I was a certified arc welder for years. Used to chase the nukes. I have been MIG welding at home for almost as long as I have been arc welding (53 years now). Even some oxy/ace torch welding. Last week my son and I split a TIG machine. My only TIG experience was welding a lot of square tube aluminum handrail. I was pretty decent at it, but that was after someone set up the machine for me and it was just repetitive 1-1/2" long flat welds. And that was 35 years ago!!! My son has very little welding experience at all. So this is a learning experience for both of us. First thing I learned was that these almost 70 year old hands aren't as steady as those 35 year old hands were. I'm able to make some pretty decent welds, but still pretty inconsistent. Anyway I've been working on this cart setup with the TIG. A buddy gave me this nice 18" x 24" stainless steel cabinet with drawer I made a dolly with casters for the cabinet and argon bottle. Then I made some rod holders for the different kinds of rod. I made a handle from 304 .065 x 3/4" SS tube to weld to the cabinet to steer the cart. The stainless welded OK for a beginner, fuse welded. Then I clamped it to the stainless cabinet and tried to weld them together. WOW!! The arc turned colors, sparks started spitting. Immediately contaminated the tungsten. Uncontrollable arc. No way to weld to the cabinet stainless. At first I thought the new welder has effed up. Tested on a piece of 304 SS. It worked perfectly. I tried again to run a flat bead on an in conspicuous place. Same thing. Yes, I cleaned the area on the old stainless cabinet before trying to weld. I don't know what series stainless the cabinet is, but it is nice shiny, rust free stainless. Best I can describe it is, it's kinda like MIG welding without the gas turned on. Very strange. Anybody know what going on? I ain't showing any of my welds! Right now they're good enough for a TIG cart, but I'm not TIG welding on my car for a while yet. Some of you guys are absolute artists.
SS contains chromium and it oxidizes badly when welded in unshielded conditions. When welding tubing, and shapes that can be enclosed, purists "backpurge" with argon to keep the oxygen out. When welding SS exhaust pipes, I use Solar Flux B. I make a paste and put it on the inside of the tube. It makes the welds nice and smooth inside and out. It is not for food grade welding, however. (Obviously) You are experiencing oxidation of the chromium, I believe. Somehow, you have to either protect both sides of the weld from oxidizing. Either provide a "backpurge" or use the flux. Thats my .02 dollars worth.
might be brushed chrome or something, rather than stainless. Or just a really crappy grade of stainless.
I have had my own issues with the different types of stainless, so I can't offer any personal advice, except to tell you to look up the youtube articles on stainless by weldingtipsandtricks. Here is a link, this guy is fantastic. Bob
Magnet doesn't stick. I hit it with an 80 grit flap wheel before trying to weld it, so I don't think it is oxidation. I've seen the pipefitters back purging their welds on the nukes a lot. No way to back purge here, but I don't think it should be needed in this case.
I've got to agree with the guys who say that it probably isn't stainless or it is a poor quality of stainless. If I can catch up with a buddy of mine who is one of the most knowledgeable stainless welders I know I'll ask him. Need to swing by and see if I can catch him.
Make sure you have a good clean ground to both pieces that your welding together and the closer to the arc, the better.
Then, buy some Solar Flux Type B and apply it to the backside of the weld. If you're going to be welding SS trim and exhaust tubing, it will be money well spent.
That cart probably isn’t stainless. There are many different coated steels that look like stainless but aren’t.
Yeah, the description sounds like the first time I tried to tig brass until I learned to sneak up on it very very carefully. Something on, or in the metal that doesnt like the arc. but just in case its not the metal... gas coverage turned up enough? argon is heavier than atmosphere. tigging on a bench or table is easy to cover with not much flow. Tig on a vertical wall, and you get argon spilling down the wall. add to that a "chimney" effect of the hot area making an air updraft, and you possibly have two garden hoses spilling and swirling a bad mix where you are working. maybe simply turning up the gas? When you get used to welding aluminum, you have to keep pouring in the heat as the aluminum quickly conducts it away. Stainless is opposite. The heat stays put. You have to try hard not to put heat into it because it will stay there and climb climb climb. just a guess.... maybe thin sheetmetal getting cooked while the gas coverage is being carried away from the hot area. ??? make sure the gun keeps blowing the shield gas to protect the hot metal from air as it cools after the arc is gone. Stainless is very sensitive to air when its hot. If you're used to aluminum, where you can cut away much sooner you might be cutting away from shielding the hot metal with the gas while its still too sensitive to reacting with the air. ? I did that too. Stainless stays much hotter for much longer, and it is much easier to tarnish and cook if you dont practice extreme patience. Do not use "aluminum habits" on stainless. I know it's a stupid question, but you're not forgetting to switch away from ac, and you are using electrode neg, right? sorry for asking, but I had to. sometimes letting the tungsten get too hot or dirty can make crazy flashes and junk in the weld. try a larger electrode if it gets too red too quickly? I have no idea whether any of this was helpful, but that's what I got. HAVE FUN!! WHY BE ORDINARY ?
I just did this for practice yesterday, using a cutting from a refridge door skin, a small bending brake for the top and bottom "legs" or flanges, a 2 inch pipe in a vise to bend the curve, and a saw, then a file, and sanding disc to level and smooth the welds. invisible!!! The only thing I had to protect the back of the thin stainless was some crumpled aluminum foil with a football inflation needle stuck in the foil cover to fill the foil wrinkles with argon. That was enough to protect the backside. A little filing the welds down, a grind or two, then a 4-1/2 angle grinder with a flap disc, and then hand sand. I am very new at this, but when you get past the "what the hell is wrong now" part it gets to be fun again hmmm, maybe if I add more refrigerator door skin, I can make a cool bumper cover skin for a truck or something. or a cool polished radiator shroud, or or WHY BE ORDINARY ?
Now I can't stop posting ! Here is my backpurge stainless protector made from a football inflation needle. I wad up some aluminum foil, tape it on back (of course the tape is a little distance from the heat) then I push the argon needle under the foil to keep the air from ruining the stainless. the next picture is my grounding rig because I dont believe in the common "throw it on the table and it will ground itself" at what price? a dozen amps? three volts? will it be the same when you slide it? or drop on another piece? will it have the same resistance? a wavering spark for a second then a good contact? crap, JUST GROUND IT! ok, now the pics. Should I post these in the Homemade Tools thread, or are these not qualifiers? The wire clamp screw was missing, so I used a pipe thread elbow and nipple to screw in and clamp the wire. Now it can use the pipe to steady the clamp as a part holder too. I ground everyyhing instead of trusting dirt and luck. I hope I've helped a little. WHY BE ORDINARY ?
Sounds like a reaction to some kind of plating or as others have said, a crappy stainless alloy. Good luck. That’s a nice T coupe in the background, share some pictures with us! Sent from my iPad using The H.A.M.B. mobile app
The Jalopy Journal
