I have been welding for 10 uears now off and on and steadily for the last 3, I have just recently wandered in to TIG territory and it's been a while since any formal instruction and my welds look like crap. Not the bead appearance so much as the color and "texture". I will attach a few photos I took this morning. I am using a 3/32 2% thoriated electrode, hot rolled steel with the mill scale sanded down to shiny bright metal, 308L stainless filler, standard #6 cup, 17 series torch. Material thickness is 1/8 and I'm running 90 amps, pure argon at 30 cfh. This is just a few stringers on some scrap. If anyone can spot where I went wrong then by all means feel free to let me know.
Prepped material
20140919_074503.jpg (31.38 KiB) Viewed 860 times
Torch
20140919_074531.jpg (27.32 KiB) Viewed 860 times
Close up to show electrode tip and stickout
20140919_074525.jpg (30.15 KiB) Viewed 860 times
Rod used
20140919_080058.jpg (31.66 KiB) Viewed 860 times
Machine settings
20140919_074546.jpg (32.54 KiB) Viewed 860 times
End result
20140919_080020.jpg (30.71 KiB) Viewed 860 times
Do it right the first time, or don't do it at all!
30 is way too high man. You're double at least what you should be. Too much argon is just as bad as not enough. Turn it down to 10-15 cfh and try again. Your not running a #16 or #18 cup that you're trying to fill, that #6 is 3/8" at the end of the nozzle.
No problem man. Like I said, you actually create turbulence at that point, and can pull atmosphere in when it creates the low pressure zones as it swirls.
Hotter and faster will help the bead flow out. You want a nice even width with the toes fully wetted into the base metal. That's really hard to do when running on the cold side. I'd personally set the machine at about 130 amps and work the pedal. You'll outrun the coverage of a regular collet body and #6 cup though, so expect some gray.
zank wrote:Hotter and faster will help the bead flow out. You want a nice even width with the toes fully wetted into the base metal. That's really hard to do when running on the cold side. I'd personally set the machine at about 130 amps and work the pedal. You'll outrun the coverage of a regular collet body and #6 cup though, so expect some gray.
+1
I agree with Zank - also, out of curiosity, why are you using 308 stainless rods on mild steel?
If you have one, you can drop down to a 1/16" tungsten - you're not running enough amps to need the 3/32"
Attachments
image.jpg (63.66 KiB) Viewed 799 times
Dave J.
Beware of false knowledge; it is more dangerous than ignorance. ~George Bernard Shaw~
Syncro 350
Invertec v250-s
Thermal Arc 161 and 300
MM210
Dialarc
Tried being normal once, didn't take....I think it was a Tuesday.
Also, you need to practice to hold a tight (~0.050") arc. Shaky hands and holding the tungsten like a Roman Candle (far, far away, lol) will get you no where fast. Prop so you can always get a clear view of the tip of the tungsten. If you can't see the tip of the tungsten, you can't see arc length to the work piece, simple as that.
You may want to check out Hobart School of Welding book store on line. They have the knowledge (no doubt about it) for sale to one and all. When I got my MIG machine I bought their GMAW (MIG) book and a calculator card for each Mig, Tig and, Stick. Bought a Tig machine two weeks ago. One week ago I bought their GTAW (TIG) book. Their shipping cost is stupid high, but the the product is worth it- imho. Miller has a good GTAW booklet on their site too. Its a pdf and, goes into variables for material, electrode, gas, power, etc.
With your gas set at 30, didn't you notice the puddle begin blown around? That was my experience when trying to fix the bead with gas flow. Setting gas to about 15 is solving the gas variable for me with .120 inch thk cold rolled steel. The heat thing was dogging me too. It can be solved by getting the item being welded up of the bench. Get an air gap below what you're welding and you'll have better control of the heat. The bead formation and movement becomes more predictable. Hope this helps.
