Thread: TIG welding gas flow and current

I looked around for a while but found info on TIG settings difficult to find. I.E with a lathe, you can find heaps of useful charts for how to set feeds and speeds for differing metals, with TIG welding, I could find no such beast.

From what info I cobbled together I settled on 10 litres per minute pure argon flow with a 2.4mm 2% thoriated tungsten and a #5 cup. Not sure how I came to that conclusion, but it works well for what I have been doing so far, which is welding 2mm mild steel RHS.

I played with some 1.2mm stainless sheet using the same flow setting and the welds were beautiful and stood up to the destruction test.

Around 7 lpm is enough according to my TAFE course so you're pretty close.

Ok thanks for that, at least it seems I'm not the only one having trouble finding this information I'm certainly going to look into some of these night courses at TAFE once things settle down at home, they sound pretty good even if I need to wag half the classes.

I figured it was better too much gas versus too little, but didn't want to use any extra for no particular reason. How about the current? Would it be true to say that with more current you can simply get more heat in and will need to weld faster?

Stainless or mild steel?

Mild can set current from about 60 to 90 for 2mm. Stainless you can almost halve or take a 3rd off what you use for mild.

I think the CIG handbook might have a table somewhere:
http://www.thermadyne.com/IM_Uploads...%20213-400.pdf
If not the miller one does:
http://www.millerwelds.com/resources...Book_Chpt6.pdf

In practice, current settings tables are usually just getting you into the ball park so you don't blow a hole through it. You adjust the current with the pedal based on your torch angle, and how close you hold it.

What I tend to do is try tack it up with a moderately high end of the recommended range. Then judging by how quickly the tack forms I tweak it up or down either via the settings or laying off the pedal a bit.

Really not good to try go faster as a beginner. Believe me I tried! It's better to go slow and get your coordination going. If you only do a short weld and have to stop because it's getting too hot, it's better than making a mess! Messes are harder to fix.

"I figured it was better too much gas versus too little"

Me too, hence why I settled on 10. I might dial that down to 8.

Re amps, I start with 40 amps per mm to get me ballpark, then adjust from there. I have been typically adjusting down from that figure though, but am yet to blow through a tube.

Ok, well sounds like I fluked some settings pretty close to the mark. 60 amps seems ok, but I can now see not having control over that is a pain (obviously I can adjust it, but it's either on or off). Likewise I hadn't come close to blowing through anything except when I was trying to do a fillet from behind. I couldn't see the surface facing away from me so I just kept putting more and more heat on it (it was a real awkward position) and went through. Once I realised I changed things around so I could actually see what I was doing and was amazed how easy it was to fill in the hole. Ground it back and redid the weld and you literally can't tell where my "oops" was, again I find the TIG just amazing.

Next time I'm at the welding store I'll get some different filler rods for other materials and have a go at aluminium for a giggle.

TIG welding is fantastic thats for sure. It just cant be beat for versatility nor appearance.

Re adjusting, I dont use a foot pedal. Im talking about test, then adjust at machine, test again, do job. If im welding up some 25x25 x 2mm RHS I cut off a couple of bits, practice welding them together and once I have the amps right, I do the job. I have found not using a foot pedal has improved my welds dramatically. By taking your mind off the foot pedal you are better able to concentrate on torch angle. Its more important to have that correct than it is to simply blast in a few more amps in through the foot pedal when a poor torch angle results in a shallow pool.

Originally Posted by Pete F

Ok, well sounds like I fluked some settings pretty close to the mark. 60 amps seems ok, but I can now see not having control over that is a pain (obviously I can adjust it, but it's either on or off).

It's definitely doable without the pedal. I've tried it without the pedal for my first vertical up welds on aluminium. I was taught to do it standing up and I disconnected the pedal to stand comfortably. Now that I'm used to it I tend to use the pedal on vertical up. The little pieces we weld at TAFE can't hold a lot of heat so backing it off via the pedal helps. Especially stuff like aluminium or stainless.

Ok. The main time I've wanted finer control ... or maybe "on the fly" control is a more appropriate term, is actually when I want LESS amps rather then more. When I come to the edge of the material I'd really like to be able to back things down a bit as I think it would be easier to finish the weld nicely. As it is it's all a bit abrupt and as a result of feedback here now I know what I'm looking at and definitely see craters at the end of the welds where they finish at the edges.

My welder is pretty basic but I must say I've been very happy with it, it was one of the first bought in by TokenTools.com when he was just starting out. Considering how tiny it is, and it wasn't crazy expensive either, I think it's remarkable than any old schmuck like myself can pick up a torch and with about 30 minutes of trial and a lot of error start producing welds that are pretty darn good if I don't say so myself. Indeed I could have probably saved a lot of the error if I'd known that the torch has to be a lot closer to the work that I initially imagined, and just how important super clean surfaces are for the whole shebang to work properly. Sure it's only steel, nothing fancy as yet, but I've seen some god-awful stick welds out there, even in the hands of a relatively experience amateur welders. Chuffed is the word around here at the moment

Edit: I just had a look at the receipt and it cost me $650 delivered. At the time it seemed this welder was in a bit of a class of its own as most of the others in the cheaper end of the price range looked like junk. It doesn't have any ramp controls and only 2 frequencies (plus DC of course) but it seems like the next units up are a real jump in price and I wonder if I could ever justify their price tag many times what this one cost.

Do you have downslope control on your machine? Mine is a Token Tools INV200, it has a control for just about everything. I played around with the downslope for a while until I got it right. Now its set finishing up without a crater and not burning through is easy.

I used to stick weld too, never again. Mind you I did play around with the stick welding setting on my TIG machine before I got my argon bottle, and the welds were far superior to anything I ever managed with my old CIG transformer unit. Still, I havent used the stick facility since I got my argon, and I probably wont again unless I runt out of gas or something.

Originally Posted by 19brendan81

Do you have downslope control on your machine? Mine is a Token Tools INV200, it has a control for just about everything. I played around with the downslope for a while until I got it right. Now its set finishing up without a crater and not burning through is easy.

I used to stick weld too, never again. Mind you I did play around with the stick welding setting on my TIG machine before I got my argon bottle, and the welds were far superior to anything I ever managed with my old CIG transformer unit. Still, I havent used the stick facility since I got my argon, and I probably wont again unless I runt out of gas or something.

Oh you beat me to it. I was thinking about the machine as I was posting here, and what controls it has and remembered that yes indeed it does have a downslope control and could I use that? You read my mind as I had it set very low so will experiment with that next time. Thanks!

Gday
You could try this miller calculator and just convert the settings to metric http://www.millerwelds.com/resources...calculator.php
thanks caveman

G'day fellers, have just read about the problems that you seam to have in common. Craters at the end of the weld can be avoided by not moving away from the weld to quickly. The other cause of them is to much heat. So, turn amps down, move slower, then at the end of the weld add filler wire quickly as this helps cool things down . 'Pushing' the wire in helps with s/s if you have a gap/poor fit-up.
Hope this helps a bit, Col.