bad mig welds

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In the old days I used to complain about having to repair bad mud rod welds.  A mud rod is low penetration-fast-flow weld, E6013 and E 7014 are examples.But since everyone is using mig I get a ton more of welds that aren't.I was asked to estimate what it would cost to replace a bug shield on a brand new two car hauler.  They'd  butchered installing some twenty six or so gauge and I'd suggested aluminum diamond plate as a replacement.This is a brand new two car hauler, never hauled squat, sixty five hundred dollar trailer.Their good fortune is it rained before they had a chance to load it for a haul job.Check this out. Attached Imageslife is good
Reply:Those beads are on the gusset plate for the goose neck.  It's like that inside too. Attached Imageslife is good
Reply:Here's a shot of the tie down installation. Attached Imageslife is good
Reply:The builder has agreed to pick up the trailer and make all the welds good.And that's the way it should be.But he's lucky it rained before they put it into service.  Otherwise he could be looking at a pretty stiff bill when it all came apart at speed and under load.What happened here is obvious.  Someone was watching their puddle and trying to make a pretty weld.  They weren't  concentrating on making a good weld.  A good weld comes with metal melting together.The funny thing is most good welds look good.  And with a mig especially the best time to judge whether you're caulking or welding is when you're in the process.If the thought of something you've made coming apart and killing someone bothers you I suggest you practice practicing.  Get some coupons.  Coupons are weldereeze for short pieces of scrap that you can practice on.  Pay attention when you're practicing and then do a destructive test on your weld.  Break it.  Then look where it broke and do your doggonedest to figure out why it broke that way.If you're paying attention as you practice you will remember how it looked, what it sounded like, and how you felt about it when it's a good one.  And when it's a bad one.What will happen over time and lots of practice is your sixth sense will alert you to when things aren't happening just right.  Your sixth sense is that one that puts what the other five have taken in and makes sense of it.  So even as your concentration is on watching the puddle your ears pick up the sound of something going south.  The sixth sense starts tapping on your skull.  And you stop for some reason you can't really explain and you do some checking.  And you shake your head when you find the flaw and wonder how you knew it was there.But your sixth sense only can work when you've practiced, and practiced, and practiced, etc, and so on. Attached Imageslife is good
Reply:I stand corrected.Those aren't cold joints.They're perfectly acceptable welds.The buyer explained to me it was bad paint and had nothing to do with the welds being inferior.  I was the only weldor who thought them bad and they really had to go with the majority opinion on this one.Time will tell who's right.life is good
Reply:yeah that's just rust from under the paint
Reply:The reason I recommend destructive testing immediately after welding when practicing is you can see exactly what happened and it's still fresh in your mind.I'm forever getting asked to repair a broken weld that's prettier than heck.  It looks like a perfect weld.  But when you look at where and how it broke you see it's a cold joint.  A cold joint is where the puddle flowed like caulk but didnt' penetrate one side or the other.A lot of these welds are like those in the pictures, verticals, where the weldor ran down and was concentrating more on staying ahead of the puddle instead of working on welding.When a weld breaks you can look at it and see exactly what happened.  You can see where the weldor had it going right and then he lost concentration and let it get away from him.So don't just practice laying a bead.  Practice laying a bead.  Then break the weld.  Look at where it broke.  Try to figure out why it broke the way it did.  Then work on how you can correct it so that it doesn't happen again.Buy a stick of quarter by two.  Cut it into three inch lengths.  Weld those pieces together in different  positions.  Break them apart right after you weld them together.  Compare what you saw through your lense with what really happened to the metal.life is good
Reply:Harv, I was just wondering because I have to do a dangerous thing and admit to an assumption.  I figured you musta taken them pictures and if you did could you tell me if what im looking at is undercut in well actually all but the one that caught my eye more than any was picture four.  However on second look I swear they all had the undercut.  Its tough from the pictures to know but with as much experience as you have I thought you could be as good a judge of this as anyone from a picture, and especially if you saw them in person.  I have to say Harv that you could be wrong, and I reckon so could I and they could be perfectly good welds, but after looking at them I gotta ask why they the bead looks like such a sharp contrast from the base metal.  Two things I thought of was cold lap, or what my experience says more commonly is the undercut.  I could be wrong but I wanted to ask.CHRIS
Reply:Morning Chris,In person it's obvious they're  cold joints.  You can actually see the fold in of the weld edge.  The rust line just accents it.If I get a chance I'll get out my other camera and try to take a better picture or two.life is good
Reply:Harv,I have studied your web site extensively.    You are about as close to a pro at welding and fabrication as I am ever going to talk to.   I, for one, appreciate your willingness to communicate and teach some of the things you know and have learned in all your years work, and your ability to put it in words that can be understood.  You're a pretty damn fair writer as well as a welder!I am not a welder.  I have a little portable Lincoln SP-170T mig welder and have built a set of gates a couple times and fixed a few things over a few years.   So I can stick metal together, but I'm not a welder yet.    I hope to get closer to the title some day in the future.   The set of gates I just made with my brother for his property were designed after studying your web site.    We made them in the offset vertical style seen on some of your past projects.   They came out pretty decent.So now that I've established my lack of qualifications to judge, I'll go ahead and comment on those car hauler welds anyway.... I think you are right on the money when you called it "caulking."   Cold joints!   They look like decorative frosting on a cake and probably have about the same penetration.    If those joints were on my brother's 55 lb. gates, it would probably be fine.....but on a 2 car hauler going down the highway.....bad news.   This is why I won't weld anything "structural".....something that people's lives can depend on....because I'm not qualified to.   It looks to me like the welder at the trailer manufacturer isn't either.JeffLast edited by rain252; 03-28-2005 at 11:17 AM.
