Really disappointing Stainless Tig results...

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Ok so let me first say that this is absolutely emberassing to post, but I need a LOT of help.  I went over to see if we could get an arc to start and at least make some puddles on some stainless pipes.  I had tried mild steel before and I managed to hold the arc quite well.  This, on the other hand, was really freakin hard!  I ground my tungsten to a very fine point, a medium point, and a blunt point to see if that was the issue.With the TIG amperage set to "4" which is what the brief manual said for 18 gauge, I managed to get a arc for about 2 secs at one point but it completely obliterated the work.  The machine is a Snap-On MM140SL.  The way it was setup was the ground was (+) and the torch was (-), is this right?  I thought I read something about it being the other way around.  We used pure argon @ ~20 cf though I tried from about 12 to 30 in stages and no luck and I didn't even bother trying to use filler wire yet.Help!  What's going on!?Also, the ground and the torch inputs look like they can simply be switched, will the machine do it?  My friend who owns it was worried it'd break but I have known that there are two types of DC TIG'ing... help guys!Here are the horrifying pics:Please guys give me input and realize I am completely new to TIG terms and theory though I have read a bunch.  I understand a lot, I just need laymans help!
Reply:ok now calm down..dont get discouraged... from the looks of the last pic it seems like the gas coverage is not there...and its still looks  "dirty"  your not touching the tungestion to the piece are you?the yellowish "ring" is the tell tale sign of contaminated tungeston..filler or base metal is on it...i know it ain't easy...but your learning..as far as your machine goes i have no clue..not up to speed with it   ...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:I scratch the surface for the arc start because its not got HF - I have no choice really.  How do I properly clean it up and why am I blowing huge holes through the work?  What size cup should I use?  I have a 7 on there.  What gas flow?Is it ok to use the ground positive and electrode negative?  Also, I am 2% thoriated and 100% argon, sound ok?
Reply:Is it ok to use the ground positive and electrode negative? Also, I am 2% thoriated and 100% argon, sound ok?try it just for laffs the other way..but the machine i used in the past was dc pos...or dc straight whatever you called it.. but ac is ac no matter how you look at iteverything else is ok....zap!Last edited by zapster; 07-21-2006 at 09:19 PM.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:zap s right looks like contaminated ,  and maybe too hot, you shouldn't burn through. try lower temp low an increase temp... clean with accetone, and a SS brush. the gas flow sounds ok at 20  ( i use 12-20) soimetimes a little more. first pic looked ok but burn through(too hot)  second  contaminated for sure. it best to have a few tung. ready to use because  you will dab the tip --ONCE contaminated change it,,, never try to use again till you clean it an make sure you get all the contamination off. i would try it at lower temp .. stainless is  tuff to learn but not that hard
Reply:it also may just be that your doing this with the "scratched off the flux" "wire" now arn't you...  hmmm herein lies the problem i believe...well i asked in another post how it worked...i guess we have our answer......zapI 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:I am not even trying to use the filler wire yet Zap just get an arc started.  Does it hurt me that I don't have a pedal and only have a button on the torch?
Reply:i'd have to say yes...a footpedal is a must with a tig machine...no footpedal..its just a fancy arc welder..i have no history with a one setting machine...can you get a footpedal?it makes life so much easier.....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:Looks like containation to me also....I have a few questions...1) are you sure you are welding stainless?  Could it be galvanized instead?  I just wanted to get that one out of the way, because in one of the pictures I see what looks like little tiny web-like hairs at the edge where you burned through...it's probably not galvanized cause that's the only place I see it...it's just a passing thought.  2) I have heard of folks getting bad (contaminated gas)...do you have access to a second tank to check that?3) could there be any leaks in the torch sucking air in?4) How much stick out do you have the tungsten at?  You might have it out too far and be lacking gas coverage.5) are you starting the gas before try to start the arc?  try a full 3 seconds of pre-flow before you strike the arc just to be on the safe side.6) I would back off on the amperage a lot and work up like prop-dr suggests.You can do it without a pedal, but it would be easier with one...without a pedal and you have a much narrower window of amps you can run with for the entire weld.  I have done some stainless (not a lot) without a pedal, and because of the bad things that happen to stainless when it's overheated, you have to be pretty close to the optimal amps right from the get-go...this means starting and finishing is tough.Last edited by smithboy; 07-21-2006 at 10:38 PM.Smithboy...if it ain't broke, you ain't tryin'.
