Problem with mig welding heavy equipment

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Had to repair bad mig weld on a brush mower.




Reply:The cleanups



Reply:The welding


Reply:The welding


Reply:Wow....those pealed back like a grape!  I'm often amazed at how light many quick attach plates are...way lighter material than I would use if I was making one.Check out my bench vise website:  http://mivise.comMiller Syncrowave 250DXMillermatic 350P with XR AlumaProMiller Regency 200 with 22A feeder and Spoolmatic 3Hobart Champion EliteEverlast PowerTig 210EXT
Reply:Nice repair. Pretty sad seeing factory welds that bad. I had the samething on a rear backblade. Cold MIG weld and no penetration. Weld stuck to oneside. Sent from my iPhone using Tapatalk
Reply:5/16 steel plate . Silicon caulk probably would’ve stuck better


Reply:I had a similar repair on a loader mounted to a Deutz. The loader mounting brackets peeled back at the weld, evident lack of penetration. After prep we opt to stick, thats been about 6 years ago and it is still holding. I had a couple of pics but cant find them.  My guess is your back in business better than new. Thanks for posting.GeezerPower Mig 255C185 TIGBlue 175 MIGRanger 8 Kohler 20HP1974 5K Lincoln/Wisconsin Powered (Cherry)Victor/Harris O/AK 487 Spool Gun
Reply:I weld most shop things with mig but if it absolutely can't leak the first time, or is going to take a beating with minimal area to add material out comes the stick. i think it has more to do with the way I learned rather than ones better or worse than the other.  for me I just have better control of the puddle. the young man working for me absolutely the opposite does an incredible job but he knows how to set up the mig. which is a science on its ownDo not argue with an idiot. He will drag you down to his level and beat you with experience.
Reply:Looks great and big profits too.There is no JB Weld to clean off I like charger for that too.Remember when looking at the job, do not smile bite your tongue it helps sales.It looks like solid wire low cost manufacturers love the solid  wire. But repair industry enjoy the extra work.That is why in my shop we never used solid wireDave

Originally Posted by Bls repair

Had to repair bad mig weld on a brush mower.




Reply:I don't think the problem is the MIG welding itself, but the wrong welding parameters. If that weld had been made in Spray transfer, I think it would be fine. Even with thick enough wire and shortcircuit (hot) it could work.The problem with MIG is that you can make a pretty bead with ZERO penetration. But that's not the MIG's fault!Great save by the way!Mikel
Reply:

Originally Posted by Mikel_24

I don't think the problem is the MIG welding itself, but the wrong welding parameters. If that weld had been made in Spray transfer, I think it would be fine. Even with thick enough wire and shortcircuit (hot) it could work.The problem with MIG is that you can make a pretty bead with ZERO penetration. But that's not the MIG's fault!Great save by the way!Mikel
Reply:On long runs of disimilar thickness or heat sinked metal what happens is the difference in expansion and shrinkage between the two pieces of metal is different. I saw what could only be considered a perfect weld on an aluminum davot for a boat, do that upon cooling, it was loud and pretty unbelievable. But one piece was cooling off much faster than the other and caused the weld to just tear and pop the whole way down. If you can preheat and let her cool down slowly it seems ok and holds. My thoughts where what about on a really cold day, what might happen. Sincerely, William McCormickIf I wasn't so.....crazy, I wouldn't try to act normal, and you would be afraid.
Reply:I'm not disputing your example William, but in this case if it was down to weld restraint and expansion/contraction, then it would have failed either in the centre of the weld if the weld had lower yield than parent, or in the heat affected zone. You'd get a pronounced longitudinal crack with slight steps in it where the metal has microcracked at different intervals.You can clearly see in the above pictures that the failure is in straight lines right along the weld bead edges, and left a clean line on the parent material. So this occured due to lack of fusion, both to parent material, and also between runs. Lack of fusion with MIG is generally down to settings, or if the amps are marginal, then poor technique. But for mass production, it's a set up problem.
Reply:

[/QUOTE]The end plates are the most important part of these type of brackets, just look at the photo.

