this is a good topic to help us all learn.

And keep us talking about something other than that other "thing" right now.

Mike

 

[Unimog]

Love this thread! I've got a decent tig machine that I need to get setup and start playing with.

 

[UNSTUCK]

Here's the next project. I need to weld these two pieces together then weld a tube on after that. I have almost no AL experience. So looking for guidance on this one. This is in no way structural. It's basically just a hand tool for pushing items. The main piece is 5052 at 3/16" and the small section is 6061. I was told that welding them together shouldn't be a problem, but that was from an unreliable source.




I started with this gap, but when I started the arc it was all over the place. I couldn't get it to settle down to start a puddle. I moved the two parts together so they were touching. That seemed to help, but I don't know if that was the right thing to do.



That's rough to look at! Reminds me of my days as a rookie stick welder. I'm sure I was welding cold, but I don't really know much else that I was doing wrong that could have made this turn out better. One thing to note, I had the heat up a bit hotter, but my filler was getting blown away in drops before I was sticking it in the puddle. Once I turned it down I was having much better luck with the filler, but as you can see that's where it starts to build up, like a cold weld. I believe I also turned the balance up a bit at that point. Maybe the balance needs to be turned back down a bit.


The filler rod I used. I was also using a #8 cup with a 1/8" 1.5% lanthenated electrode.


The settings I used. Pulse was off so those settings shouldn't matter. I believe arc force is only used while stick welding. Frequency was high and Balance was lowish. 5 second of preflow and 12 seconds post flow. Not sure about up slope, down slope, and start and end amps.


I have three more of these to weld up, then weld the tubes on. Any suggestions to clean these up a little bit? Should I be running with pulse on? What should the amps be?

 

[SnwMnkys]

It doesnt look like your pieces were properly cleaned before welding and it contaminated the weld. Maybe im not seeing it though.

 

[frieed]

I'm no pro, but I'm more suspicious of your amps, definitely too cold on the right side and you nearly burned through on the left from moving too slow. Without pulsing, on that thickness, I'd expect at least 180A then back off with the foot pedal as it heats up. How long does it take to create a puddle? What does the back side look like? I'd guess that you are moving quite slowly (very small ripples).
It looks like total heat input is quite high but contrary to what you might think, more amps and moving faster lowers the total heat input.
When you try to tie the tube into that it will be like a T-joint and need even more heat.
If you have a bit of comparable size scrap and some time I'm open to you giving it a shot at my place to see if I can spot the issue. you can bring your machine and I have a gas bottle and/or we can use my machine as well. I'm available Fri-Sun all day, or evening if need be.