Hard to TIG Steel ?

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Are there steel alloys that are harder to TIG then others? I went to the local steel yard and asked for some steel topractice TIG on .. I have gotten steel from him before .. Only this was different then the usualt steel , but still looked likegood ole steel to me .. not galvanized or anything .. So I get some outta the scrap bin .. ask him how much he wants .. and give him like 5 bucks .. and go him happy .. Funny thing though? After I gave him the five .. he looked over and said " TIG huh? " Now he knows I MIG .. and I figured he was just curious thatnow I am trying to TIG ... but then when I got it home .. and tried toTIG It ..  wow .. hard to heat .. weld pool looked funny ... No I did only wipe it off ..  my mistake I know .. but still it seemed different .Which is what brings me to my question ..  Once it cools .. I'll brush it off and take pictures of it TIG'd and not .. and post them .. Any ideas pop into anyones mind at this point ?? I once heard the phrase "oil impregnated " cant remember if it was in regardsto steel or not .. Randy
Reply:ahhh post and we'll see whats up..the best thing to learn tig with is stainless steel 300 series..you can fuse it all day and learn the method of heat before ever having to add filler.. thats a whole 'nother trick......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:Oil impregnated would be oil lite bushings made of brass, also graphite impregnated. As for welding steel to be different between the grades, I don't know. SorryTony"Wherever you go....there you are"
Reply:I brushed it off and was looking at the welds.. and they are undercut .. and then it dawned on me where I have seen this kind of metal before.. at least by the appearance .. and thats muffler pipe material .. only in this case its thicker and not pipe ..  i'll take some pictures ..
Reply:Ok .. heres a piece of the metal ..Is steel with a higher carbon content harder to TIG? Attached Images
Reply:Originally Posted by Lanmanb4Ok .. heres a piece of the metal ..Is steel with a higher carbon content harder to TIG?
Reply:You are lookin a piece of that steel ..  Hey could be I just need to clean / brush it better .. But it still make me wonder about whether different grades of steel mightbe tougher to TIG then others .. Besides I am trying to get the prize for posting useless , meaningless questions .. LOL ..
Reply:Besides I am trying to get the prize for posting useless , meaningless questions .. LOL ..i'm afraid you have a ways to go my friend... ...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:That pic looks like standard ol' hot rolled steel....welds like shnit with the scale still on it. It will undercut badly and give very inconsistent beads if you leave it on...which is what happened to you.Either grind of the scale or next time you go to the steel yard, ask them if they have either cold rolled steel or hot rolled P&O(pickled and oiled) in their scrap bin. Those have no scale and will weld great with very little surface prep.BTW, the "muffler pipe" you are talking about is usually aluminized tubing. That piece looks too dark to be aluminized.http://all-a-cart.comWelding Cart Kits and accessories
Reply:I have tig welded a lot of hot rolled steel with the scale on it and didn't have much trouble with it.  I just weld it quick and use a good filler rod.  I think where you can get in trouble is to linger too long.  Also just fusing it can cause bubbles.  Once it is contaminated, you gotta grind it all out and start again.  When I really want it nice, I clean off the scale with murietic acid and rinse well.
Reply:Steel with a higher carbon content should go through a normalization process. The higher the carbon content, the more brittle it will get with the heat. That is why steels like D2 L6 and such are used for cutting blades and not recommended to be welded on unless they have gone through some preheat/post-heat process. Has anyone ever seen a die break after being welded without pre/post heating? Ugly!!!!!!Tony"Wherever you go....there you are"
Reply:yep i would say its the scale from the hot roled steel, hit it with a flap disk till its nice and shiny and it will weld real nice. im not saying you cant weld threw it but if you are new, clean it off and try again. it will weld sweet. big difference between MIG and TIG , you just gotta be clean to TIG. any thing you TIG should be clean and shiny. flap disk the heck out of it hit it with some asitone and go to town. summer is here, plant a tree for mother earth. if you dont have time or space, sponcer some one else to plant one for you.feel free to shoot me a PM or e-mail me at [email][email protected] i got lots of time.
Reply:ok .. will give that a try ... and see how it goes .. Thanks for all the nice info ..
Reply:Well ... really quickly this evening .. I took a piece of that alleged hot rolled steel . and milled the surface smooth and took off more then enough .  prolly like .025" worth .. Then I ran 3 short TIG beads .. Took a picture after .. Another interesting thing about this steel .. is the heat does notconduct along the piece of steel anything like the other pieces I have .. I wonder if a different amount of thermal conduction is an attribute of hotrolled steel as well ??  Thoughts .?? It didnt undercut this time .. and it did seem to flow better .I have another question .. I TIG left handed .. and I have been , up till this last session, TIG'n from left to right.But tonite ..  due to where I set this up at quickly .. I TIG'd from foward to back , uhmm towards me .. filler coming in from the right .. Is this ok? Anyone else ever do it this way ? I like how it felt but wasntsure if it was acceptable ..   Comments ?? Thanks .. Randy Attached ImagesLast edited by Lanmanb4; 08-08-2006 at 09:29 PM.