Reply:I agree with Harv.  Those welds look like, either not enough heat, or moving to fast.  I would think that if you consentrate on "Melting" the metal the "Nice looks" come automatically with a good quaility weld.  I like your idea of breaking the welds after practice.  I had a school teacher that use to do that to all my weld jobs.  I learned really quick to make good welds..... It avoided a lot of humiliation from my classmates. When it came time for the drop test. PackratLincoln 225 AC/DC, Hobart 140 Mig. Oxy/propane Victor torch.(2) Makita 5" angle grinders  one with zip disk, 14" chop saw.  and just about every other tool you can think of. Whoever has the most toys when he die's ..... Wins!
Reply:I had to repair a bud's JCB 506C Loadall  Sunday.  I'd used it, actually abused it.  Bent the two and quarter inch cold rolled bar the forks slide back and forth on and busted loose the protection rack at the back of the forks.It was seventy five dollars for the four and a half foot piece of cold rolled. (cold rolled is harder to bend than hot rolled and it's exact in measurement and hot rolled is usually a little over, also cold rolled is more expensive to make and buy)  It was nothing to install, remove two studs, remove old bar, install new bar, replace two studs.Here's a shot of the damaged rack. Attached Imageslife is good
Reply:A close up of where the bar stock ripped out of the weld.  I'm not sure if you can see it clear enough.  But the stock ripped right out of the weld.Double doggone darn, cold joints will find me no matter where and how hard I try to hide!  Attached Imageslife is good
Reply:Harv:  You almost remind me of my buddy.... he use to break things all the time.  But he couldn't weld.  So he'd phone me up and ask me to come fix it for him.  Most of the time I ended up rebuilding the whole thing.  (Front end loaders on farm tractors where not designed to pick up trailers with cars on them).  The weld's held, but the steel just bent, and buckled.  He was really good at testing welds.  If it lasted longer than 30 seconds or 30 feet when Gordon was done with it.  You new the welds were done right.         Worst job I ever did,  was to weld corks on a cat.  Never done it before, and it was -40 that day.  took about 10 hrs, when they loaded the cat onto the flat bed.  All but nine corks fell off.  I was 19 years old and thought I new what I was doing.  Boy was I wrong. Lincoln 225 AC/DC, Hobart 140 Mig. Oxy/propane Victor torch.(2) Makita 5" angle grinders  one with zip disk, 14" chop saw.  and just about every other tool you can think of. Whoever has the most toys when he die's ..... Wins!
Reply:Okay.  I give.  What's a cork?At first I thought it was like the "crack of dawn" of "if I can step across it, I can fill it." One of my bud's says I'm like a bear cub trying to make love to a football.    Of course I do more in a slow day than he can in a fast week.life is good
Reply:A cork is like a lug , welded onto the pad of a Caterpillar track,  Used up here in Canada in the Winter time to keep the machine from sliding sideways on ice.  They are usually about 2" long, and welded alternately on each pad,  two then one, then two.  etc.  all the way around.  The cork material (Mild steel I think) is tapered so that the First pass is done with a 6010, and then two filler passes  with 7018.  -40 temps without ire heat.  I now know why they call them cold welds.....   That was a long time ago, and I can still remember how cold I, was, at the end of the day.  plus how    when they fell off, I have not ever tried to weld them on again.  If I knew then what I know now..... things might be different.  Packrat.Lincoln 225 AC/DC, Hobart 140 Mig. Oxy/propane Victor torch.(2) Makita 5" angle grinders  one with zip disk, 14" chop saw.  and just about every other tool you can think of. Whoever has the most toys when he die's ..... Wins!
