Tig welding stainless ? Horrible start.

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Today was my first attempt at welding stainless with TIG. I've got many years of tig experience on carbon steel but no stainless until today. What a mess, I couldn't get it for the life of me. Is it just that much more touchy then mild steel? The material was 304 stainless 1/4" plate and I used argon for gas, 2% thoriated tungsten and a miller 180SD syncrowave TIG box at all different amperages. Question, even tho I was using 304 filler rod, it is possible it was marked wrong and could have been 309 or 316 filler rod. would this cause nasty issues with puddle flow etc ? Does the tungsten have to be prepared different then when welding mild steel? Does the raw stainless need to be prepared first with grinding etc? Like is there some type of oxide finish or something?I just dont get it, it was so frustrating.thxs.DJN
Reply:SS has to be very clean, the word sterile comes to mind. It also should be backpurged, but with 1/4" plate I don't think it was causing the problems you (vaguely) describe. Brush it well with a SS brush and wipe it down good with acetone.Miller EconotigCutmaster 38Yes ma'am, that IS a screwdriver in my pocket!
Reply:ss  should puddle and flow nice....even fuse without filler...
Reply:Welcome to the forum.More info would be helpful. Exactly what issues were you having? Picts would be best along with as much info on what the settings you were using fro the different beads. The more info we have the easier it is for us to understand your problems and suggest solutions. Good luck.
Reply:You're probably pulling your wire out of the argon sheild, letting it get contaminated...then putting it back into the puddle.  That and poor heat control are the most common problems for people new to stainless.
Reply:Stainless seems pretty easy, but I don't tig much mild steel. I wonder if you are putting to much heat into it or moving to slow?Tim Beeker.
Reply:SS should weld easier than even mild steel, and the 309 or 316 filler should not pose any problems. Maybe not enough gas coverage or something? I don't scrub SS clean, I rarely even wipe it with acetone. It usually goes just fine. How about some pics??And then, after so much work...... you have it in your hand, and you look over to your side...... and the runner has run off. Leaving you holding the prize, wondering when the runner will return.
Reply:300 series SS has lower thermal conductivity than carbon steel. The same heat (amperage)  that you use on carbon will cause a puddle that stays hot for longer. During this time the puddle has more time to sag when welding out of position and it also may begin to oxidize on the surface because it is still hot when the argo shielding is gone. If you had good looking carbon beads, the manipulation required is similar. You may just need to turn it down some.Have a nice dayhttp://www.weldingdata.com/
Reply:3 rules for welding stainless steel1.  Clean it2.  Clean it3.  Clean it again.Wire brush the area to be welded and about 1/2 an inch away.  Wipe with acetone or isopropyl alcohol.  As was said already, keep the filler metal in the shield gas or you'll oxidize the end of your rod and it will want to ball up when you go to feed it in the puddle.  Stainless isn't all that hard to weld, if you can weld mild steel, you can weld SS.I r 2 a perfessional
Reply:Originally Posted by RojodiabloSS should weld easier than even mild steel, and the 309 or 316 filler should not pose any problems. Maybe not enough gas coverage or something? I don't scrub SS clean, I rarely even wipe it with acetone. It usually goes just fine. How about some pics??
Reply:Thanks everyone for the replies. I'm going to try again tomorrow morning and post some pics. Since I did zero metal prep before trying last time I'm guessing that's the problem forsure. Will post tomm,thx.DJN
Reply:The filler wire was probably 308. 308,309,316 are common.The diameter of the filler wire should be .045 for the 3/32 tungsten.The tungsten should be sharpened to a point simular to a pencil point.Weld it just as you would weld the steel.But it is best to weld a joint NOT just a bead on top of the flat plate.Try to cut the plate into two parts so you are welding a joint.Tack first of coarse.You will not be able to make the weld in ONE pass.It would take more than one pass on 1/4 inch plate.
Reply:No need to clean it unless there is visible dirt/grease on it.  Depending on the application and how you do it wire brushing stainless can do more harm than good.I think stainless runs much easier than mild, also using a 180SD.  Its a little on the low range, just set it to max and go heavy on the pedal.Have we all gone mad?
Reply:Clean stainless. Every one has their opinion. For most people that I know wiping with a solution would be saved for bench welding coupons. Unless as stated before, obvious dirt or grime. Just make sure that if you are using a flammable liquid to keep the cloths and liquid far from the welding table.One thing that I know for sure is that if your metal is dirty, you will definantly know pretty quickly once you strike an arc by either smoke, tungsten problems, or various other sights or sounds not normally present
Reply:While i agree with most that you don't need to go OCD with pre weld cleaning one important thing for someone new to stainless is to avoid using ANY abrasives that have been used previously on carbon steel- no wire brushes either unless they're stainless tooContaminating stainless with carbon steel won't effect the welding to any large degree but can lead to what appears to be 'rusting issues' once the part is in service. Differences compared to carbon steel... The chromium that gives stainless it's properties is extremely reactive at welding temps, forming oxides and carbides given the chance- leaving less to provide corrosion resistance. Stainless is a poor conductor of heat so less amps are required than for carbon steel (begin with 10% less). As well as poor thermal conductivity stainless has a high co-efficient of expansion making it more prone to distortion than carbonAs several others said problems are almost certain related to removing the end of the filler from within the gas shield and/or too much heat input. Contaminating the filler is easy to identify- run an autogenous (no filler used) weld- if it comes out cleaner then that's the issue.