***********************CR
Reply:There is nothing at all wrong with mig hard wire.  The above is a perfect example of cold lap and is caused by poor setup by the person doing the welding.  If you know how to read a weld puddle this problem is very easy to see. The problem is many mig operators do not know what they are seeing. Cold lap is very hard to find after the fact and is why it is so dangerous. As far as spray transfer , it is only for flat position and if the part is on a jig and can be quickly rotated it would be good but in the real world spray mode is not really the answer for production welding parts as shown.  This is 100% weld operator failure.  IMHO all the welds on this part should be redone , it is the only way to be sure the next weakest weld will not fail.
Reply:It is a operator error But the problem is a cold Mig weld looks good.If you are doing cold weld you may need to redo at your cost.Now if you weld shop having to redo a manufacturer's cold weld it great for your profits.Let's hope it not on building you own.Dave

Originally Posted by thegary

There is nothing at all wrong with mig hard wire.  The above is a perfect example of cold lap and is caused by poor setup by the person doing the welding.  If you know how to read a weld puddle this problem is very easy to see. The problem is many mig operators do not know what they are seeing. Cold lap is very hard to find after the fact and is why it is so dangerous. As far as spray transfer , it is only for flat position and if the part is on a jig and can be quickly rotated it would be good but in the real world spray mode is not really the answer for production welding parts as shown.  This is 100% weld operator failure.  IMHO all the welds on this part should be redone , it is the only way to be sure the next weakest weld will not fail.
Reply:There is a 5/16 plate between the two welds


Reply:from what i'm seeing with my old eyes is the mounting bracket for the hog is carrying all of the weight of attachment.  That weight is amplified at the mount by the attachment hanging out front.  I also got a few bucks that says the operator was running top speed over some awesome terrain.  The goober shows no fusion at all and is most likely the primary point of failure.  the weld was just sittin there lookin purty.
Reply:Exactly,now we’ll see what goes next .  My money is on bucket cylinders.  I suggested running some support from front to boom arms for road travel


Reply:Looks great It bring more great work Dave

Originally Posted by Bls repair

Exactly,now we’ll see what goes next .  My money is on bucket cylinders.  I suggested running some support from front to boom arms for road travel


Reply:

Originally Posted by Munkul

I'm not disputing your example William, but in this case if it was down to weld restraint and expansion/contraction, then it would have failed either in the centre of the weld if the weld had lower yield than parent, or in the heat affected zone. You'd get a pronounced longitudinal crack with slight steps in it where the metal has microcracked at different intervals.You can clearly see in the above pictures that the failure is in straight lines right along the weld bead edges, and left a clean line on the parent material. So this occured due to lack of fusion, both to parent material, and also between runs. Lack of fusion with MIG is generally down to settings, or if the amps are marginal, then poor technique. But for mass production, it's a set up problem.
Reply:Dayum, that weld looks awful pretty just settin there doin nothin. It looks like it might be a robot weld? I dont have much experience in manufacturing stuff like this but I have fixed a lot of stuff like this over the years and most of it looks just like this, beautiful weld like a robot done it and it falls apart with no penetration at all.  To repair it I do just what you done here and use stick or a wire feeder with self shielded flux core. Another good job done by someone knows what the score is
Reply:Thanks
Reply:

Originally Posted by William McCormick

I see that cold start with MIG and Stick all the time. But who is going to do a run in tab today? I used to MIG weld large buckets and the only way to do it was to preheat them. When you got done the whole area was glowing red hot. Anything less and it was a crack waiting to happen. I found that if you go through the trouble to MIG correctly on critical things you may as well set up automated TIG with a camera.Sincerely, William McCormick

Originally Posted by Bls repair

Thanks
Reply:Tsk Tsk, Spammers sure are trying to be clever nowadays.Last edited by HTalk Dad; 16 Hours Ago at 11:45 AM.Lincoln 330 MPXModified TombstoneLincoln LN-25X-TVTMagnum PRO 250LX GT Spool Gun¼ Ton of Torches OFC-A / OFG-ASMAW FCAW GMAW Air Carbon Arc Gouging#Freebird Welds
Reply:This is a design problem as much as welding, in some sense I agree with William here.  They simply dumped a filler plate in and welded it along. Wasnt built right to start with.  Irs simply a couple stringers next to each other  in a big long joint under stress.    We use mostly hard wire short circuit but its limited thickness and when it gets heavier make sure its melted and hot doing it.   Someone else eluded to the operators not seeing it, I agree.  Was in welding school with a guy was there for 2 years and still couldnt see a rolled bead was obvious and couldnt melt warm butter.  I bet this isnt the only one,,, or maybe it was a boogered build repair with the filler,,,, cant tell if it needs to be there or what etc.    I am not in a big hurry to totally blame the weldor here, guys dont often have a choice in those positions.   I also know a meturlurgical engineer who has never struck an arc or lit a torch, kind of pathetic.  I am sure there are areas of expertise he does know but has trouble with a screwdriver.  Worked in a foundry for decades. Some place they made brake rotors.Last edited by Sberry; 15 Hours Ago at 11:58 AM.www.urkafarms.com
Reply:The only thing good about mig welding is that you can make a crappy weld faster than you can with other processes.  Just kidding... sort of... I've tried to like mig, but have seen plenty of failures just like this. Really easy to make a bad weld that looks good.