Reply:It's contaminated. Clean, and the clean again. Lower the amperage. Start out with about 60 amps. Use a 3/32 electrode, the argon should be around 12cfm. Try with electrode negative and when you lift the tungston from the surface, don't wander off. Keep your elboes tightly tuck in or on the table or welding surface. Looks like you are wandering too much.Just my $.02.
Reply:As you were starting on the edge of the tube, you have to know that it will want to burn away very quickly!!! Try to start on the flat piece you were trying to weld to, and pull the puddle up to the tube. You have to work on that, and get quick about pulling it up, and adding necessary filler. I also agree that your settings sound right, but you need to get a sready hand to run the torch. I use a Miller 150 for SS repairs on boat railing/ towers. The thin wall stuff definitely will humble you. Hang in there, and post up your next attempts. BTW, great pics. Very easy to see!!!!!
Reply:Originally Posted by orphan68It's contaminated. Clean, and the clean again. Lower the amperage. Start out with about 60 amps. Use a 3/32 electrode, the argon should be around 12cfm. Try with electrode negative and when you lift the tungston from the surface, don't wander off. Keep your elboes tightly tuck in or on the table or welding surface. Looks like you are wandering too much.Just my $.02.
Reply:Also - how far away is the tip of the tungsten from the work when holding an arc?  With mild steel it seemed further, this SS I am like a hair off the work and I lose the arc.
Reply:Originally Posted by Jon KAlso - how far away is the tip of the tungsten from the work when holding an arc?  With mild steel it seemed further, this SS I am like a hair off the work and I lose the arc.
Reply:Originally Posted by RojodiabloCheck the contacts for the ground. Not a good ground, not a good arc!!!! If the arc closes out too fast, you need a touch more amps. For reference, I can carry 1/4" or even 5/16" arc lenght when shifting position with my maxstar 150. It obviously isn't welding well when I do that, but it holds on while I reposition myself.
Reply:Originally Posted by Jon KWOW that is ridiculous!  I ground to my work and I can't break away even 1/32" before losing it.  When I set the amps higher I blow through the piece!  Hrm I have to be doing something completely wrong if you've got over 1/4"!  What the heck...
Reply:Ok I must be doing something very wrong.Is paint thinner acetone?  Maybe I am doing that wrong.  Man - I wish someone were local and could just SHOW me how I should be doing this!
Reply:Originally Posted by Jon KOk I must be doing something very wrong.Is paint thinner acetone?  Maybe I am doing that wrong.  Man - I wish someone were local and could just SHOW me how I should be doing this!
Reply:Jon,First I would like to say I'm no expert but I do work on large Industrial laundry machinery. These machine are made of 316 Stainless Steel, are approx forty feet long, wash four thousand pounds of laundry per hour and cost approx $250,000.Although you can certainly weld most anything without an amperage control including Stainless Steel it is difficult. All you need is practice though. We are all spoiled by things such as Hi Freq and foot pedals.1. I think your polarity is backwards.There is no reason not to change the polarity of the torch it will not hurt the machine unless it's a  cheap piece of crap and it isn't.If the polarity is reversed then you will see your tungsten turn bright red and begin to melt. When set wrong the black ugly mess you have is one indicator.2. Try starting on this thin material around 40-50 amps.A 1/16" or 3/32" tungsten should be fine I would use a 1/16" 2% thoriated judgeing from the size of the tubing you are trying to weld. But I don't think it really matters.3. NEVER "Tap" the tungsten to the work it will surely stick....... You scratch start when not using Hi Frequency. Kind of like softly scratching a match. I always scratch in the direction of travel so I can lift the arc and just keep going in that direction.4. Although most everyone here may have more experience than me I need to point on thing that they are telling you that is wrong....In a perfect world you will have Hi Freq and a foot pedal or hand control on the torch to help get you started and you would never touch the tungsten to the base metal or puddle. I agree it is of utmost importance to keep your tungsten as clean as possible however remember when scratch starting you have already contaminated it a little bit before even starting to weld because you must touch the metal to start the arc. So my point is you always have a little bit of schmutze on the tungsten when using TIG and scratch starting.If your arc is uncontrollable and and you can't get it to go where you need it to then it is time to change tungstens for a freshly ground one.Sorry for the long windedness, I hope some of this helpsWashman
