Has anyone ever heard of this?

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I just called Lincoln Electric support to find out why the wire speed for MIG welding .125 wall is so fast and virtually impossible to weld round tubing.The tech guy said most people use small stich welds on round tubing when welding .125 wall.  I told him that I was installing a roll cage and I felt that would not meet the tracks tech and not be a strong enough weld.  The guy then told me most people usually TIG round pipe for that application.Now I have heard of many chassis shops MIG welding roll cages.  Do you think Lincoln is trying to get too much out this this machine by increasing the wire speed?I am using a Lincoln Pro Mig 175.Thanks!  Mike
Reply:As I understand it some classes require the cage to be TIG welded. I believe it has to do with ensuring adequate penetration. You can weld a bead that looks real good on the surface but has little or no penetration. That's pretty hard to do with TIG. It can be done but is much easier to weld it correctly. I do agree that I would rather weld round pipe/tubing with a TIG setup. Infinite wire feed control manually and infinite(almost) amp control with a foot pedal.
Reply:Wat do you think about using FCAW to weld the roll cage?  IT is much slower and has a lot of heat for good penetration.
Reply:Go over to the Miller Ask Andy forum and ask your questionhttp://www.millermotorsports.com/mbo....php?forumid=3I believe most NEXTEL CUP cages are MIG with just a couple of teams doing TIG.If you get into the top fuel, funny car and pro mod NHRA classes then they require chrome molly tubing which in itself then requires TIG.It all depends on your sanctioning body and what class you want to run in as to what kind of tubing is needed and hence the welding requirements.You can usually run chrome molly in the lower classes to save weight (smaller wall tubing since it is a lot stronger compared to same size mild steel tubing).Hobbiest hack
Reply:you will NOT pass tech if you use FCAW.  Also if you are using a kit, most specificly say not to use flux core wire.check out: http://www.cachassisworks.com/HowTo/HowTo-005_web.pdf
Reply:I regularly am welding handrail which is two inch diameter and about 1/8th thick.  We use .035 S6 wire and a mixed gas.  You have to wind your arm and gun around the joint before you start.  Going completely around is difficult but going over half way around is quite easy.  You should practice a dry run to make sure you can move fast enough and not get hung up.  Keep all your scraps to practice on.  Generally you want your heat and speed up to get a good tie in.  You do not require a massive fillet on 1/8th wall.
Reply:Are you using a a drag angle?  And do you use any kind of weave pattern or small circles?Thanks!
Reply:When running hard wire you use a leading angle (push)  Some people are straight on but never dragging.  Dragging is for stick and flux core.  I am using 26 to 28 volts and running in spray.  The wire is turned right up.  The puddle is large enough that you don't have to weave much at all unless you are a bit off the joint line.
Reply:I have read a lot of different thing about the push -vs- pull with mig.  The most I could come up with is that the push method will have less penetration.Now if you are welding verticle on round tubing do you start from the bottom and push upwards?  I have read about people using the drag for verticle MIG welding.Thanks,Mike
Reply:If your wire is not at the leading edge of the puddle your penetration goes down.  You end up putting your arc into the body of the puddle rather than at the root of the joint if you drag with hard wire.  ( build up increases)Vertical up will give you the correct bead shape and penetration.  In vertical up you must use short circuit transfer.  Voltage would be down around 18 to 22.  Vertical down is very easy to do but you cannot deposit very much material and you risk cold lap.  The bead will look great but one side will just sitting against the parent metal.  I have lost count of the many times I have seen cold lap on vertical downs.  Sometimes it becomes visible when you put paint to the item.  For trouble free welds I recommend welding on the flat or horizontal.Also you might have noticed that vertical down beads usually are concave on profile.  That is a no no.  the only use for a concave profile that I know of is for the inside corner of chutes were the customer does not want material hanging up in the corners.
Reply:Lotechman, I really appreciate all your help and effort in explaing to me the differences. I am some what new to welding, but MIG seems a lot diferent to me than FCAW which I can do pretty good.  I am asking a lot of questions because I need to weld this roll cage into my car but will not attempted it until I am sure what is the correct way.How do I know if I am short circuit transfer?  And with the verticle up I sould use a push with about 10 deg. upward angle?