Reply:hey man just clean it up,,you dont need acetone or any other liquids,,i make 100% x-ray welds all day everday,,hit it with a tiger disc lightly,,what cup size are you using,,bigger cups are good for alloys as you get more gas coverage,,10 or 12,,i pull my wire out of gas all the time welding pipe,,usually i drip all my alloys in,,so that isnt it either,unless you just get a blob on the end of your wire,,,your heat should start to melt stainless slow then get hotter on its own while moving down it,,if you start of hot on it you will be way hot before its over with,,one more thing,stick your tungsten out about an inch or so,with alot of gas to get good color in it,,,blue and gold,,,oh yeah 308,316,317 are just higher grades of stainless,and would actually look nicer than 304,,,,309 is carbon to ss,,gd luckgulf coast legend
Reply:Originally Posted by elmo....,i pull my wire out of gas all the time welding pipe,,usually i drip all my alloys in,,so that isnt it either,unless you just get a blob on the end of your wire,,
Reply:This the Internet and you will get a lot of at times differing opinions, I would like to add weight to ZTFabs comments they are spot on.  Originally Posted by ZTFabThat is an absolutely sure fire way to contaminate a SS weld. Keeping the filler rod in the shielding gas is crucial.
Reply:Originally Posted by ZTFabThat is an absolutely sure fire way to contaminate a SS weld. Keeping the filler rod in the shielding gas is crucial.What? Keeping the heat consistent is the key. Full and equal penetration. That's why TIG welders have a foot pedal.Are you kidding me? Maybe that works for pipe welding with a gas lens where you're working deep inside the root of a v-groove but not for welding plate in ambient air.
Reply:Originally Posted by elmoi dont have a foot pedal,,i weld in pipe racks and in boilers,,i throw my tungsten out about an inch for my cap,which is on the surface, same as plate,,if i weld a dummy leg on that is ss,,i do the same,,you wont contaminate your ss wire unless you let the metal ball up on the end of your wire,and then pull it away,,i'm a real tig welder bud,in the rack,not on a table,,ss,alloy 20,duplex,monel,inconel,chrome1 thru9,carbon,mirrors,left and right hand,,you test in a convection box then tell me how to weld,,in boilers we have to feed the wire for each other at times,,all 100% xrays,,if you use a bigger cup you get better gas coverage,period,and you can hang that tungsten out there for a pretty weld,,,golds and blues in it,,,and when i say pull the wire out,,i mean your drip it on,dab the wire into your arc,some falls off and you pull the wire away,,sweeping the dab across the weld zone,then repeat,,and words like ambient dont impress btw,,i work up in wind,so if you have a problem in stale (ambient) shop air,then lol on you
Reply:the guy said he has welded alot of carbon,,,welding ss isn't much different,,,as for the legend thing,,its a joke amonst friends,,,10 and 12 cups only,even on a 1" pipe,,i use a ten,,you always get better gas coverage with a bigger cup,,and even if you are just welding 2 plates together,,a ten is going to move easier than a 8 or 6,,now if he is doin some small intricate work,,than i can see a small cup,,,also with your tung out further you are goin to get better coverage on your weld,,and in my opinion your edges are goin to blend in real nice,,i didn't get smart *** untill a couple guys chimed in with quotes of mine,like i dont know my a$$ from a hole in the ground,,,i weld 12 hours a day most of the time,,so rest assured that i do,,advanced techniques always become the easiest,,,and the little tricks aren't for master welders,,they make anyones job easier,budgulf coast legend
Reply:Originally Posted by elmo10 and 12 cups only,even on a 1" pipe,,i use a ten,,you always get better gas coverage with a bigger cup,
Reply:I go along with what ZTFab and Engloid has to put fourth on this subject..All in agreement?...zap!I am not completely insane..Some parts are missing Professional Driver on a closed course....Do not attempt.Just because I'm a  dumbass don't mean that you can be too.So DON'T try any of this **** l do at home.
Reply:Originally Posted by EngloidI don't know where you're getting this stuff, but you seem to have forgotten that a larger cup requires more gas flow.  A larger cup doesn't mean better gas coverage, it means more gas coverage...which, without turning up your flowmeter, means that you may actually not get as good gas coverage..in fact it could be insufficient and cause problems.  For clarity, I believe you're referring to walking the cup, and its effect on the ease of travel.This isn't true at all.  The best coverage would be INSIDE the cup, or near the cup.  Lets say you have 30cfh flow, and a 4 second postflow.  Try that with 1/2" out of the cup, and with 1" out of the cup.  When trying each, you will find the tungsten will discolor much more at 1" out of the cup....because the coverage isn't as good there.
Reply:Have any pics of your work, elmo?http://all-a-cart.comWelding Cart Kits and accessoriesi'll get some,,,actually i helped blacksmith and put up the ss on the ut tower so it could reopen,,and keep the jumpers at bay,,i'll snap some of what i do in the next few days,,i think george bush comes after you for having a camera in the plants,lol,,but i'll get somegulf coast legend
Reply:Thanks, elmo.If I came across as harsh it is simply because we all know nothing about you. You have not posted an Introduction or any pics of your work. Your first post in the forum was on this subject. Think about it this way...if a new guy walked onto your jobsite tomorrow and started brashly talking about what and how to do things that seemed uncommon practice, how do you think it would be taken? Give us a little background to work with so we know where you're coming from.http://all-a-cart.comWelding Cart Kits and accessories