Reply:hot rolled dont turn blue... not like that...tool steel will however..take a file to it and see what happens......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:whatever way your comfortable with is whats ok for you...allways tig twards you never away.....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:ok will do .. and I think the flash might have helped bring that color out a little more then it truly was ..  Would / could tool steel be in a " channel " shape ??? Oh .. not sure if this helps .. but when I milled it .. the surface waspretty darn shiney ... and the scarf was quite hot ... ( hope that was the right word for the pieces of metal that come flying off when you mill it ) Randy
Reply:well its not hotrolled.. its some sort of alloy for sure..tool steel can come any way you want it..but it will cost ya...still looks like either A-2 or oil hardining tool steel......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:Well if it is , then maybe I should stop wasting it with welding practice ..  If I have a hardness tester .. I could always put a piece in the kiln and fire it up and then let it cool by air and do a piece and dunk it in oil ..  see if they get harder .. LOL ..
Reply:Originally Posted by Lanmanb4Well if it is , then maybe I should stop wasting it with welding practice ..  If I have a hardness tester .. I could always put a piece in the kiln and fire it up and then let it cool by air and do a piece and dunk it in oil ..  see if they get harder .. LOL ..
Reply:Well, there goes my theory!!! http://all-a-cart.comWelding Cart Kits and accessories
Reply:Hot rolled that has the scale removed will turn blue.  The color is the result of oxides formed during heating of the steel.  That shade of blue means the steel reached a temperature of about 600-650 degrees.  Any carbon steel will react similarly.
Reply:The cuttings from your mill is called swarf."SWARF    Fine metallic filings or shavings removed by a cutting tool."  American Heritage Dictionary.But I know nothing about relative tiggability (?) of steels.Have fun.awright
Reply:Originally Posted by awrightThe cuttings from your mill is called swarf."SWARF    Fine metallic filings or shavings removed by a cutting tool."  American Heritage Dictionary.But I know nothing about relative tiggability (?) of steels.Have fun.awright
Reply:Originally Posted by awrightThe cuttings from your mill is called swarf."SWARF    Fine metallic filings or shavings removed by a cutting tool."  American Heritage Dictionary.But I know nothing about relative tiggability (?) of steels.Have fun.awrightIm taking a wild guess here, but two things come IMMEDIATELY to mind.1.  That particular, lovely shade of blue....... I've seen that quite a few times, you never forget it......2.  The fact that the material doesn't conduct heat....... that's what really struck the nerve.I'm guessing you've got a piece of titanium there........That would also explain why the weld is nasty and undercut, you're dissimilar metal welding....Last edited by kbnit; 08-16-2006 at 08:53 PM.I r 2 a perfessional
Reply:its not titanium..thats battleship grey...i'm stickin' with tool steel...and another thing titanium is very lightweight..lanman..how heavy is that piece?? ...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 zapsterits not titanium..thats battleship grey...i'm stickin' with tool steel...and another thing titanium is very lightweight..lanman..how heavy is that piece?? ...zap!
Reply:hit it with a grinder and see what color it sparks, if it sparks white it is Ti, however I dont thik it is Ti either
Reply:Has anyone played with "free machining" or leaded steel before?  Here is how McMaster Carr describes it - "Ultra-Machinable 12L14 Carbon Steel The addition of lead, which acts as an internal lubricant, provides superior machining characteristics, including improved surface appearance. Commonly used for high-speed screw machine products.".  I first encountered it a while back when we had some parts made for a jig by a machine shop with our drawings calling for mild steel.  These parts had to be welded together, and all this stuff would do was undercut something fierce when tigging, and mig wouldn't stick to it.  Turns out they had used this free machining stuff which isn't very weldable.  It looks like plain old mild steel, but cuts great with machine tools.  I'm not saying that's what this steel in question is, but it hadn't been mentioned yet...Last edited by TubularFab; 08-17-2006 at 07:54 AM.
Reply:Panoz,The other free machining steel, 303, contains a large amount of sulphur, which aids in chip formation, but renders it darn near unweldable with GTAW.  But it won't turn blue like that, it turns a horrid shade of black.Hit that piece with a grinder, if it forms a "skin" that starts tearing your grinding wheel apart, its titanium, if not, you've got something wierd.  The lack of thermal conductivity was making me think of refractory metal, and combined with the blue color, that would work, but that's just my brain fart.I r 2 a perfessional
Reply:Well .. actually I went back down there today and begged for more scraps LOL .. and I did ask him .. and his reply was " hot rolled steel is the only thing we use here "  So I guess that answers it ..
Reply:Another theory shot to hell  I r 2 a perfessional
Reply:lanmanb4..if you come to the bash..bring a piece of that with you...we'll see about this.. ...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 PanozengHas anyone played with "free machining" or leaded steel before?  Here is how McMaster Carr describes it - "Ultra-Machinable 12L14 Carbon Steel The addition of lead, which acts as an internal lubricant, provides superior machining characteristics, including improved surface appearance. Commonly used for high-speed screw machine products.".  I first encountered it a while back when we had some parts made for a jig by a machine shop with our drawings calling for mild steel.  These parts had to be welded together, and all this stuff would do was undercut something fierce when tigging, and mig wouldn't stick to it.  Turns out they had used this free machining stuff which isn't very weldable.  It looks like plain old mild steel, but cuts great with machine tools.  I'm not saying that's what this steel in question is, but it hadn't been mentioned yet...
Reply:Originally Posted by zapsterlanmanb4..if you come to the bash..bring a piece of that with you...we'll see about this.. ...zap!