Reply:Im from Dallas but recently moved to B.C. and although this winter I did not have to do any actual preheating we did have to use a big diesel heater to warm the shop up a lil before we welded.  The owner said it gets a lot colder, and sometiems they need a rosebud, but it was cold enough that with this heater we couold warm the shop up and all was good.  Sure was a big adjustment coming from a mild winter place like Dallas where I never once had to preheat anything that ordinarily dont need it.  Id say its a cool learning experience but I cant wait to get back home!
Reply:You are from a great state like Texas and you moved to.....CANADA?????     Well at least you moved to western Canada, and not eastern, where all those American-hating french canadians are.      Yes.....piss on you America haters in Canada.   If your country had come up beside a country like the USSR......how long ago do you think you'd have become a satellite of the USSR?    Don't doubt that for a minute.   You have lived in peace and prosperity next to the most powerful country in the world who could have squashed you like a bug and you've never had to fear aggression.  Yet huge #'s (a majority?) of eastern canadians are America haters.    I say....piss off to those canadians.  (of course the canadians that have some sense and don't feel that way, this is not directed at you.)
Reply:maybe moving up north wasn't his idea or in his controlStangnetShop Full Of Stuff. Joey
Reply:I'm just pulling his leg about moving up there.   we all do what we have to do to live.       but that IS how I feel about the canadians that have the America- hating disease.
Reply:HAHA  Well I wasnt too found of moving here myself, but its not bad.  Most people here are rather friendly.  They get mad and blame americans for american politics.  When you explain the feelings of most,  at least most I know (americans) the canadians are like well well, really?   Them americans aint so bad after all.  Then they tel you its there politicians that pull all this stupid **** too and its jsut a big mess.  Most that ive known are like look if theres something worth fighting for lets team up,  whoop *** and get back to our lives.  There of course are always some cowardly double talking types, but you find that in every group of people I think.Y'all have a good one now
Reply:Hmmm,  where to start.  Not all French Canadians hate Americans, heck many of them like the US more than they do the rest of Canada.    Many Canadians get the wrong impression of the American people cause of what we see on tv,  just like many of you have certain notions of what we stand for based on (usually) limited information. Governments are one thing, but regular Joe Canuck and regular Joe American are pretty much the same.  But of course, we have better beer.  And TX, if you were cold in BC, come out east next winter.
Reply:Tx:  What part of BC are you in?  It doesn't usually get very cold in the southern part, and on the coast.  But if your further north or inland, up in the mountains.  Well ya maybe.  But like reaper said, try the east.   Alberta wasn't to bad this year.  Only got down to -38 Celsius for a couple of day's this winter. But we did get lots of the white stuff.  All the more fun for snowmobiles, and playing with the snow plow I built.      Up here in Canada, we don't call ourselves rednecks.  In Alberta we're just Bush Hippies.    Lincoln 225 AC/DC, Hobart 140 Mig. Oxy/propane Victor torch.(2) Makita 5" angle grinders  one with zip disk, 14" chop saw.  and just about every other tool you can think of. Whoever has the most toys when he die's ..... Wins!
Reply:I know....there are good, and worthless types, no matter where you go....including here in the USA.   I'll get off the soap box.
Reply:okanaganTX: The tropics!Rain: couldn't agree with you more. Humans are Humans, and for the most part, we all just want to live our lives as best we can.  There's bad apples everywhere,  but they don't represent where they're from.  Packrat: I envy you.  I don't think we got lower than -25 this winter, and had far less snow than usual.  Never had to plug the truck in.  One of those winters where its just sort of cold, but not really.  Give me summer or give me winter dammit. This inbetween stuff is worse than -40.
Reply:Our winter was a littel weird this year too.  We got the kind of weather they get in Ontario, and Quebec this year.  Feb. brought us a freezing rain storm.  We had more big trucks in the ditch this year than I've ever seen.  It just poured rain and the highways had about 1" of ice on them.  The trucks were all driving around with they're chains on.  Yup... even on the pavement.       I got my tractor stuck about 4 times just trying to plow the driveway out.  All that ice under the snow didn't do us any good, traction wise, even with chains on the old girl.  But my chains are pretty wore down,  I plan to change the cross links out this summer.  New links with ice lugs on them.  Try and stop that old tractor next winter  ha ha.    Lincoln 225 AC/DC, Hobart 140 Mig. Oxy/propane Victor torch.(2) Makita 5" angle grinders  one with zip disk, 14" chop saw.  and just about every other tool you can think of. Whoever has the most toys when he die's ..... Wins!
Reply:Those drivers would have been in a world of umm "crap" if they'd been on Quebec roads with chains.  Thank God we had no major freezing rain this year.  You would have heard about it like '98 though.  All I can say now is that spring is here, camping starts soon, and life is good.  Cheers!