Reply:Jon,First I would like to say I'm no expert but I do work on large Industrial laundry machinery. These machine are made of 316 Stainless Steel, are approx forty feet long, wash four thousand pounds of laundry per hour and cost approx $250,000.Although you can certainly weld most anything without an amperage control including Stainless Steel it is difficult. All you need is practice though. We are all spoiled by things such as Hi Freq and foot pedals.1. I think your polarity is backwards.Are you sure the Argon flowing? Can you hear it? Be sure the torch valve is open.There is no reason not to change the polarity of the torch it will not hurt the machine unless it's a  cheap piece of crap and it isn't.If the polarity is reversed then you will see your tungsten turn bright red and begin to melt. When set wrong the black ugly mess you have is one indicator.2. Try starting on this thin material around 40-50 amps.A 1/16" or 3/32" tungsten should be fine I would use a 1/16" 2% thoriated judgeing from the size of the tubing you are trying to weld. But I don't think it really matters.3. NEVER "Tap" the tungsten to the work it will surely stick....... You scratch start when not using Hi Frequency. Kind of like softly scratching a match. I always scratch in the direction of travel so I can lift the arc and just keep going in that direction.4. Although most everyone here may have more experience than me I need to point on thing that they are telling you that is wrong....In a perfect world you will have Hi Freq and a foot pedal or hand control on the torch to help get you started and you would never touch the tungsten to the base metal or puddle. I agree it is of utmost importance to keep your tungsten as clean as possible however remember when scratch starting you have already contaminated it a little bit before even starting to weld because you must touch the metal to start the arc. So my point is you always have a little bit of schmutze on the tungsten when using TIG and scratch starting.If your arc is uncontrollable and and you can't get it to go where you need it to then it is time to change tungstens for a freshly ground one.Sorry for the long windedness, I hope some of this helpsWashman
Reply:I'm sure Zap or Mac will corect me if I'm wrong but, When you scratch-start, the tungsten doesn't get contaminated because it is still cold (and the material you are scratching it against is still cold)Unless of course your trying to scratch an arc in a pile of grease or some wet paint.Patrick
Reply:Originally Posted by Sober_PollockI'm sure Zap or Mac will corect me if I'm wrong but, When you scratch-start, the tungsten doesn't get contaminated because it is still cold (and the material you are scratching it against is still cold)Unless of course your trying to scratch an arc in a pile of grease or some wet paint.
Reply:sometimes i "scratch start"...but when i do i always tap the pedal FIRST before i touch the tungestion..to get the gas flow happening BEFORE i go to it...i really dont "scratch" it..i just GENTLY "tap" it in the work and proceed from there...next week after i learn my new machine i'll post pics if how i do it..anyone ever try pics thru a mask?i'm gonna try it with the camera on a tri-pod and a shaded lenz in front of it..20 sec delay on the camera and we'll be good to go......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 zapsteri'd have to say yes...a footpedal is a must with a tig machine...no footpedal..its just a fancy arc welder..i have no history with a one setting machine...can you get a footpedal?it makes life so much easier.....zap!
Reply:I tried to take pic behind a hood once and I really couldn't see it to good, maybe you got a better camera though. I used my phone, it take pretty good pics though 1.3 mp.  I wa expecting it to turn out like the ones they show on tv.DewayneDixieland WeldingMM350PLincoln 100Some torchesOther misc. toolsHey guys - guess what the problem was?  The thing that holds the tungten from the back, with the slit in it for pressure, well uh yeah I put that in backwards so no gas or very little gas was making its way to the tip.  I flipped it around, tightened the back cap up, and she's welding.  Don't I feel dumb!I ain't pretty with it, but we're getting somewhere.
Reply:dont feel bad..i used to put the collets in upside down and wonderd why the tungestion would always work its way out..... ...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.