Reply:You likely don't have a voltmeter on your 175 but you can rig up a meter if you have a multimeter. ( ten dolllar cheapy will do)   Hook it between the work and the hot lead at your feeder.  You have to look at the voltage when running or you run the gun while looking at the meter.Your wire feed speed is your amperage adjustment ( heat)  The voltage adjustment usually is called something else like range control or somesuch.  At the lower settings you will hear a stacatto sound.  The wire runs out shorts on the work then burns off rapidly. ( short circuit transfer)  At a higher level of voltage globular transfer takes place.  The arc sound is different ... more violent than the small regular bacon frying sound of short circuit.  (more spatter)  If you have less than 20 percent carbon dioxide in your mix some power supplies allow you to increase voltage into spray transfer.  The arc is just a soft hum with the occasional spitting sound.  There is virtually no spatter.  Penetration is a bit less but deposition rate is high.  Spray starts around 26 volts.  At work I am up around 30 volts on the older machines and 28 on the newer ones with digital display. Spray is flat or horizontal only.
Reply:malich:I looked at the specs for the lincoln 175.  You are not going to get out of short circuit transfer very easily.  The operating voltage is around 20 volts which will not get you into globular transfer.  You are going have to rely on running short circut transfer.  that means you will have to do a deliberate weave between both parts of your weld joints in order to ensure proper fusion no matter what position.  I have a Miller 250 clone and can just reach the beginnings of spray transfer.
Reply:in level 'a' welding for CWB (canadian welding bureau) you do all root passes with tig and fill and cap passes with either mig or stick
Reply:"A" level is a provincial certification, while Canadian Welding Bureau tests vary according to the application and what procedures are being tested.  Most of the "A" level exercises concentrate on TIG roots and other processes to fill as you mentioned.  You don't even need a "C" level certification to do a CWB test if your employer sponsors you.
Reply:ya thatz true
Reply:If you are trying to turn your feed speed all the way down and still seems too fast you may consider a smaller wire size if your using .035 drop down to .023 this should help and be fine for the 1/8 " wall tubing you are welding. Just a suggestion.
Reply:See I dont understand y'all mig folks.  I think someone is all full of sheep sheet.  See Ive always been told one how hot this mig thing is.  It is easier to weld, its faster, its more productive, you can do the thinner stuff and the thicker stuff, unlike with stick which is limited to >= 1/8".   Yet when I hear something silly like this,  I have routinely welded 16 ga. galv pipe with a 6010 stick rod.  Ive done it on 1/8" a lot too!   I admit its a little tougher for me to do it this way than with a mig cause if you burn a hole with that 5p your kinda up stinky creek.  But its doable.  On a really small pipe its impossible, atleast for me to wrap it around with one solide pass cause of the restraints of my arm movement.  But thats never bothered me.  make it in two passes IM ok with that.  I just plan on welding one pass just a tad bit over half way.  Then the secondary pass should cover just half.  Makes it look real pro like if you do it evenly.  Otherwise I dont see what possibly these fellers are talking about, mig not doing 1/8" pipe.  If a country boy can whip out hhis stinger and do 1/16" why cant someone mig 1/8"?    Perhaps this is the great question??  The truth is out there somewhere!haha...its late...g'nihgt guysCHRIS
Reply:Can i get an amen!Chris I have heard that crap about not being able to weld light gauge materials with a stick all my life.  Hell I have even had my clients tell me they wanted it wire welded because they "knew" it was a better weld for thin stuff.  I've spent the past two days in a peanut combine basket welding 16ga sheet metal to expanded metal and using a 3/32 6013 with no problems. I often wonder who these people are that come up with some of these regulations, and ideas.  As alot of us already know it has alot more to do with who welded it than it does what its welded with. also malich, a good friend of mine builds alot of drag cars and welds everything with a lincoln 175 plus I know he is using .030 wire.  Give me a day or so and I will ask him what kind of settings he is running on his cages and I will let you know.  ~JacksonI'm a Lover, Fighter, Wild horse Rider, and a pretty good welding man......
Reply:Most regulation come from a negotiation.  They are not based on what is possible but rules of thumb that are easy to remember.  Folks should keep in mind that stick was around welding things since before the turn of the last century.  The "modern" stick welder is practically unchanged from those built in the 1930s.  Thin sheet metal was also around long before mig.  It got welded.Smithboy...if it ain't broke, you ain't tryin'.
Reply:Amen!
Reply:See I dont understand y'all mig folks.
Reply:Well I have done both and have no problem welding light stuff with stick. Stick welding is fine for a lot of things. Mig has advantages that stick just can not compete with. For example I weld on 39' trailers that cosmetic looks count on the exterior. Starts and stops are frowned upon to say the least. With mig you can weld 39' with out stopping you can not do that with sticks even if it was allowed it would take too long. Also when it comes to welding Aluminum stick does not even compare. I advise not to use sticks for aluminum unless it is just around the house. All professional aluminum welders use MIg or Tig. Even Tig can not compete when it comes to welding 160' of weld in an hour and a half and thats the expected time for completion in the mfg. shop I work in. Before the flames get started I would like to say I have great respect for the stick welding process and welders who make a living with it. My best friend went through the steel workers union about 25 years ago. He is one of the best all around welders I know and the best stick welder I have ever met. I have learned loads from talking and working beside him. But even he will admit migs faster.
Reply:Thanks RT.  I agree with what you are saying.  As far as flaming, if your referring to negative feed back I say whoever is the perfect welder may throw the first grinding stone.  I agree with what you are saying though whole heartedly.  My complain with mig people is less with alum(which Ive little experience) and more with mild steel.  Ive been in to many shops with people who justify the mig on all these reasons I listed off, like the thinner steel and all this.  Yet Ive rarely seen less than a 1/16" used, and although I agree with the speed issue I dont think mig is any purtier than stick.  Now that can vary course cause if your good enough to weld 39' wihtout stopping I guess your a god in my books.  I personally cant do it.  So i just learned to make my starts and stops look as uniform and flow together as best as I can.  But for me the stick is easier to do this than the mig.  Only draw back really is I can go a tad longer with mig than I can wtih sticks.   So mig does reduce the number of stop starts I do.  I also hear that stick isnt as strong as mig.  Which I say is wrong. Oh, and my claim that stick is as pretty as mig, its more got to do with the user than the process.  Stick has a slag on the outside of the weld. Sure it needs cleaning.  But a cleaned weld looks as good as any mig if the user can weld good.  Course Ive seen some really crappy mig welds, and some really crappy stick welds too.  Its all user ability and what your comfortable with.  I would really love tryin out your alum wire feed Robby.  Ive done the Tig and its great.   Tried the spoolgun once, I dont know  lol....kinda looked about as bad as my stick alum.   So I aint got much faith in it yet.  But I'll take your word on it as your obviously making a living building nice size trailers with it.  Anyway, enough of my ramblins. y'all take care and lets keep it clean in here boys, I know I got this mudslingin going stick vs mig but we gotta keep the mud clean...Take care CHRIS
Reply:Tx as far as stick being stronger. I would have to agree with you. When doing trailer repair work we have always kept a stick stinger and 7018 lo hi rods for times when steel chassis or suspensions start to crack. the best way we have found you stop the cracking is to arc gouge the crack deep and weld uphill with the 7018 stick. Nothing but nothing works as well in these situations. 7018 if I'm not mistaken has 10,000 pounds more tinsel strength than common hard wire for mild steel mig work but I am not sure that this is a fact but think I remember being told that before. Truck drivers rely on us to stop the cracks before DOT stops them from running the trailer on the roads. Stick is best there. And yes I have seen some very pretty stick welds. I will agree with that. Thanx for not taking me to the mat over my opinions just calling it as I see it.Robby, we all got opinions.  some are good, some are bad.  Some are better and some are worse.  In a place like this its hard to prove yourself before making statements, so our opinions are the only thing that we can prove ourselves on.  If were afraid to voice our opinions due to fear of ridicule the best info will never be released.  I think a good debate is good for users who arent experienced in different processes as in a debate of two processes you get the very best of both, and usually the negs too.   I can stand here and tell people all day how great stick is, but until you challenge it with the exceptions many folks wont know.  But apon reading they can make a judgement of their own.  Course it helps to debate with a feller who apparently can walk the walk.  About the 10k tensile more than mig,  hmm i dont know.  Im not an expert but i thought er70s wire had the same tensile as the 7018, vs say a 6010 which has 10k less tensile than 7018.   I do know the 7018 has a very low diffusable hydrogen count.  Dont quote me, but i believe this is the key to the added strength.  But with anything Im no metallurgist so I really dont know.  Anyway, I got another Q for ya, any experience welding alum tig without a remote?  My bobcat can weld ac with an hf but no 14 pin=no remote.  I know its possible, just wondering how practical it is.  Well thanks for your input.Chris